Transcriber’s Note


Superscripts are preceded by a ^ or enclosed in ^{braces}; italics are
enclosed in _underscores_; boldface is enclosed in =equals signs=.




  _THE CENTURY SCIENCE SERIES_

  EDITED BY SIR HENRY E. ROSCOE, D.C.L., LL.D., F.R.S.


  MICHAEL FARADAY

  HIS LIFE AND WORK




The Century Science Series.

_Edited by_ SIR HENRY ROSCOE, D.C.L., F.R.S.

3s. 6d. _each_.


  Pasteur.

    By PERCY FRANKLAND, Ph.D.(Würzburg), B.Sc. (Lond.), F.R.S., and
    Mrs. PERCY FRANKLAND.


Humphry Davy, Poet and Philosopher.

    By T. E. THORPE, LL.D., F.R.S.


Charles Darwin and the Theory of Natural Selection.

    By EDWARD B. POULTON, M.A., F.R.S.


John Dalton and the Rise of Modern Chemistry.

    By Sir HENRY E. ROSCOE, F.R.S.


Major Rennell, F.R.S., and the Rise of English Geography.

    By Sir CLEMENTS R. MARKHAM, C.B., F.R.S.


Justus von Liebig: his Life and Work (1803–1873).

    By W. A. SHENSTONE, F.I.C., Lecturer on Chemistry in Clifton
    College.


The Herschels and Modern Astronomy.

    By AGNES M. CLERKE.


Charles Lyell and Modern Geology.

    By Professor T. G. BONNEY, F.R.S.


J. Clerk Maxwell and Modern Physics.

    By R. T. GLAZEBROOK, F.R.S.

       *       *       *       *       *


Michael Faraday: his Life and Work.

    By Prof. SILVANUS P. THOMPSON, F.R.S. 5s.




CASSELL & COMPANY, LIMITED, _London; Paris, New York & Melbourne_.




[Illustration: Ever Yours Truly

M Faraday]




  _THE CENTURY SCIENCE SERIES_


  MICHAEL FARADAY

  HIS LIFE AND WORK


  BY
  SILVANUS P. THOMPSON, D.Sc., F.R.S.

  PRINCIPAL OF AND PROFESSOR OF PHYSICS IN THE CITY AND GUILDS
  OF LONDON TECHNICAL COLLEGE, FINSBURY


  CASSELL AND COMPANY, LIMITED
  _LONDON, PARIS, NEW YORK & MELBOURNE_
  1898

  [ALL RIGHTS RESERVED]

[Illustration]


ON A PORTRAIT OF FARADAY.

  Was ever man so simple and so sage,
      So crowned and yet so careless of a prize!
      Great Faraday, who made the world so wise,
  And loved the labour better than the wage.

  And this you say is how he looked in age,
      With that strong brow and these great humble eyes
      That seem to look with reverent surprise
  On all outside himself. Turn o’er the page,

  Recording Angel, it is white as snow.
      Ah God, a fitting messenger was he
  To show Thy mysteries to us below.
      Child as he came has he returned to Thee.
  Would he could come but once again to show
      The wonder-deep of his simplicity.

                                        COSMO MONKHOUSE.




PREFACE


Shortly after the death of Faraday in 1867, three biographies of
him--each admirable in its own line--were published. The “Life and
Letters of Faraday,” by Dr. Bence Jones, secretary of the Royal
Institution, which was issued in 1868 in two volumes, has long been
out of print. “Faraday as a Discoverer,” written in 1868 by Professor
Tyndall, which, though slighter as a record, brings out many points of
character into striking relief, is also now exhausted. Dr. Gladstone’s
“Michael Faraday,” published in 1872, so rich in reminiscences, and
so appreciative of the moral and religious side of his character, is
also out of print. Other and briefer biographies exist; the “Éloge
Historique” of M. Dumas; the article “Faraday” in the “Encyclopædia
Britannica” by Professor Clerk Maxwell; and the chapter on Faraday
in Dr. W. Garnett’s “Heroes of Science.” But there seems room for
another account of the life and labours of the man whose influence
upon the century in which he lived was so great. For forty years he
was a living and inspiring voice in the Royal Institution, beyond all
question the greatest scientific expositor of his time. Throughout
almost the whole of that time his original researches in physics, and
chiefly in electricity, were extending the boundaries of knowledge
and laying the foundations not only for the great developments of
electrical engineering of the last twenty years but for those still
greater developments in the theories of electricity, magnetism, and
light which are every year being extended and made fruitful. Were there
no other reason than these developments in practice and theory, they
would amply justify the effort to review now, after so many years, the
position of Faraday amongst the eminent men of the century now drawing
to its close.

Those who were intimately acquainted with him are a fast dwindling
band. In the recollection of such as have survived him, his image lives
and moves, surrounded with gracious memories, a vivid personality
instinct with rare and unselfish kindliness. But the survivors are few,
and their ranks grow thinner with each succeeding year. And so it comes
about that the task of writing of his life and work has been entrusted
to one who never ceases to regret that he never met Faraday.

Thanks to the permission of the managers of the Royal Institution,
a number of short extracts from Faraday’s notebooks, hitherto
unpublished, are now printed for the first time. Much more remains
which it is to be hoped, for the benefit of science, may be published
ere long. The author desires further to acknowledge the kindness
of Messrs. Longmans & Co. in allowing the reproduction of the
illustrations on pages 3 and 258, which are taken from Bence Jones’s
“Life and Letters of Faraday,” published in 1868. Mr. Elkin Mathews has
kindly permitted the insertion of the sonnet by Mr. Cosmo Monkhouse
which follows the title-page. The author is also indebted to Dr. J.
Hall Gladstone, F.R.S., for many valuable notes and suggestions, and to
Miss M. K. Reynolds for photographs used in preparing Fig. 14. Most of
all he is indebted to Miss Jane Barnard for access to Faraday’s private
papers, and for permission to print certain extracts from them.

                                        S. P. T.




CONTENTS


                                                                   PAGE
  CHAP. I.--EARLY LIFE, TRAINING, AND TRAVEL                          1

  CHAP. II.--LIFE AT THE ROYAL INSTITUTION                           35

  CHAP. III.--SCIENTIFIC RESEARCHES--FIRST PERIOD                    75

  CHAP. IV.--SCIENTIFIC RESEARCHES--SECOND PERIOD                   102

  CHAP. V.--SCIENTIFIC RESEARCHES--THIRD PERIOD                     172

  CHAP. VI.--MIDDLE AND LATER LIFE                                  222

  CHAP. VII.--VIEWS ON THE PURSUIT OF SCIENCE AND ON EDUCATION      261

  CHAP. VIII.--RELIGIOUS VIEWS                                      286




LIST OF ILLUSTRATIONS


  Portrait                                               _Frontispiece_

  FIGS.                                                            PAGE
   1. Riebau’s Shop                                                   3
   2. Electromagnetic Rotations (facsimile sketch)                   88
   3. Apparatus for Rotation (facsimile sketch)                      88
   4. Faraday’s Ring (facsimile sketch)                             108
   5. Induction Experiment (facsimile sketch)                       111
   6. The “New Electrical Machine” (facsimile sketch)               121
   7. The Teetotum Apparatus                                        123
   8. The Revolving Copper Cylinder (facsimile sketch)              124
   9. Earth Inductor                                                125
  10. A Spark from a Magnet (facsimile sketch)                      129
  11. How to Cut the Magnetic Lines                                 133
  12. Illustration of the New Terms (facsimile sketch)              145
  13. Bundle of Wires (facsimile sketch)                            151
  14. Apparatus for Investigating Dielectric Capacity               159
  15. Block of Heavy-glass (facsimile sketch)                       176
  16. Action of Magnet on Light (facsimile sketch)                  177
  17. Arrangements of Magnets (facsimile sketch)                    178
  18. The Ring Electromagnet (facsimile sketch)                     179
  19. The Equatorial Position                                       188
  20. Illustration of Lateral Vibrations                            195
  21. A Lecture Model                                               239
  22. Cottage at Hampton Court                                      258




MICHAEL FARADAY.




CHAPTER I.

EARLY LIFE, TRAINING, AND TRAVEL.


On the 22nd of September, 1791, was born, at Newington Butts, then an
outlying Surrey village, but since long surrounded and swallowed up
within the area of Greater London, the boy Michael Faraday. He was
the third child of his parents, James and Margaret Faraday, who had
but recently migrated to London from the little Yorkshire village of
Clapham. Clapham lies under the shadow of Ingleborough, on the western
border of the county, midway between Settle and Kirkby Lonsdale.
The father, James Faraday, was a working blacksmith; the mother,
daughter of a farmer of Mallerstang, the romantic valley which runs
past Pendragon Castle to Kirkby Stephen. James Faraday was one of the
ten children of a Robert Faraday, who in 1756 had married Elizabeth
Dean, the owner of a small homestead known as Clapham Wood Hall, since
pulled down. All Robert Faraday’s sons appear to have been brought up
to trades, one being a shoemaker, another a grocer, another a farmer,
another a flax-worker, and another a shopkeeper. Descendants of some of
these still live in the district.

After Michael’s birth, his parents moved to the north side of the
Thames, living for a short time in Gilbert Street, but removing in
1796 to rooms over a coach-house in Jacob’s Well Mews, Charles Street,
Manchester Square, where they lived till 1809. In that year, young
Michael being now nearly eighteen years old, they moved to 18, Weymouth
Street, Portland Place. Here in the succeeding year James Faraday, who
had long been an invalid, died; his widow, who for some years remained
on at Weymouth Street, maintaining herself by taking in lodgers until
her sons could support themselves and her, survived till 1838. Though
a capable woman and a good mother, she was quite uneducated. In her
declining years she was wholly supported by her son, of whom she was
very proud, and to whom she was devoted.

Michael received very little schooling. One of his nephews tells
the following tale of his boyhood. He was at a dame’s school; and,
either from some defect in his speech or because he was too young
to articulate his _r_’s properly, he pronounced his elder brother’s
name “Wobert.” The harsh schoolmistress, bent on curing the defect by
personal chastisement, sent the aforesaid “Wobert” out with a halfpenny
to get a cane, that young Michael might be duly flogged. But this
refinement of cruelty reacted on itself; for Robert, boiling with
indignation, pitched the halfpenny over a wall, and went home to tell
his mother, who promptly came down to the scene of action and removed
both boys from the school. From the age of five to thirteen Michael
lived at Jacob’s Well Mews, spending his out-of-school hours at home or
in the streets playing at marbles and other games with the children of
the neighbourhood.

[Illustration: RIEBAU’S SHOP.]

[Sidenote: BOOKBINDER’S ERRAND-BOY.]

In 1804 he went on trial for twelve months as errand-boy to a
bookseller and stationer at No. 2, Blandford Street--Mr. George Riebau.
This house, which is still kept as a stationer’s shop (by Mr. William
Pike), is now marked with an enamelled tablet recording its connection
with the life of Faraday.[1] When he first went to Mr. Riebau, it was
his duty to carry round the newspapers in the morning. He has been
graphically described as a bright-eyed errand-boy who “slid along the
London pavements, with a load of brown curls upon his head and a packet
of newspapers under his arm.” Some of the journals were lent out, and
had to be called for again. He was very particular on Sunday mornings
to take them round early, that he might complete his work in time to
go with his parents to their place of worship. They belonged--as his
grandfather before him--to the sect known as Sandemanians, a small
body which separated from the Presbyterian Church of Scotland towards
the middle of the eighteenth century. Their views, which were very
primitive, were held with intense earnestness and sincerity of purpose.
Their founder had taught that Christianity never was or could be the
formal or established religion of any nation without subverting its
essential principles; that religion was the affair of the individual
soul; and that “the Bible” alone, with nothing added to it or taken
away from it by man, was the sole and sufficient guide for the soul.
They rejected all priests or paid ministers, but recognised an
institution of unpaid eldership. Their worship was exceedingly simple.
Though their numbers were few, they were exceedingly devout, simple,
and exclusive in their faith. Doubtless the rigorous moral influences
pervading the family and friends of James Faraday had a great part in
moulding the character of young Michael. To his dying day he remained a
member of this obscure sect. As he was no merely nominal adherent, but
an exceedingly devoted member, and at two different periods of his life
an elder and a preacher, no review of his life-work would be complete
without a fuller reference to the religious side of his character.

[Sidenote: APPRENTICED AS BOOKBINDER.]

After the year of trial, Michael Faraday was formally apprenticed to
learn the arts of bookbinder, stationer, “and bookseller,” to Mr.
Riebau. The indenture[2] is dated October 7, 1805. It is stated that,
“in consideration of his faithful service, no premium is given.” During
his seven years of apprenticeship there came unexpected opportunities
for self-improvement. Faraday’s lifelong friend and co-religionist,
Cornelius Varley, says:--“When my attention was first drawn to Faraday,
I was told that he had been apprenticed to a bookbinder. I said he
was the best bookworm for eating his way to the inside; for hundreds
had worked at books only as so much printed paper. Faraday saw a mine
of knowledge, and resolved to explore it.” To one of his friends he
said that a book by Watts, “On the Mind,” first made him think, and
that the article on “Electricity” in a cyclopædia which came into his
hands to be bound first turned his attention to science. He himself
wrote:--“Whilst an apprentice I loved to read the scientific books
which were under my hand; and, amongst them, delighted in Marcet’s
‘Conversations in Chemistry’ and the electrical treatises in the
‘Encyclopædia Britannica.’ I made such simple experiments in chemistry
as could be defrayed in their expense by a few pence per week, and
also constructed an electrical machine, first with a glass phial, and
afterwards with a real cylinder, as well as other electrical apparatus
of a corresponding kind.” This early machine[3] is now preserved at
the Royal Institution, to which it was presented by Sir James South.
Amongst the books which he had to bind were Lyons’ “Experiments on
Electricity” and Boyle’s “Notes about the Producibleness of Chymicall
Principles,” which books, together with Miss Burney’s “Evelina,” all
bound with his own hands, are still preserved in the Royal Institution.

[Sidenote: NEW ACQUAINTANCES.]

Walking near Fleet Street, he saw displayed a bill announcing that
evening lectures on natural philosophy were delivered by Mr. Tatum
at 53, Dorset Street, Salisbury Square, E.C., price of admission one
shilling. With his master’s permission, and money furnished by his
elder brother Robert, who was a blacksmith and (later) a gasfitter,
Michael began to taste scientific teaching. Between February, 1810,
and September, 1811, he attended some twelve or thirteen lectures. He
made full and beautiful notes of all he heard: his notebooks, bound
by himself, being still preserved. At these lectures he fell in with
several thoroughly congenial comrades, one of them, by name Benjamin
Abbott, being a well-educated young Quaker, who was confidential
clerk in a mercantile house in the City. Of the others--amongst
whom were Magrath, Newton, Nicol, Huxtable, and Richard Phillips
(afterwards F.R.S. and President of the Chemical Society)--several
remained lifelong friends. Happily for posterity, the letters--long
and chatty--which the lad wrote in the fulness of his heart to Abbott
have been preserved; they are published in Bence Jones’s “Life and
Letters.” They are remarkable not only for their vivacity and freshness
but for their elevated tone and excellent composition--true specimens
of the lost art of letter-writing. The most wonderful thing about them
is that they should have been written by a bookbinder’s apprentice of
no education beyond the common school of the district. In his very
first letter he complains that ideas and notions which spring up in his
mind “are irrevocably lost for want of noting at the time.” This seems
the first premonition of that loss of memory which so afflicted him
in after life. In his later years he always carried in his waistcoat
pocket a card on which to jot down notes and memoranda. He would
stop to set down his notes in the street, in the theatre, or in the
laboratory.

Riebau, his master in the bookbinding business, seems, from the way
he encouraged the studies of his young apprentice, to have been no
ordinary man. His name would suggest a foreign extraction; and to his
shop resorted more than one political refugee. There lodged at one time
at Riebau’s an artist named Masquerier,[4] who had painted Napoleon’s
portrait and had fled from France during the troublous times. For
the apprentice boy, who used to dust his room and black his boots,
Masquerier took a strong liking. He lent him books on perspective
and taught him how to draw. Another frequenter of Riebau’s shop was
a Mr. Dance, whose interest in the industry and intelligence of the
apprentice led him to an act which changed the whole destiny of his
life. Faraday himself, in the very few autobiographical notes which he
penned, wrote thus:--

    During my apprenticeship I had the good fortune, through the
    kindness of Mr. Dance, who was a customer of my master’s shop
    and also a member of the Royal Institution, to hear four of the
    last lectures of Sir H. Davy in that locality.[5] The dates
    of these lectures were February 29, March 14, April 8 and 10,
    1812. Of these I made notes, and then wrote out the lectures in
    a fuller form, interspersing them with such drawings as I could
    make. The desire to be engaged in scientific occupation, even
    though of the lowest kind, induced me, whilst an apprentice,
    to write, in my ignorance of the world and simplicity of my
    mind, to Sir Joseph Banks, then President of the Royal Society.
    Naturally enough, “No answer” was the reply left with the
    porter.

[Sidenote: LETTERS TO ABBOTT.]

He submitted his notes to the criticism of his friend Abbott, with whom
he discussed chemical and electrical problems, and the experiments
which they had individually tried. Out of this correspondence, one
letter only can be given; it was written September 28, 1812, ten days
before the expiry of his apprenticeship:--

    Dear A----, ... I will hurry on to philosophy, where I am a
    little more sure of my ground. Your card was to me a very
    interesting and pleasing object. I was highly gratified in
    observing so plainly delineated the course of the electric
    fluid or fluids (I do not know which). It appears to me that by
    making use of a card thus prepared, you have hit upon a happy
    illustrating medium between a conductor and a non-conductor;
    had the interposed medium been a conductor, the electricity
    would have passed in connection through it--it would not have
    been divided; had the medium been a non-conductor, it would
    have passed in connection, and undivided, as a spark over
    it, but by this varying and disjoined conductor it has been
    divided most effectually. Should you pursue this point at
    any time still further, it will be necessary to ascertain by
    what particular power or effort the spark is divided, whether
    by its affinity to the conductor or by its own repulsion; or
    if, as I have no doubt is the case, by the joint action of
    these two forces, it would be well to observe and ascertain
    the proportion of each in the effect. There are problems,
    the solution of which will be difficult to obtain, but the
    science of electricity will not be complete without them;
    and a philosopher will aim at perfection, though he may not
    hit it--difficulties will not retard him, but only cause a
    proportionate exertion of his mental faculties.

    I had a very pleasing view of the planet Saturn last week
    through a refractor with a power of ninety. I saw his ring
    very distinctly; ’tis a singular appendage to a planet, to
    a revolving globe, and I should think caused some peculiar
    phenomena to the planet within it. I allude to their mutual
    action with respect to meteorology and perhaps electricity....

The master, a French emigré named De la Roche, of King Street, Portman
Square, to whom he engaged himself as a journeyman bookbinder, was of
a very passionate disposition, and made Faraday very uncomfortable. He
longed to get out of trade, and under the encouragement of Mr. Dance
he wrote to Sir Humphry Davy, sending, “as a proof of my earnestness,”
the notes he had taken of Davy’s last four lectures. Faraday’s letter,
which has been preserved but never published, is an astounding example
of the high-flown cringing style in vogue at that date. Davy’s reply
was favourable, and led to a temporary engagement of some days as
amanuensis at the time when he was wounded in the eye by an explosion
of the chloride of nitrogen. Faraday himself, nearly twenty years
afterwards, wrote[6] a full account of the circumstances.

    [_M. Faraday to Dr. J. A. Paris._]

                              Royal Institution, December 23, 1829.

    MY DEAR SIR,--You asked me to give you an account of my first
    introduction to Sir H. Davy, which I am very happy to do, as I
    think the circumstances will bear testimony to his goodness of
    heart.

    When I was a bookseller’s apprentice, I was very fond of
    experiment and very adverse to trade. It happened that a
    gentleman, a member of the Royal Institution, took me to hear
    some of Sir H. Davy’s last lectures in Albemarle Street. I took
    notes, and afterwards wrote them out more fairly in a quarto
    volume.

    My desire to escape from trade, which I thought vicious and
    selfish, and to enter into the service of Science, which I
    imagined made its pursuers amiable and liberal, induced me at
    last to take the bold and simple step of writing to Sir H.
    Davy, expressing my wishes, and a hope that, if an opportunity
    came in his way, he would favour my views; at the same time, I
    sent the notes I had taken of his lectures.

    The answer, which makes all the point of my communication, I
    send you in the original, requesting you to take great care of
    it, and to let me have it back, for you may imagine how much I
    value it.

    You will observe that this took place at the end of the year
    1812, and early in 1813 he requested to see me, and told me
    of the situation of assistant in the laboratory of the Royal
    Institution, then just vacant.

    At the same time that he thus gratified my desires as to
    scientific employment, he still advised me not to give up the
    prospects I had before me, telling me that Science was a harsh
    mistress; and in a pecuniary point of view but poorly rewarding
    those who devoted themselves to her service. He smiled at my
    notion of the superior moral feelings of philosophic men, and
    said he would leave me to the experience of a few years to set
    me right on that matter.

    Finally, through his good efforts I went to the Royal
    Institution early in March of 1813, as assistant in the
    laboratory; and in October of the same year went with him
    abroad as his assistant in experiments and in writing. I
    returned with him in April, 1815, resumed my station in the
    Royal Institution, and have, as you know, ever since remained
    there.

                              I am, dear Sir, very truly yours,
                                                      M. FARADAY.


[Sidenote: WINS FAVOUR WITH DAVY.]

The following is Davy’s note:--

    _Mr. P. Faraday, 188, Weymouth St., Portland Place._

                                        December 24, 1812.

    SIR,--I am far from displeased with the proof you have given
    me of your confidence, and which displays great zeal, power
    of memory, and attention. I am obliged to go out of Town, and
    shall not be settled in town till the end of Jan^y I will then
    see you at any time you wish. It would gratify me to be of any
    service to you; I wish it may be in my power.

                                              I am Sir
                                        your obt. humble servt.
                                                  H. DAVY.


Accordingly, Faraday called on Davy, who received him in the anteroom
to the lecture theatre, by the window nearest to the corridor. He
advised him then to stick to bookbinding, promising to send him books
from the Institution to bind, as well as other books. He must have been
agreeably impressed, otherwise he would not, when disabled, have sent
for Faraday to write for him. Early in 1813 the humble household, in
which Faraday lived with his widowed mother in Weymouth Street, was one
night startled by the apparition of Sir Humphry Davy’s grand coach,
from which a footman alighted and knocked loudly at the door. For young
Faraday, who was at that moment undressing upstairs, he left a note
from Sir Humphry Davy requesting him to call next morning. At that
interview Davy asked him whether he was still desirous of changing his
occupation, and offered him the post of assistant in the laboratory in
place of one who had been dismissed. The salary was to be twenty-five
shillings a week, with two rooms at the top of the house. The minute
appointing him is dated March 1, 1813:--

[Sidenote: ENTERS ROYAL INSTITUTION.]

    Sir Humphry Davy has the honour to inform the managers that
    he has found a person who is desirous to occupy the situation
    in the Institution lately filled by William Payne. His name
    is Michael Faraday. He is a youth of twenty-two years of age.
    As far as Sir H. Davy has been able to observe or ascertain,
    he appears well fitted for the situation. His habits seem
    good, his disposition active and cheerful, and his manner
    intelligent. He is willing to engage himself on the same
    terms as those given to Mr. Payne at the time of quitting the
    Institution.

    Resolved--That Michael Faraday be engaged to fill the situation
    lately occupied by Mr. Payne on the same terms.[7]

There have come down several additions to the story. One, probably
apocryphal, says that Faraday’s first introduction to Davy was
occasioned by Davy’s calling at Riebau’s to select some bookbinding,
and seeing on the shelves the bound volume of manuscript notes of
his own lectures. The other was narrated by Gassiot to Tyndall, as
follows:--

                                        Clapham Common, Surrey,
                                                November 28, 1867.

    MY DEAR TYNDALL,--Sir H. Davy was accustomed to call on the
    late Mr. Pepys in the Poultry, on his way to the London
    Institution, of which Pepys was one of the original managers;
    the latter told me that on one occasion Sir H. Davy, showing
    him a letter, said, “Pepys, what am I to do?--here is a letter
    from a young man named Faraday; he has been attending my
    lectures, and wants me to give him employment at the Royal
    Institution--what can I do?” “Do?” replied Pepys, “put him
    to wash bottles; if he is good for anything he will do it
    directly; if he refuses, he is good for nothing.” “No, no,”
    replied Davy, “we must try him with something better than
    that.” The result was, that Davy engaged him to assist in the
    Laboratory at weekly wages.

    Davy held the joint office of Professor of Chemistry and
    Director of the Laboratory; he ultimately gave up the former to
    the late Professor Brande, but he insisted that Faraday should
    be appointed Director of the Laboratory, and, as Faraday told
    me, this enabled him on subsequent occasions to hold a definite
    position in the Institution, in which he was always supported
    by Davy. I believe he held that office to the last.

                    Believe me, my dear Tyndall, yours truly,
                                                    J. P. GASSIOT.


In 1808 Mr. Tatum had founded a City Philosophical Society.[8] It
consisted of thirty or forty young men in humble or moderate rank, who
met on Wednesdays for mutual instruction; lectures being given once
a fortnight by the members in turn. Tatum introduced Faraday to this
Society in 1813. Edward Magrath was secretary. Amongst Faraday’s notes
of his life is the following:--

    During this spring Magrath and I established the
    mutual-improvement plan, and met at my rooms up in the attics
    of the Royal Institution, or at Wood Street at his warehouse.
    It consisted perhaps of half-a-dozen persons, chiefly from
    the City Philosophical Society, who met of an evening to read
    together, and to criticise, correct, and improve each other’s
    pronunciation and construction of language. The discipline was
    very sturdy, the remarks very plain and open, and the results
    most valuable. This continued for several years.

[Sidenote: AT WORK IN CHEMISTRY.]

He writes, after a week of work at the Royal Institution, to Abbott:--

                              Royal Institution, March 8, 1813.

    It is now about nine o’clock, and the thought strikes me that
    the tongues are going both at Tatum’s and at the lecture in
    Bedford Street; but I fancy myself much better employed than
    I should have been at the lecture at either of those places.
    Indeed, I have heard one lecture already to-day, and had a
    finger in it (I can’t say a hand, for I did very little). It
    was by Mr. Powell, on mechanics, or rather on rotatory motion,
    and was a pretty good lecture, but not very fully attended.

    As I know you will feel a pleasure in hearing in what I have
    been or shall be occupied, I will inform you that I have been
    employed to-day, in part, in extracting the sugar from a
    portion of beetroot, and also in making a compound of sulphur
    and carbon--a combination which has lately occupied in a
    considerable degree the attention of chemists.

    With respect to next Wednesday, I shall be occupied until late
    in the afternoon by Sir H. Davy, and must therefore decline
    seeing you at that time; this I am the more ready to do as I
    shall enjoy your company next Sunday, and hope to possess it
    often in a short time.

The next letter to Abbott, dated April 9, recounts an explosion in
which both he and Sir Humphry Davy received considerable injury.
In June he wrote to Abbott four very remarkable letters concerning
lectures and lecturers. He had already heard Tatum and Davy, and had
now assisted Brande and Powell in their lectures, and had keenly
observed their habits, peculiarities, and defects, as well as the
effects they produced on the audience. He writes without the slightest
suspicion of suggestion that he himself has any likelihood of becoming
a lecturer, and says that he does not pretend to any of the requisites
for such an office. “If I am unfit for it,” he says, “’tis evident
that I have yet to learn; and how learn better than by the observation
of others? If we never judge at all, we shall never judge right.” “I,
too, have inducements in the C[ity] P[hilosophical] S[ociety] to draw
me forward in the acquisition of a small portion of knowledge on this
point.” “I shall point out but few beauties or few faults that I have
not witnessed in the presence of a numerous assembly.”

He begins by considering the proper shape of a lecture-room; its proper
ventilation, and need of suitable entrances and exits. Then he goes
on to consider suitability of subjects and dignity of subject. In the
second of the letters he contrasts the perceptive powers of the eye and
ear, and the proper arrangements for a lecturer’s table; then considers
diagrams and illustrations. The third letter deals with the delivery
and style of the lecture, the manner and attitudes of the lecturer, his
methods of keeping alive the attention of the audience, and duration of
the discourse. In the fourth of these letters (see p. 228), he dwells
on the mistakes and defects of lecturers, their unnecessary apologies,
the choice of apt experiments, and avoidance of trivialities.

[Sidenote: PROPOSALS FOR FOREIGN TRAVEL.]

In September, 1813, after but six months of work in the laboratory,
a proposition came to him from Sir Humphry Davy which resulted in
a complete change of scene. It was an episode of foreign travel,
lasting, as it proved, eighteen months. In the autobiographical notes
he wrote:--

    In the autumn Sir H. Davy proposed going abroad, and offered
    me the opportunity of going with him as his amanuensis, and
    the promise of resuming my situation in the Institution upon
    my return to England. Whereupon I accepted the offer, left the
    Institution on October 13, and, after being with Sir H. Davy in
    France, Italy, Switzerland, the Tyrol, Geneva, &c., in that and
    the following year, returned to England and London April 23,
    1815.

Before he left England, on September 18, 1813, at the request of
his mother, he wrote to an uncle and aunt the following account of
himself:--

    I was formerly a bookseller and binder, but am now turned
    philosopher, which happened thus:--Whilst an apprentice, I,
    for amusement, learnt a little of chemistry and other parts
    of philosophy, and felt an eager desire to proceed in that
    way further. After being a journeyman for six months, under
    a disagreeable master, I gave up my business, and, by the
    interest of Sir H. Davy, filled the situation of chemical
    assistant to the Royal Institution of Great Britain, in
    which office I now remain, and where I am constantly engaged
    in observing the works of Nature and tracing the manner in
    which she directs the arrangement and order of the world. I
    have lately had proposals made to me by Sir Humphry Davy to
    accompany him, in his travels through Europe and into Asia, as
    philosophical assistant. If I go at all I expect it will be
    in October next, about the end, and my absence from home will
    perhaps be as long as three years. But as yet all is uncertain.
    I have to repeat that, even though I may go, my path will not
    pass near any of my relations, or permit me to see those whom I
    so much long to see.

To Faraday, who was now twenty-two years old, foreign travel meant much
more than to most young men of equal age. With his humble bringing
up and slender resources, he had never had the chance of seeing the
outside world; he had never, to his own recollection, even seen the
sea. When on Wednesday, October 13, he started out on the journey
to Plymouth, in order to cross to the port of Morlaix, he began his
journal of foreign travel thus:--

    This morning formed a new epoch in my life. I have never
    before, within my recollection, left London at a greater
    distance than twelve miles.

[Sidenote: A NEW ELEMENT.]

This journal he kept with minute care, with the sole purpose of
recalling events to his mind. It gives full details as to Davy’s
scientific friends and work, intermingled with graphic descriptions
of scenery; and is remarkable also for its personal reticence. As
with many another, so with Faraday, foreign travel took in his life
the place of residence at a University. In France, in Italy, he
received enlarged ideas; and what he saw of learned men and academies
of science exercised no small formative effect upon one then at the
most impressionable age. He comments gaily on the odd incidents of
travel; the luminescence of the sea at night; the amazing fuss at the
Custom House; the postilion with his jack-boots, whip, and pouch; the
glow-worm (the first glow-worm he had ever seen); and the slim pigs of
Normandy. At Paris he visits the Louvre, where his chief comment on
its treasures is, that by their acquisition France has made herself
“a nation of thieves.” He goes to the Prefecture of Police for his
passport, in which he is described as having “a round chin, a brown
beard, a large mouth, a great nose,” etc. He visits the churches,
where the theatrical air pervading the place “makes it impossible to
attach a serious or important feeling to what is going on.” He comments
on the wood fires, the charcoal used in cooking, the washerwomen on
the river bank, the internal decorations of houses, the printing of
the books. Then he goes about with Davy amongst the French chemists.
Ampère, Clément, and Désormes come to Davy to show him the new and
strange substance “X,” lately discovered by M. Courtois. They heat
it, and behold it rise in vapour of a beautiful violet colour. Ampère
himself, on November 23rd, gives Davy a specimen. They carefully note
down its characters. Davy and his assistant make many new experiments
on it. At first its origin is kept a profound secret by the Frenchman.
Then it transpires that it is made from ashes of seaweed. They work
on it at Chevreul’s laboratory. Faraday borrows a voltaic pile from
Chevreul. With that intuition which was characteristic of him, Davy
jumps almost at once to a conclusion as to the nature of the new body,
which for nearly two years had been in the hands of the Frenchmen
awaiting elucidation. When he leaves Paris, they do not wholly
bless his rapidity of thought. But Faraday has seen--with placid
indifference--a glimpse of the great Napoleon “sitting in one corner
of his carriage, covered and almost hidden by an enormous robe of
ermine, and his face overshadowed by a tremendous plume of feathers,
that descended from a velvet hat”; he has also met Humboldt, and he has
heard M. Gay Lussac lecture to about two hundred pupils.

Dumas has recorded in his “Éloge Historique” a reflection of the
impressions left by the travellers. After speaking of the criticism to
which Davy was exposed during his visit, he says:--

    His laboratory assistant, long before he had won his great
    celebrity by his works, had by his modesty, his amiability,
    and his intelligence, gained most devoted friends at Paris,
    at Geneva, at Montpellier. Amongst these may be named in the
    front rank M. de la Rive, the distinguished chemist, father of
    the illustrious physicist whom we count amongst our foreign
    associates. The kindnesses with which he covered my youth
    contributed not a little to unite us--Faraday and myself.
    With pleasure we used to recall that we made one another’s
    acquaintance under the auspices of that affectionate and
    helpful philosopher whose example so truly witnessed that
    science does not dry up the heart’s blood. At Montpellier,
    beside the hospitable hearth of Bérard, the associate of
    Chaptal, doyen of our corresponding members, Faraday has left
    memories equally charged with an undying sympathy which his
    master could never have inspired. We admired Davy, we loved
    Faraday.

It is December 29 when the travellers leave Paris and cross the forest
of Fontainebleau. Faraday thinks he never saw a more beautiful scene
than the forest dressed in an airy garment of crystalline hoar frost.
They pass through Lyons, Montpellier, Aix, Nice, searching on the
way for iodine in the sea-plants of the Mediterranean. At the end
of January, 1814, they cross the Col de Tende over the snow at an
elevation of 6,000 feet into Italy, and find themselves in the midst
of the Carnival at Turin. They reach Genoa, and go to the house of a
chemist to make experiments on the _raia torpedo_, the electric skate,
trying to ascertain whether water could be decomposed by the electrical
discharges of these singular fishes. From Genoa they go by sea to
Lerici in an open boat, with much discomfort and fear of ship-wreck;
and thence by land to Florence.

[Sidenote: WITH DAVY IN ITALY.]

At Florence he goes with Davy to the Accademia del Cimento. He sees the
library, the gardens, the museum. Here is Galileo’s own telescope--a
simple tube of paper and wood, with lenses at each end--with which he
discovered Jupiter’s satellites. Here is the great burning glass of the
Grand Duke of Tuscany. And here is a numerous collection of magnets,
including one enormous loadstone supporting a weight of 150 pounds.
They make “the grand experiment of burning the diamond” in oxygen by
the sun’s heat concentrated through the Grand Duke’s burning glass.
They find the diamond to be pure carbon. Then early in April they
depart for Rome.

From Rome Faraday wrote to his mother a long chatty letter summarising
his travels, and sending messages of kindly remembrance to his
old master Riebau and others. He tells how, in spite of political
troubles, Sir Humphry Davy’s high name has procured them free admission
everywhere, and how they have just heard that Paris has been taken by
the Allied troops.

At Rome they witness unconvinced some attempts of Morichini to impart
magnetism to steel needles by the solar rays. They pass the Colosseum
by moonlight, making an early morning start across the Campagna, on
the road to Naples, with an armed guard for fear of brigands. Twice,
in the middle of May, they ascend Vesuvius, the second time during a
partial eruption rendered all the more vivid by the lateness of the
hour--half-past seven--at which the edge of the crater was reached. In
June they visit Terni, and note the nearly circular rainbow visible in
the spray of the cataract; and so across the Apennines to Milan.

At Milan occurs the following entry:--

    Friday 17th [June, 1814], Milan. Saw M. Volta, who came to Sir
    H. Davy, an hale elderly man, bearing the red ribbon, and very
    free in conversation.

He does _not_ record how the ceremonious old Count, who had specially
attired himself in his Court uniform to welcome the illustrious
chemist, was horrified at the informal manners and uncourtly dress of
the tourist philosopher.

So, travelling by Como and Domo d’Ossola, they come to Geneva, and
here remain a long time; and Faraday writes again to his mother and
to Abbott. He can even find time to discuss with the latter the
relative merits of the French and Italian languages, and the trend of
civilisation in Paris and in Rome. Twice he sends messages to Riebau.
One of his letters to Abbott, in September, contains passages of more
than transient interest:--

    Some doubts have been expressed to me lately with respect
    to the continuance of the Royal Institution; Mr. Newman can
    probably give a guess at the issue of them. I have three boxes
    of books, &c., there, and I should be sorry if they were lost
    by the turning up of unforeseen circumstances; but I hope all
    will end well (you will not read this out aloud). Remember
    me to all friends, if you please. And “now for you and I to
    ourselves.”...

    In passing through life, my dear friend, everyone must expect
    to receive lessons, both in the school of prosperity and in
    that of adversity; and, taken in a general sense, these schools
    do not only include riches and poverty, but everything that
    may cause the happiness and pleasure of man, and every feeling
    that may give him pain. I have been in at the door of both
    these schools; nor am I so far on the right hand at present
    that I do not get hurt by the thorns on my left. With respect
    to myself, I have always perceived (when, after a time, I saw
    things more clearly) that those things which at first appeared
    as misfortunes or evils ultimately were actually benefits,
    and productive of much good in the future progress of things.
    Sometimes I compared them to storms and tempests, which cause a
    temporary disarrangement to produce permanent good; sometimes
    they appeared to me like roads--stony, uneven, hilly, and
    uncomfortable, it is true--but the only roads to a good beyond
    them; and sometimes I said they were clouds which intervened
    between me and the sun of prosperity, but which I found were
    refreshing, reserving to me that tone and vigour of mind which
    prosperity alone would enervate and ultimately destroy....

    [Sidenote: HINTS OF DISCOMFORT.]

    You talk of travelling, and I own the word is seducing, but
    travelling does not secure you from uneasy circumstances. I
    by no means intend to deter you from it; for though I should
    like to find you at home when I come home, and though I know
    how much the loss would be felt by our friends, yet I am aware
    that the fund of knowledge and of entertainment opened would
    be almost infinite. But I shall set down a few of my own
    thoughts and feelings, &c., in the same circumstances. In the
    first place, then, my dear B., I fancy that when I set my foot
    in England I shall never take it out again; for I find the
    prospect so different from what it at first appeared to be,
    that I am certain, if I could have foreseen the things that
    have passed, I should never have left London. In the second
    place, enticing as travelling is--and I appreciate fully its
    advantages and pleasures--I have several times been more
    than half decided to return hastily home; but second thoughts
    have still induced me to try what the future may produce, and
    now I am only retained by the wish of improvement. I have
    learned just enough to perceive my ignorance, and, ashamed of
    my defects in everything, I wish to seize the opportunity of
    remedying them. The little knowledge I have gained in languages
    makes me wish to know more of them, and the little I have
    seen of men and manners is just enough to make me desirous of
    seeing more; added to which, the glorious opportunity I enjoy
    of improving in the knowledge of chemistry and the sciences
    continually determines me to finish this voyage with Sir
    Humphry Davy. But if I wish to enjoy those advantages, I have
    to sacrifice much; and though those sacrifices are such as an
    humble man would not feel, yet I cannot quietly make them.
    Travelling, too, I find, is almost inconsistent with religion
    (I mean modern travelling), and I am yet so old-fashioned as
    to remember strongly (I hope perfectly) my youthful education;
    and upon the whole, _malgré_ the advantages of travelling, it
    is not impossible but that you may see me at your door when you
    expect a letter.

    You will perceive, dear B., that I do not wish you hastily
    to leave your present situation, because I think that a
    hasty change will only make things worse. You will naturally
    compare your situation with others you see around you, and
    by this comparison your own will appear more sad, whilst the
    others seem brighter than in truth they are; for, like the two
    poles of a battery, the ideas of each will become exalted by
    approaching them. But I leave you, dear friend, to act in this
    case as your judgment may direct, hoping always for the best.

       *       *       *       *       *

    Sir Humphry works often on iodine, and has lately been making
    experiments on the prismatic spectrum at M. Pictet’s. They
    are not yet perfected, but from the use of very delicate air
    thermometers, it appears that the rays producing most heat are
    certainly out of the spectrum and beyond the red rays. Our time
    has been employed lately in fishing and shooting; and many a
    quail has been killed in the plains of Geneva, and many a
    trout and grayling have been pulled out of the Rhone.

       *       *       *       *       *

    I need not say, dear Ben, how perfectly I am yours,

                                        M. FARADAY.


[Sidenote: ARISTOCRATIC HAUTEUR.]

This letter reveals, what the diary of travel so scrupulously hides,
the existence of circumstances which were hardly tolerable in Faraday’s
position. To make the reference intelligible it should be remembered
that Davy, who had come up to London in 1801 as a raw youth, of immense
ability but very uncouth exterior, had developed into a fashionable
person, had become the idol of the hour, had married a very wealthy
widow, had been knighted, and had given himself up very largely to the
pursuits of fashionable society and to the company of the aristocratic
_beau monde_. Lady Davy accompanied Sir Humphry in this Continental
tour; and though Faraday had been taken with them as secretary and
scientific assistant, it would seem that he had not always been
treated with the respect due to one in that position. The above letter
evidently disquieted Abbott, for he wrote back to Faraday to inquire
more closely into his personal affairs, telling him he was sure he
was not happy, and asking him to share his difficulties. Faraday, who
was now back in Rome, replied in January in a long letter of twelve
pages,[9] which he says he had intended to fill with an account of
the waterfalls he had seen, but which gives instead a detailed account
of his vexations. He had, he said, written his former letter when
in a ruffled state of mind. He now gives the explanation. Before,
however, this letter could reach Abbott, the latter had written yet
more urgently to know what was the matter. To this Faraday replied
on February 23rd. As this shorter letter summarises the previous one
it may be given here. Both are printed in Bence Jones’s “Life and
Letters”:--

                                        Rome, February 23, 1815.

    DEAR B----,--In a letter of above twelve pages I gave answers
    to your question respecting my situation. It was a subject
    not worth talking about, but I consider your inquiries as so
    many proofs of your kindness and the interest you take in my
    welfare, and I thought the most agreeable thanks I could make
    you would be to answer them. The same letter also contained a
    short account of a paper written by Sir Humphry Davy on ancient
    colours, and some other miscellaneous matters.

    [Sidenote: SECRET OF MORTIFICATION.]

    I am quite ashamed of dwelling so often on my own affairs,
    but as I know you wish it, I shall briefly inform you of my
    situation. I do not mean to employ much of this sheet of paper
    on the subject, but refer you to the before-mentioned long
    letter for clear information. It happened a few days before we
    left England, that Sir H.’s valet declined going with him, and
    in the short space of time allowed by circumstances another
    could not be got. Sir H. told me he was very sorry, but that,
    if I would do such things as were absolutely necessary for him
    until he got to Paris, he should there get another. I murmured,
    but agreed. At Paris he could not get one. No Englishmen were
    there, and no Frenchman fit for the place could talk English
    to me. At Lyons he could not get one; at Montpellier he could
    not get one; nor at Genoa, nor at Florence, nor at Rome, nor
    in all Italy; and I believe at last he did not wish to get one:
    and we are just the same now as we were when he left England.
    This of course throws things into my duty which it was not
    my agreement, and is not my wish, to perform, but which are,
    if I remain with Sir H., unavoidable. These, it is true, are
    very few; for having been accustomed in early years to do for
    himself, he continues to do so at present, and he leaves very
    little for a valet to perform; and as he knows that it is not
    pleasing to me, and that I do not consider myself as obliged
    to do them, he is always as careful as possible to keep those
    things from me which he knows would be disagreeable. But Lady
    Davy is of another humour. She likes to show her authority,
    and at first I found her extremely earnest in mortifying me.
    This occasioned quarrels between us, at each of which I gained
    ground, and she lost it; for the frequency made me care nothing
    about them, and weakened her authority, and after each she
    behaved in a milder manner. Sir H. has also taken care to get
    servants of the country, ycleped _lacquais de place_, to do
    everything she can want, and now I am somewhat comfortable;
    indeed, at this moment I am perfectly at liberty, for Sir H.
    has gone to Naples to search for a house or lodging to which we
    may follow him, and I have nothing to do but see Rome, write my
    journal, and learn Italian.

    But I will leave such an unprofitable subject, and tell you
    what I know of our intended route. For the last few weeks
    it has been very undecided, and at this moment there is no
    knowing which way we shall turn. Sir H. intended to see Greece
    and Turkey this summer, and arrangements were half made for
    the voyage; but he has just learned that a quarantine must be
    performed on the road there, and to do this he has an utter
    aversion, and that alone will perhaps break up the journey.

       *       *       *       *       *

    Since the long letter I wrote you, Sir H. has written two short
    papers for the Royal Society--the first on a new solid compound
    of iodine and oxygen, and the second a new gaseous compound of
    chlorine and oxygen, which contains four times as much oxygen
    as euchlorine.

    The discovery of these bodies contradicts many parts of
    Gay-Lussac’s paper on iodine, which has been very much vaunted
    in these parts. The French chemists were not aware of the
    importance of the subject until it was shown to them, and now
    they are in haste to reap all the honours attached to it; but
    their haste opposes their aim. They reason theoretically,
    without demonstrating experimentally, and errors are the result.

       *       *       *       *       *

                    I am, my dear Friend, yours ever and faithfully,
                                                           M. FARADAY.


The equivocal position thus forced upon Faraday by the _hauteur_ of
Lady Davy nearly caused a _contretemps_ during the stay at Geneva,
which lasted from the end of June, 1814, to about the middle of
September. Bence Jones’s account, derived from Faraday himself, is
as follows:--Professor G. de la Rive, undazzled by the brilliancy of
Davy’s reputation, was able to see the true worth of his assistant.
Davy was fond of shooting, and Faraday, who accompanied them, used to
load Davy’s gun for him, while De la Rive loaded his own. Entering
into conversation with Faraday, De la Rive was astonished to find that
the intelligent and charming young man whom he had taken hitherto
for a domestic was really _préparateur de laboratoire_ in the Royal
Institution. This led him to place Faraday, in one respect, on an
equality with Davy. Whilst they were staying in his house, he wished
them to dine together at his table. Davy, it is said, declined, because
Faraday acted in some things as his servant. De la Rive expressed his
feelings strongly, and ordered dinner in a separate room for Faraday.
A rumour spread years after that De la Rive gave a dinner in Faraday’s
honour: this is not so, however.

[Sidenote: VISIT TO GENEVA.]

Of that Geneva visit Faraday says, in 1858, to M. A. de la Rive:--

    I have some such thoughts (of gratitude) even as regards your
    own father, who was, I may say, the first who personally at
    Geneva, and afterwards by correspondence, encouraged and by
    that sustained me.

This correspondence, which began with the father and was continued with
the son, lasted altogether nearly fifty years.

From Geneva the travellers went northward, by Lausanne, Vevay, Bern,
Zürich, and Schaffhausen, across Baden and Würtemburg to Munich. After
visiting this and other German towns, they crossed Tyrol southwards to
Vicenza, halting in the neighbourhood of the Pietra Mala to collect the
inflammable gas which there rises from the soil. They spent a day in
Padua, and three days in Venice; and on by Bologna to Florence, where
Davy completed his analysis of the gas collected at Pietra Mala. Early
in November they were again in Rome. He writes once and again to his
mother, while his anxiety about the Royal Institution makes him send
inquiries to Abbott as to what is going to happen there, and to charge
him, “if any change should occur in Albemarle Street,” not to forget
his books which are lying there. “I prize them now more than ever.”

To his former master, Riebau, he wrote from Rome as follows:--

                                        Rome, Jan. 5th, 1815.

                                        HONOURED SIR,

    It is with very peculiar but very pleasing and indeed
    flattering sentiments that I commence a letter intended for
    you, for I esteem it as a high honour that you should not only
    allow but even wish me to write to you. During the whole of
    the short eight years that I was with you, Sir, and during
    the year or two that passed afterwards before I left England,
    I continually enjoyed your goodness and the effects of it;
    and it is gratifying to me in the highest degree to find that
    even absence has not impaired it, and that you are willing to
    give me the highest proof of (allow me to say) friendship that
    distance will admit. I have received both the letters that you
    have wrote to me, Sir, and consider them as far from being the
    least proofs of your goodwill and remembrance of me. Allow
    me to thank you humbly but sincerely for these and all other
    kindness, and I hope that at some future day an opportunity
    will occur when I can express more strongly my gratitude.

    I beg leave to return a thousand thanks to my kind Mistress,
    to Mr. and Mrs. Paine and George for their remembrances, and
    venture to give mine with respect in return. I am very glad to
    hear that all are well. I am very much afraid you say too much
    of me to Mr. Dance, Mr. Cosway, Mrs. Udney, etc., for I feel
    unworthy of what you have said of me formerly, and what you
    may say now. Since I have left England, the experience I have
    gained in more diversified and extended life, and the knowledge
    I have gained of what is to be learned and what others know,
    have sufficiently shown me my own ignorance, the degree in
    which I am surpassed by all the world, and my want of powers;
    but I hope that at least I shall return home with an addition
    to my self-knowledge. When speaking of those who are so much
    my superiors, as Mr. Dance, Mr. Cosway, and Mrs. Udney, etc.,
    I feel a continual fear that I should appear to want respect,
    but the manner in which you mention their names in your letter
    emboldens me to beg that you will give my humblest respects
    to those honored persons, if, and only if (I am afraid of
    intruding) they should again speak of me to you. Mr. Dance’s
    kindness claims my gratitude, and I trust that my thanks, the
    only mark that I can give, will be accepted.

    [Sidenote: BOOKS AND BOOKSELLERS.]

    Since I have been abroad, my old profession of books has
    oftentimes occurred to my mind and been productive of much
    pleasure. It was my wish at first to purchase some useful book
    at every large town we came to, but I found my stock increase
    so fast that I was obliged to alter my plan and purchase only
    at Capital Cities. The first books that I wanted were grammars
    and dictionaries, but I found few places like London where I
    could get whatever I wanted. In France (at the time we were
    there) English books were very scarce, and also English and
    French books; and a French grammar for an Englishman was a
    thing difficult to find. Nevertheless the shops appeared well
    stocked with books in their own language, and the encouragement
    Napoleon gave to Arts and Sciences extended its influence even
    to the printing and binding of books. I saw some beautiful
    specimens in both these branches at the Bibliothèque Impériale
    at Paris, but I still think they did not exceed or even equal
    those I had seen in London before. We have as yet seen very
    little of Germany, having passed rapidly through Switzerland
    and stopping but a few days at Munich, but that little gave
    me a very favorable idea of the Booksellers’ shops. I got an
    excellent English and German dictionary immediately I asked for
    it, and other books I asked for I found were to be had, but E.
    and G. Grammars were scarce, owing to the little communication
    between the two Empires, and the former power of the French
    in Germany. Italy I have found the country furnished with
    the fewest means--if books are the means of disseminating
    knowledge, and even Venice which is renowned for Printing
    appeared to me bare and little worthy of its character. It is
    natural to suppose that the great and most estimable use of
    printing is to produce those books which are in most general
    use and which are required by the world at large; it is those
    books which form this branch of trade, and consequently every
    shop in it gives an account of the more valuable state of the
    art (_i.e._) the use made of it. In Italy there are many
    books, and the shelves of the shops there appear full, but the
    books are old, or what is new have come from France; they seem
    latterly to have resigned printing and to have become satisfied
    with the libraries their forefathers left them. I found at
    Florence an E. and I. Grammar (Veneroni’s), which does a little
    credit to Leghorn; but I have searched unsuccessfully at Rome,
    Naples, Milan, Bologna, Venice, Florence, and in every part of
    Italy for and E. and I. Dictionary, and the only one I could
    get was Rollasetti in 8vo. E. F. and I. A circumstance still
    more singular is the want of bibles; even at Rome, the seat of
    the Roman Catholic faith, a bible of moderate size is not to
    be found, either Protestant or Catholic. Those which exist are
    large folios or 4tos and in several volumes, interspersed with
    the various readings and commentaries of the fathers, and they
    are in the possession of the Priests and religious professors.
    In all shops at Rome where I ask for a small pocket bible the
    man seemed afraid to answer me, and some Priest in the shop
    looked at me in a very inquisitive way.

    I must now, Kind Sir, put an end to this letter, which I fear
    you will think already too long. I beg you will have the
    goodness to send to my Mother and say I am well, and give my
    duty to her and my love to my brother and sisters. I have
    wrote four or five times lately from Rome to various friends.
    Remember me, if you please, to Mr. Kitchen, and others who may
    enquire after me. I thank you for your concluding wishes and
    am, Sir,

                                        Your most dutifully,
                                                        FARADAY.


To his sisters he wrote also. To the elder, on the Church festivals,
the Carnival, and the ruins of the Colosseum. To the younger, on the
best way of learning French. His diary is full of the Carnival, the
foolishness of which afforded him much amusement. He witnessed the
horse-races in the Corso, went four times to masked balls, where his
boyish love of uproarious fun broke out beyond restraint, for to the
last one he went disguised in a night-gown and night-cap. Between
gaieties in the evenings and chemical experiments with Davy in the
day, his time must have been pretty fully occupied. They had had the
intention of going on to Greece and Turkey, but owing to dread of
quarantine these projects were abandoned, and at the end of February,
1815, they moved southwards to Naples. Here is a characteristic entry:--

    Tuesday, March 7th.--I heard for news that Bonaparte was again
    at liberty. Being no politician, I did not trouble myself much
    about it, though I suppose it will have a strong influence on
    the affairs of Europe.

He went with Sir Humphry to explore Monte Somma, and ventured to make
another ascent of the cone of Vesuvius, with the gratification of
finding the crater in much greater activity than during the visits of
the preceding year.

[Sidenote: THE END OF THE TOUR.]

Then, for reasons not altogether clear, the tour was suddenly cut
short. Naples was left on March 21st, Rome on 24th, Mantua was passed
on 30th. Tyrol was recrossed, Germany traversed by Stuttgardt,
Heidelberg, and Cologne. Brussels was reached on 16th April, whence
London was regained _viâ_ Ostend and Deal. A letter written from
Brussels to his mother positively overflows with the joy of expected
return. He does not want his mother to be inquiring at Albemarle Street
as to when he is expected:--

    You may be sure that my first moments will be in your company.
    If you have opportunities, tell some of my dearest friends,
    but do not tell everybody--that is, do not trouble yourself to
    do it. I am of no consequence except to a few, and there are
    but a few that are of consequence to me, and there are some
    whom I should like to be the first to tell myself--Mr. Riebau
    for one. However, let A. know, if you can...

    Adieu till I see you, dearest Mother; and believe me ever your
    affectionate and dutiful son,

                                        M. FARADAY.

    [P.S.] ’Tis the shortest and (to me) the sweetest letter I ever
    wrote you.

A fortnight after his return to London, Faraday was re-engaged, at
a salary of thirty shillings a week, at the Royal Institution as
assistant in the laboratory and mineralogical collection. He returned
to the scene of his former labours; but with what widened ideas! He
had had eighteen months of daily intercourse with the most brilliant
chemist of the age. He had seen and conversed with Ampère, Arago,
Gay-Lussac, Chevreul, Dumas, Volta, De la Rive, Biot, Pictet, De
Saussure, and De Stael. He had formed a lasting friendship with more
than one of these. He had dined with Count Rumford, the founder of
the Royal Institution. He had gained a certain mastery over foreign
tongues, and had seen the ways of foreign society. Though it was many
years before he again quitted England for a foreign tour, he cherished
the most lively recollection of many of the incidents that had befallen
him.




CHAPTER II.

LIFE AT THE ROYAL INSTITUTION.


Amongst the scientific societies of Great Britain, the Royal
Institution of London occupies a conspicuous place. It has had many
imitators in its time, yet it remains unique. A “learned society”
it may claim to be, in the sense that it publishes scientific
transactions, and endeavours to concentrate within itself and promote
the highest science, within a certain range of subjects. In some
respects it resembles a college; for it appoints professors, and
provides them with space, appliances, and materials for research, and a
theatre wherein to lecture. For its members it provides a comfortable,
well-stocked library, and a reading-room where daily and periodic
journals may be consulted. But it has achieved a reputation far in
excess of any it would have held, had that reputation depended solely
on its publications, or on the numerical strength of its membership.

Founded in the year 1799 by that erratic genius Count Rumford, as a
sort of technical school,[10] it would speedily have come to an end
had not others stepped in to develop it in new ways. From the certain
ruin which seemed impending in 1801, it was saved by the appearance
upon the scene of the brilliant youth Humphry Davy, whose lectures
made it for ten years the resort of fashion. In 1814 it was again in
such low water that Faraday, travelling on the Continent at that time
as amanuensis to Sir Humphry, was every month expecting to hear of its
collapse. Until about 1833, when the two Fullerian Professorships were
founded, it was continually in financial difficulties. The persistent
and extraordinary efforts made by Faraday from 1826 to 1839, and
the reputation of the place which accrued by his discoveries, were
beyond all question its salvation from ruin. When it was founded it
was located in two private houses in Albemarle Street, then regarded
as quite out of town, if not almost suburban; the premises being
altered and an entrance hall with staircase added. A little later the
lecture-theatre, much as it still exists, was constructed. The exterior
at first remained unchanged. The stucco pilasters of Grecian style,
which give it its air of distinction, were not erected until 1838.
The fine rooms of the Davy-Faraday laboratory at the south end were
only added in 1896 by the liberality of Mr. Ludwig Mond. Besides the
laboratories for research in physical chemistry, which have thus been
associated with the older part of the Institution, additional rooms for
the library have been provided in this munificent gift to science. The
older laboratories of the Institution, though they retain some features
from Rumford’s time, have been considerably remodelled. The old rooms
where Davy, Young, Brande, Faraday, Frankland, and Tyndall conducted
their researches are still in existence; but the chief laboratory was
reconstructed in 1872 in Tyndall’s time; and it has been quite recently
enlarged and reconstructed to accommodate the heavy machinery required
in Professor Dewar’s researches on liquid air and the properties of
bodies at low temperatures.

The spirit of the place may be summed up very briefly. It has existed
for a century as the home of the highest kind of scientific research,
and of the best and most specialised kind of scientific lectures.
It was here that Davy first showed the electric arc lamp; that he
astonished the world by decomposing potash and producing potassium;
that he invented the safety lamp. It was here that Faraday worked and
laboured for nearly fifty years. Here that Tyndall’s investigations
on radiant heat and diamagnetism were carried on. Here that Brande,
Frankland, Odling, Gladstone, and Dewar have handed on the torch
of chemistry from the time of Davy. Professorships, of which the
educational duties are restricted to a few lectures in the year,
giving leisure and scope for research as the main duty, are not to
be found anywhere else in the British Islands; those at colleges
and universities being invariably hampered with educational and
administrative duties.

[Sidenote: ROYAL INSTITUTION LABORATORIES.]

As for the lectures at the Royal Institution, they may be divided under
three heads: the afternoon courses; the juvenile lectures at Christmas;
the Friday night discourses. The afternoon lectures are thrice a week
at three o’clock, and consist usually of short courses, from three
lectures to as many as twelve, by eminent scientific and literary men.
Invariably one of these courses during the season, either before or
after Easter, is given by one of the regular Professors; the remaining
lecturers are paid professional fees in proportion to the duration of
their course. The Christmas lectures, always six in number, are given,
sometimes by one of the Professors, sometimes by outside lecturers
of scientific reputation. But the Friday night discourses, given at
nine o’clock, during the season from January till June, are unique.
No fee is paid to the lecturer, save a contribution toward expenses
if applied for, and it is considered to be a distinct honour to be
invited to give such a discourse. There is no scientific man of any
original claim to distinction; no chemist, engineer, or electrician; no
physiologist, geologist, or mineralogist, during the last fifty years,
who has not been invited thus to give an account of his investigations.
Occasionally a wider range is taken, and the eminent writer of books,
dramatist, metaphysician, or musician has taken his place at the
lecture-table. The Friday night gathering is always a brilliant one.
From the _salons_ of society, from the world of politics and diplomacy,
as well as from the ranks of the learned professions and of the fine
arts, men and women assemble to listen to the exposition of the latest
discoveries or the newest advances in philosophy by the men who have
made them. Every discourse must, so far as the subject admits, be
illustrated in the best possible way by experiments, by diagrams, by
the exhibition of specimens. Not infrequently, the person invited to
give a Friday evening discourse at the Royal Institution will begin
his preparations five or six months beforehand. At least one instance
is known--the occasion being a discourse by the late Mr. Warren De la
Rue--where the preparations were begun more than a year beforehand, and
cost several hundreds of pounds. And this was to illustrate a research
already made and completed, of which the bare scientific results had
already been communicated in a memoir to the Royal Society. A mere
enumeration of the eminent men who have thus given their time and
labours to the Royal Institution would fill many pages. It is little
cause for wonder then that the lecture-theatre at Albemarle Street is
crowded week after week in the pursuit of science under conditions like
these; or that every lecturer is spurred on by the spirit of the place
to do his subject the utmost justice by the manner in which he handles
it. There are no lectures so famous, in the best sense of the word so
popular, certainly none sustained at so high a level, as the lectures
of the Royal Institution.

[Sidenote: THE FAMOUS LECTURES.]

But it was not always thus. Davy’s brilliant but ill-balanced genius
had drawn fashionable crowds to the morning lectures which he gave.
Brande proved to be a much more humdrum lecturer; and though with young
Faraday at his elbow he found his work of lecturing a task “on velvet,”
he was not exactly an inspiring person. During Davy’s protracted tour
abroad things had not altogether prospered, and his return was none
too soon. Faraday threw himself whole-heartedly into the work of the
Institution, not only helping as lecture assistant, but giving a hand
also in the preparation of the _Quarterly Journal of Science_, which
had been established as a kind of journal of proceedings.

But now Faraday was to take a quiet step forward. He appears at the
City Philosophical Society in the character of lecturer. He gave
seven lectures there, in 1816, on chemistry, the fourth of them being
“On Radiant Matter.” Extracts are given from most of these lectures
in Bence Jones’s “Life and Letters of Faraday”; they show all that
love of accuracy, that philosophic suspense of judgment in matters of
hypothesis, which in after years were so characteristic of the man.

He also kept a commonplace book filled with notes of scientific
matters, with literary excerpts, anagrams, epitaphs, algebraic puzzles,
varieties of spelling of his own name, and personal experiences,
including a poetical diatribe against falling in love, together with
the following more prosaic aphorism:--

    What is Love?--A nuisance to everybody but the parties
    concerned. A private affair which every one but those concerned
    wishes to make public.

It also includes a piece in verse, by a member of the City
Philosophical Society--a Mr. Dryden--called “Quarterly Night,” which
is interesting as embalming a portrait of the youthful Faraday as he
appeared to his comrades:--

  Neat was the youth in dress, in person plain;
  His eye read thus, _Philosopher in grain_;
  Of understanding clear, reflection deep;
  Expert to apprehend, and strong to keep.
  His watchful mind no subject can elude,
  Nor specious arts of sophists ere delude;
  His powers, unshackled, range from pole to pole;
  His mind from error free, from guilt his soul.
  Warmth in his heart, good humour in his face,
  A friend to mirth, but foe to vile grimace;
  A temper candid, manners unassuming,
  Always correct, yet always unpresuming.
  Such was the youth, the chief of all the band;
  His name well known, Sir Humphry’s right hand.

At this date there were no evening duties at the Royal Institution, but
Faraday found his evenings well occupied, as he explains to Abbott when
rallied about his having deserted his old friend. Monday and Thursday
evenings he spent in self-improvement according to a regular plan.
Wednesdays he gave to “the Society” (_i.e._ the City Philosophical).
Saturdays he spent with his mother at Weymouth Street; leaving only
Tuesdays and Fridays for his own business and friends.

[Sidenote: CITY PHILOSOPHICAL SOCIETY.]

And so the busy months pass, and he gives more lectures in the privacy
of the City Society, one of them, “On some Observations on the Means
of obtaining Knowledge,” attaining the dignity of print at the hands
of Effingham Wilson, the enterprising City publisher, who a few
years later printed Browning’s “Paracelsus” and Alfred Tennyson’s
first volume, “Poems: Chiefly Lyrical.” By the time he has given
nine lectures he has gained confidence. The discourses had all been
written out beforehand, though never literally “read.” For the tenth
lecture--on Carbon--he wrote notes only. This is in July, 1817, and in
these notes he touches on a matter in which he had been very busily
aiding Sir Humphry Davy, the invention of the safety lamp. Many
of the early forms of experimental apparatus constructed, and some
of the early lamps, are still preserved in the museum of the Royal
Institution. Dr. Clanny had, in 1813, proposed an entirely closed lamp,
supplied with air from the mine, through water, by bellows. After many
experiments on explosive mixtures of gas and air, and on the properties
of flame, Davy adopted an iron-wire gauze protector for his lamp, which
was introduced into coal mining early in 1816. In Davy’s preface to
his work describing it, he says: “I am myself indebted to Mr. Michael
Faraday for much able assistance in the prosecution of my experiments.”

[Sidenote: A RIFT WITHIN THE LUTE.]

And well might Davy be grateful. With all his immense ability, he
was a man almost destitute of the faculties of order and method. He
had little self-control, and the fashionable dissipations which he
permitted himself lessened that little. Faraday not only kept his
experiments going, but made himself responsible for their records. He
preserved every note and manuscript of Davy’s with religious care.
He copied out Davy’s scrawled researches in a neat clear delicate
handwriting, begging only for his pains to be allowed to keep the
originals, which he bound in two quarto volumes. Faraday has been known
to remark to an intimate friend that amongst his advantages he had had
before him a model to teach him what he should avoid. But he was ever
loyal to Davy, earnest in his praise, and frank in his acknowledgment
of his debt to his master in science. Still there arose the little rift
within the lute. The safety lamp, great as was the practical advantage
it brought to the miner, is not safe in all circumstances. Davy did
not like to admit this, and would never acknowledge it. Examined before
a Parliamentary Committee as to whether under a certain condition
the safety lamp would become unsafe, Faraday admitted that this was
the case. Not even his devotion to his master would induce him to
hide the truth. He was true to himself in making the acknowledgment,
though it angered his master. One Friday evening at the Royal
Institution--probably about 1826--there was exhibited an improved Davy
lamp with a eulogistic inscription; Faraday added in pencil the words:
“The opinion of the inventor.”

At this time he began to give private lessons in chemistry to a pupil
to whom he had been recommended by Davy. His lectures at the City
Society in Dorset Street were continued in 1818, and at the conclusion
of those on chemistry he delivered one on “Mental Inertia,” which has
been recorded at some length by Bence Jones.

In 1818 he attended a course of lessons on oratory by the elocutionist
Mr. B. H. Smart, paying out of his slender resources half a guinea a
lesson, so anxious was he to improve himself, even in his manner of
lecturing. His notes on these lessons fill 133 manuscript pages.

His other notes now begin to partake less of the character of
quotations and excerpts, and more of the nature of queries or problems
for solution. Here are some examples:--

    “Do the pith balls diverge by the disturbance of electricity in
    consequence of mutual induction or not?”

    “Distil oxalate of ammonia. Query, results?”

    “Query, the nature of the body Phillips burns in his spirit
    lamp?”

The Phillips here mentioned was the chemist Richard Phillips
(afterwards President of the Chemical Society), one of his City
friends, whose name so frequently occurs in the correspondence of
Faraday’s middle life. Phillips busied himself to promote the material
interests of his friend who--to use his own language--was “constantly
engaged in observing the works of Nature, and tracing the manner in
which she directs the arrangement and order of the world,” on the
splendid salary of £100 per annum. The following note in a letter to
Abbott, dated February 27, 1818, reveals new professional labours:--

    I have been more than enough employed. We have been obliged
    even to put aside lectures at the Institution; and now I am so
    tired with a long attendance at Guildhall yesterday and to-day,
    being subpœnaed, with Sir H. Davy, Mr. Brande, Phillips, Aikin,
    and others, to give chemical information on a trial (which,
    however, did not come off), that I scarcely know what I say.

Shortly afterwards Davy again went abroad, but Faraday remained in
England. From Rome Davy wrote a note, the concluding sentence of which
shows how Faraday was advancing in his esteem:--

                                        Rome: October, 1818.

    Mr. Hatchett’s letter contained praises of you which were
    very gratifying to me; for, believe me, there is no one more
    interested in your success and welfare than your sincere
    well-wisher and friend,

                                        H. DAVY.


In the next year Davy wrote again, suggesting to Faraday that he might
possibly be asked to come to Naples as a skilled chemist to assist in
the unrolling of the Herculaneum manuscripts. In May he wrote again,
from Florence:--

    It gives me great pleasure to hear that you are comfortable at
    the Royal Institution, and I trust that you will not only do
    something good and honourable for yourself, but likewise for
    science.

    I am, dear Mr. Faraday, always your sincere friend and
    well-wisher,

                                        H. DAVY.


The wish that Davy expressed that Faraday might “do something”
for himself and likewise for science was destined soon to come to
fulfilment. But in the case of one who had worked so closely and had
been so intimately associated as an assistant, it must necessarily be
no easy matter always to draw a distinction between the work of the
master and that of the assistant. Ideas suggested by one might easily
have occurred to the other, when their thoughts had so long been
directed to the same ends. And so it proved.

[Sidenote: BEGINS ORIGINAL RESEARCHES.]

Reference to Chapter III. will show that already, beginning in 1816
with a simple analysis of caustic lime for Sir Humphry Davy, Faraday
had become an active worker in the domain of original research.
The fascination of the quest of the unknown was already upon him.
While working with and for Davy on the properties of flame and its
non-transmission through iron gauze, in the investigation of the
safety lamp, other problems of a kindred nature had arisen. One of
these, relating to the flow of gases through capillary tubes, Faraday
had attacked by himself in 1817. The subject formed one of the six
original papers which he published that year. In the next two years
he contributed in all no fewer than thirty-seven papers or notes to
the _Quarterly Journal of Science_. In 1819 began a long research on
steel which lasted over the year 1820. He had already given evidence
of that dislike of half-truths, that aversion for “doubtful knowledge”
which marked him so strongly. He had exposed, with quiet but unsparing
success, the emptiness of the claim made by an Austrian chemist to have
discovered a new metal, “Sirium,” by the simple device of analysing
out from the mass all the constituents of known sorts, leaving
behind--nothing.

[Sidenote: HE FALLS IN LOVE.]

And now, Faraday being twenty-nine years of age, a new and
all-important episode in his life occurred. Amongst the members of the
little congregation which met on Sundays at Paul’s Alley, Red Cross
Street, was a Mr. Barnard, a working silversmith of Paternoster Row,
an elder in the Sandemanian body. He had two sons, Edward Barnard, a
friend of Faraday’s, and George, who became a well-known water-colour
artist; and three daughters; one who was already at this time married;
Sarah, now twenty-one years of age; and Jane, who was still younger.
Edward had seen in Faraday’s note-book those boyish tirades against
falling in love, and had told his sister Sarah of them. Nevertheless,
in spite of all such misogynistic fancies, Faraday woke up one day to
find that the large-eyed, clear-browed girl had grown to a place in his
heart that he had thought barred against the assaults of love. She
asked him on one occasion to show her the rhymes against love in his
note-book. In reply he sent her the hitherto unpublished poem:--

                                            R. I.
                                        Oct. 11th, 1819.

  You ask’d me last night for the lines which I penn’d,
    When, exulting in ignorance, tempted by pride,
  I dared torpid hearts and cold breasts to commend,
    And affection’s kind pow’r and soft joys to deride.

  If you urge it I cannot refuse your request:
    Though to grant it will punish severely my crime:
  But my fault I repent, and my errors detest;
    And I hoped to have shown my conversion in time.

  Remember, our laws in their mercy decide
    That no culprit be forced to give proof of his deed:
  They protect him though fall’n, his failings they hide,
    And enable the wretch from his crimes to receed (_sic_).

  The principle’s noble! I need not urge long
    Its adoption; then turn from a judge to a friend.
  Do not ask for the proof that I once acted wrong,
    But direct me and guide me the way to amend.

                                        M. F.


What other previous passages between them are hinted at in the letter
which he sent her, is unknown; but on July 5, 1820, he wrote:--

                                        Royal Institution.

    You know me as well or better than I do myself. You know
    my former prejudices, and my present thoughts--you know my
    weaknesses, my vanity, my whole mind; you have converted me
    from one erroneous way, let me hope you will attempt to correct
    what others are wrong.

       *       *       *       *       *

    Again and again I attempt to say what I feel, but I cannot.
    Let me, however, claim not to be the selfish being that wishes
    to bend your affections for his own sake only. In whatever way
    I can best minister to your happiness either by assiduity or by
    absence, it shall be done. Do not injure me by withdrawing your
    friendship, or punish me for aiming to be more than a friend by
    making me less; and if you cannot grant me more, leave me what
    I possess, but hear me.

Sarah Barnard showed the letter to her father. She was young, and
feared to accept her lover. All her father would say by way of counsel
was that love made philosophers say many foolish things. The intensity
of Faraday’s passion proved for the time a bar to his advance. Fearing
lest she should be unable to return it with equal force, Miss Barnard
shrank from replying. To postpone an immediate decision, she went away
with her sister, Mrs. Reid, to Ramsgate. Faraday followed to press his
suit, and after several happy days in her company, varied with country
walks and a run over to Dover, he was able to say: “Not a moment’s
alloy of this evening’s happiness occurred. Everything was delightful
to the last moment of my stay with my companion, because she was so.”

Of the many letters that Faraday wrote to his future wife a number have
been preserved. They are manly, simple, full of quiet affection, but
absolutely free from gush or forced sentiment of any kind. Extracts
from several of them are printed by Bence Jones. One of these, written
early in 1821, runs as follows:--

    I tied up the enclosed key with my books last night, and make
    haste to return it lest its absence should occasion confusion.
    If it has, it will perhaps remind you of the disorder I must be
    in here also for the want of a key--I mean the one to my heart.
    However, I know where my key is, and hope soon to have it here,
    and then the Institution will be all right again. Let no one
    oppose my gaining possession of it when unavoidable obstacles
    are removed.

                    Ever, my dear girl, one who is perfectly yours,
                                                           M. FARADAY.


Faraday obtained leave of the managers to bring his wife to live in his
rooms at the Institution; and in May, 1821, his position was changed
from that of lecture assistant to that of superintendent of the house
and laboratory. In these changes Sir Humphry Davy gave him willing
assistance. But his salary remained £100 a year.

Obstacles being now removed, Faraday and Miss Barnard were married on
June 12. Few persons were asked to the wedding, for Faraday wished it
to be “just like any other day.” “There will,” he wrote, “be no bustle,
no noise, no hurry ... it is in the heart that we expect and look for
pleasure.”

[Sidenote: A HAPPY MARRIAGE.]

His marriage, though childless, was extremely happy. Mrs. Faraday
proved to be exactly the true helpmeet for his need; and he loved her
to the end of his life with a chivalrous devotion which has become
almost a proverb. Little indications of his attachment crop up in
unexpected places in his subsequent career; but as with his religious
views so with his domestic affairs, he never obtruded them upon others,
nor yet shrank from mentioning them when there was cause. Tyndall,
in after years, made the intensity of Faraday’s attachment to his
wife the subject of a striking simile: “Never, I believe, existed a
manlier, purer, steadier love. Like a burning diamond, it continued to
shed, for six and forty years, its white and smokeless glow.”

In his diploma-book, now in possession of the Royal Society, in which
he carefully preserved all the certificates, awards, and honours
bestowed upon him by academies and universities, there may be found on
a slip inserted in the volume this entry:--

                                        25th January, 1847.

    Amongst these records and events, I here insert the date of one
    which, as a source of honour and happiness, far exceeds the
    rest. We were _married_ on June 12, 1821.

                                        M. FARADAY.


And two years later, in the autobiographical notes he wrote:--

    On June 12, 1821, he married--an event which more than any
    other contributed to his earthly happiness and healthful state
    of mind. The union has continued for twenty-eight years, and
    has nowise changed, except in the depth and strength of its
    character.

When near the close of his life, he presented to the Royal Institution
the bookcase with the volumes of notes of Davy’s lectures and of books
bound by himself, the inscription recorded that they were the gift of
“Michael _and_ Sarah Faraday.”

Every Saturday evening he used to take his wife to her father’s
house at Paternoster Row, so that on Sunday they should be nearer to
the chapel at Paul’s Alley. And in after years, when he was away on
scientific work, visiting lighthouses, or attending meetings of the
British Association, he always tried to return for the Sunday.

A letter from Liebig in 1844 (see p. 225) gives one of the very few
glimpses of contemporary date of the impression made by Mrs. Faraday
upon others.

One month after his marriage Faraday made his profession of faith
before the Sandemanian church, to which his wife already belonged, and
was admitted a member. To his religious views, and his relations to the
body he thus formally joined, reference will be found later.

[Sidenote: FIRST ELECTRICAL DISCOVERY.]

Faraday now settled down to a routine life of scientific work. His
professional reputation was rising, and his services as analyst
were being sought after. But in the midst of this he was pursuing
investigations on his own account. In the late summer of this year
he made the discovery of the electro-magnetic rotations described in
Chapter III.--his first important piece of original research--and
had in consequence a serious misunderstanding with Dr. Wollaston. On
September 3rd, working with George Barnard in the laboratory, he saw
the electric wire for the first time revolve around the pole of the
magnet. Rubbing his hands as he danced around the table with beaming
face, he exclaimed: “There they go! there they go! we have succeeded
at last.” Then he gleefully proposed that they should wind up the day
by going to one of the theatres. Which should it be? “Oh, to Astley’s,
to see the horses.” And to Astley’s they went. On Christmas Day he
called his young wife to see something new: an electric conducting-wire
revolving under the influence of the magnetism of the earth alone.
He also read two chemical papers at the Royal Society, announcing new
discoveries; one of them in conjunction with his friend Phillips. In
July, 1822, he took his wife and her mother to Ramsgate, whilst he went
off with Phillips to Swansea to try a new process in Vivian’s copper
works. During this enforced parting, Faraday wrote his wife three
letters from which the following are extracts:---

[Sidenote: “A MERE LOVE-LETTER.”]

                                        (July 21, 1822).

    I perceive that if I give way to my thoughts, I shall write you
    a mere love-letter, just as usual, with not a particle of news
    in it: to prevent which I will constrain myself to a narrative
    of what has happened since I left you up to the present time,
    and then indulge my affection.

    Yesterday was a day of events--little, but pleasant. I went in
    the morning to the Institution, and in the course of the day
    analysed the water, and sent an account of it to Mr. Hatchett.
    Mr. Fisher I did not see. Mr. Lawrence called in, and behaved
    with his usual generosity. He had called in the early part of
    the week, and, finding that I should be at the Institution on
    Saturday only, came up, as I have already said, and insisted
    on my accepting two ten-pound bank-notes for the information
    he professed to have obtained from me at various times. Is not
    this handsome? The money, as you know, could not have been at
    any time more acceptable; and I cannot see any reason, my dear
    love, why you and I should not regard it as another proof,
    among many, that our trust should without a moment’s reserve be
    freely reposed on Him who provideth all things for His people.
    Have we not many times been reproached, by such mercies as
    these, for our caring after food and raiment and the things
    of this world? On coming home in the evening, _i.e._, coming
    to Paternoster Row home, I learned that Mr. Phillips had seen
    C., and had told her we should not leave London until Monday
    evening. So I shall have to-morrow to get things ready in,
    and I shall have enough to do. I fancy we are going to a large
    mansion and into high company, so I must take more clothes.
    Having the £20, I am become bold....

    And now, how do my dear wife and mother do? Are you
    comfortable? are you happy? are the lodgings convenient, and
    Mrs. O. obliging? Has the place done you good? Is the weather
    fine? Tell me all things as soon as you can. I think if you
    write directly you get this it will be best, but let it be a
    long letter. I do not know when I wished so much for a long
    letter as I do from you now. You will get this on Tuesday, and
    any letter from you to me cannot reach Swansea before Thursday
    or Friday--a sad long time to wait. Direct to me, Post Office,
    Swansea; or perhaps better, to me at -- Vivian Esq., Marino,
    near Swansea, South Wales....

    And now, my dear girl, I must set business aside. I am tired
    of the dull detail of things, and want to talk of love to you;
    and surely there can be no circumstances under which I can have
    more right. The theme was a cheerful and delightful one before
    we were married, but it is doubly so now. I now can speak, not
    of my own heart only, but of both our hearts. I now speak, not
    with any doubt of the state of your thoughts, but with the
    fullest conviction that they answer to my own. All that I can
    now say warm and animated to you, I know that you would say to
    me again. The excess of pleasure which I feel in knowing you
    mine is doubled by the consciousness that you feel equal joy in
    knowing me yours.

[Sidenote: FROM HUSBAND TO WIFE.]

                                        Marino: Sunday, July 28, 1822.

    MY DEARLY BELOVED WIFE,--I have just read your letter again,
    preparatory to my writing to you, that my thoughts might be
    still more elevated and quickened than before. I could almost
    rejoice at my absence from you, if it were only that it has
    produced such an earnest and warm mark of affection from you
    as that letter. Tears of joy and delight fell from my eyes on
    its perusal. I think it was last Sunday evening, about this
    time, that I wrote to you from London; and I again resort to
    this affectionate conversation with you, to tell you what has
    happened since the letter which I got franked from this place
    to you on Thursday I believe.

       *       *       *       *       *

    We have been working very hard here at the copper works, and
    with some success. Our days have gone on just as before. A walk
    before breakfast; then breakfast; then to the works till four
    or five o’clock, and then home to dress, and dinner. After
    dinner, tea and conversation. I have felt doubly at a loss
    to-day, being absent from both the meeting and you. When away
    from London before, I have had you with me, and we could read
    and talk and walk; to-day I have had no one to fill your place,
    so I will tell you how I have done. There are so many here, and
    their dinner so late and long, that I made up my mind to avoid
    it, though, if possible, without appearing singular. So, having
    remained in my room till breakfast time, we all breakfasted
    together, and soon after Mr. Phillips and myself took a walk
    out to the Mumbles Point, at the extremity of this side of
    the bay. There we sat down to admire the beautiful scenery
    around us, and, after we had viewed it long enough, returned
    slowly home. We stopped at a little village in our way, called
    Oystermouth, and dined at a small, neat, homely house about
    one o’clock. We then came back to Marino, and after a little
    while again went out--Mr. Phillips to a relation in the town,
    and myself for a walk on the sands and the edge of the bay. I
    took tea in a little cottage, and, returning home about seven
    o’clock, found them engaged at dinner, so came up to my own
    room, and shall not see them again to-night. I went down for a
    light just now, and heard them playing some sacred music in the
    drawing-room; they have all been to church to-day, and are what
    are called regular people.

    The trial at Hereford is put off for the present, but yet we
    shall not be able to be in town before the end of this week.
    Though I long to see you, I do not know when it will be;
    but this I know, that I am getting daily more anxious about
    you. Mr. Phillips wrote home to Mrs. Phillips from here even
    before I did--_i.e._ last Wednesday. This morning he received
    a letter from Mrs. Phillips (who is very well) desiring him
    to ask me for a copy of one of my letters to you, that he may
    learn to write love-letters of sufficient length. He laughs at
    the scolding, and says that it does not hurt at a distance....

    It seems to me so long since I left you that there must have
    been time for a great many things to have happened. I expect to
    see you with such joy when I come home that I shall hardly know
    what to do with myself. I hope you will be well and blooming,
    and animated and happy, when you see me. I do not know how we
    shall contrive to get away from here. We certainly shall not
    have concluded before Thursday evening, but I think we shall
    endeavour earnestly to leave this place on Friday night, in
    which case we shall get home late on Saturday night. If we
    cannot do that, as I should not like to be travelling all day
    on Sunday, we shall probably not leave until Sunday night; but
    I think the first plan will be adopted, and that you will not
    have time to answer this letter. I expect, nevertheless, an
    answer to my last letter--_i.e._ I expect that my dear wife
    will think of me again. Expect here means nothing more than
    I trust and have a full confidence that it will be so. My
    kind girl is so affectionate that she would not think a dozen
    letters too much for me if there were time to send them, which
    I am glad there is not.

    Give my love to our mothers as earnestly as you would your own,
    and also to Charlotte or John, or any such one that you may
    have with you. I have not written to Paternoster Row yet, but
    I am going to write now, so that I may be permitted to finish
    this letter here. I do not feel quite sure, indeed, that the
    permission to leave off is not as necessary from my own heart
    as from yours.

    With the utmost affection--with perhaps too much--I am, my dear
    wife, my Sarah, your devoted husband,

                                        M. FARADAY.


Faraday’s next scientific success was the liquefaction of chlorine
(see Chapter III., p. 93). This discovery, which created much interest
in the scientific world, was the occasion of a serious trouble with
Sir Humphry Davy; for doubtless Davy was annoyed that he had left such
a simple experiment to a mere assistant. Writing on the matter years
after, Faraday said:--

    When my paper was written, it was, according to a custom
    consequent upon our relative positions, submitted to Sir
    H. Davy (as were all my papers for the “Philosophical
    Transactions” up to a much later period), and he altered it as
    he thought fit. This practice was one of great kindness to me,
    for various grammatical mistakes and awkward expressions were
    from time to time thus removed, which might else have remained.

In point of fact, Davy on this occasion added a note (which was duly
printed) saying precisely how far he had any share in suggesting the
experiment, but in no wise traversing any of Faraday’s claims. Although
he thus acted generously to the latter, there can be no question
that he began to be seriously jealous of Faraday’s rising fame. The
matter was the more serious because some who did not have a nice
appreciation of the circumstances chose to rake up a charge which had
been raised two years before against Faraday by some of Dr. Wollaston’s
friends--in particular by Dr. Warburton--about the discovery of the
electro-magnetic rotations, a charge which Faraday’s straightforward
action and Wollaston’s frank satisfaction ought to have dissipated
for ever. And all this was doubly aggravating because Faraday was now
expecting to be proposed as a candidate for the Fellowship of the Royal
Society, of which Sir Humphry was President.

[Sidenote: PROPOSED FOR THE FELLOWSHIP.]

At that time, as now, the proposal paper or “certificate” of a
candidate for election must be presented, signed by a number of
influential Fellows. Faraday’s friend Phillips took in hand the
pleasant task of drawing up this certificate and of collecting
the necessary signatures. The rule then was that the certificate
so presented must be read out at ten successive meetings of the
Society; after which a ballot took place. Faraday’s certificate bears
twenty-nine names. The very first is that of Wollaston, and it is
followed by those of Children, Babington, Sir John Herschel, Babbage,
Phillips, Roget, and Sir James South.

On the 5th of May, 1823, Faraday wrote to Phillips:--

    A thousand thanks to you for your kindness--I am delighted with
    the names--Mr. Brande had told me of it before I got your note
    and thought it impossible to be better. I suppose you will not
    be in Grosvenor Street this Evening, so I will put this in the
    post.

    Our Best remembrances to Mrs. Phillips.

                                        Yours Ever,
                                              M. FARADAY.


The certificate was read for the first time on May 1st. The absence
of the names of Davy and Brande is accounted for by the one being
President and the other Secretary. Bence Jones gives the following
account of what followed:--

    That Sir H. Davy actively opposed Faraday’s election is no less
    certain than it is sad.

    Many years ago, Faraday gave a friend the following facts,
    which were written down immediately:--“Sir H. Davy told me I
    must take down my certificate. I replied that I had not put
    it up; that I could not take it down, as it was put up by my
    proposers. He then said I must get my proposers to take it
    down. I answered that I knew they would not do so. Then he
    said, I as President will take it down. I replied that I was
    sure Sir H. Davy would do what he thought was for the good of
    the Royal Society.”

    Faraday also said that one of his proposers told him that Sir
    H. Davy had walked for an hour round the courtyard of Somerset
    House, arguing that Faraday ought not to be elected. This was
    probably about May 30.

Faraday also made the following notes on the circumstance of the charge
made by Wollaston’s friends:--

    1823. _In relation to Davy’s opposition to my election at the
    Royal Society._

    Sir H. Davy angry, May 30.

    Phillips’ report through Mr. Children, June 5.

    Mr. Warburton called first time, June 5 (evening).

    I called on Dr. Wollaston, and he not in town, June 9.

    I called on Dr. Wollaston, and saw him, June 14.

    I called at Sir H. Davy’s, and he called on me, June 17.

On July 8 Dr. Warburton wrote that he was satisfied with Faraday’s
explanation, and added that he would tell his friends that “my
objections to you as a Fellow are and ought to be withdrawn, and that I
now wish to forward your election.”

Bence Jones adds:--

    On June 29, Sir H. Davy ends a note, “I am, dear Faraday, very
    sincerely your well wisher and friend.” So that outwardly the
    storm rapidly passed away; and when the ballot was taken, after
    the certificate had been read at ten meetings, there was only
    one black ball.

[Sidenote: FELLOWSHIP AND MAGNANIMITY.]

The election took place January 8, 1824.

Of this unfortunate misunderstanding,[11] Davy’s biographer, Dr.
Thorpe, writes:--

    The jealousy thus manifested by Davy is one of the most pitiful
    facts in his history. It was a sign of that moral weakness
    which was at the bottom of much of his unpopularity, and which
    revealed itself in various ways as his physical strength
    decayed....

Faraday allowed himself in after days no shade of resentment against
Davy; though he confessed rather sadly that after his election as
F.R.S. his relations with his former master were never the same as
before. If anyone recurred to the old scandal, he would fire with
indignation. Dumas in his “Éloge Historique” has given the following
anecdote:--

    Faraday never forgot what he owed to Davy. Visiting him at the
    family lunch, twenty years after the death of the latter, he
    noticed evidently that I responded with some coolness to the
    praises which the recollection of Davy’s great discoveries had
    evoked from him. He made no comment. But, after the meal, he
    simply took me down to the library of the Royal Institution,
    and stopping before the portrait of Davy he said: “He was a
    great man, wasn’t he?” Then, turning round, he added, “It was
    here[12] that he spoke to me for the first time.” I bowed. We
    went down to the laboratory. Faraday took out a note-book,
    opened it and pointed out with his finger the words written
    by Davy, at the very moment when by means of the battery he
    had just decomposed potash, and had seen the first globule of
    potassium ever isolated by the hand of man. Davy had traced
    with a feverish hand a circle which separates them from the
    rest of the page: the words, “Capital Experiment,” which
    he wrote below, cannot be read without emotion by any true
    chemist. I confessed myself conquered, and this time, without
    hesitating longer, I joined in the admiration of my good friend.

Dr. Thorpe in his life of Davy adds:--

    ... To the end of his days he [Faraday] regarded Davy as his
    true master, preserving to the last, in spite of his knowledge
    of the moral frailties of Davy’s nature, the respect and even
    reverence which is to be seen in his early lecture notes and in
    his letters to his friend Abbott.

In 1823 the Athenæum Club was started by J. Wilson Croker, Sir H. Davy,
Sir T. Lawrence, Sir F. Chantrey, and others, as a resort for literary
and scientific men. Faraday was made Club Secretary; but he found the
duties totally uncongenial, and in 1824 resigned the post to his friend
Magrath.

Faraday was advanced in 1825 to the position of Director of the
Laboratory of the Royal Institution, Brande remaining Professor of
Chemistry. One of the first acts of the new Director was to hold
evening meetings of the members in the laboratory, when experiments
were shown and some demonstration was given. There were three or four
of these informal gatherings that year. In the next year these Friday
evening meetings were held more systematically. There were seventeen
during the season, at six of which Faraday gave discourses (see p.
100). In 1827 there were nineteen, of which he delivered three. By this
time the gatherings were held in the theatre as at present, save that
ladies were only admitted at that date, and for many years, to the
upper gallery. He also originated the Christmas lectures to juveniles,
while continuing to give regular courses of morning lectures, as his
predecessors Young and Davy had done. His activity for the Royal
Institution was incessant.

[Sidenote: FEES FOR PROFESSIONAL WORK.]

Down to the year 1830 Faraday continued to undertake, at professional
fees, chemical analyses and expert work in the law-courts, and thereby
added considerably to the very slender emolument of his position;
but, finding this work to make increasing demands on his time, which
he could ill spare from the absorbing pursuit of original researches,
he decided to abandon a practice which would have made him rich, and
withdrew from expert practice. The following letter to Phillips was
written only a few weeks before this determination:--

    [_M. Faraday to Richard Phillips._]

                                        Royal Institution,
                                              June 21, 1831.

    MY DEAR PHILLIPS,--I have been trying hard to get time enough
    to write to you by post to-night, but without success; the
    bell has rung, and I am too late. However, I am resolved to
    be ready to-morrow. We have been very anxious and rather
    embarrassed in our minds about your anxiety to know how things
    were proceeding, and uncertain whether reference to them
    would be pleasant, and that has been the cause why I have
    not written to you, for I did not know what character your
    connexion with Badams had. I was a little the more embarrassed
    because of my acquaintance with Mr. Rickard and his family,
    and, of course with his brother-in-law, Dr. Urchell, of whom I
    have made numerous enquiries to know what Mr. Rickard intended
    doing at Birmingham. He (expressed a) hope it would be nothing
    unpleasant to you, but was not sure. Our only bit of comfort in
    the matter was on hearing from Daniell about you a little; he
    was here to-day, and glad to hear of you through me. But now
    that I may write, let me say that Mrs. Faraday has been very
    anxious with myself, and begs me earnestly to remember her to
    Mrs. Phillips. We have often wished we could have had you here
    for an hour or two, to break off what we supposed might be the
    train of thoughts at home.

    With regard to the five guineas, do not think of it for a
    moment. Whilst I supposed a mercantile concern wanted my
    opinion for its own interested uses, I saw no reason why it
    should not pay me; but it is altogether another matter when it
    becomes _your affair_. I do not think you would have wished
    _me_ to pay _you_ five guineas for anything you might have done
    personally for me. “Dog don’t eat dog,” as Sir E. Home said to
    me in a similar case. The affair is settled.

    I have no doubt I shall be amused and, as you speak of new
    facts, instructed by your letter to Dr. Reid, as I am by all
    your letters. Daniell says he thinks you are breaking a fly
    upon the wheel. You know I consider you as the Prince of
    Chemical critics.

    Pearsall has been working, as you know, on red manganese
    solutions. He has not proved, but he makes out a strong
    case for the opinion, that they owe their colour and other
    properties to manganesic acid. This paper will be in the next
    number of the Journal.

    With regard to the gramme, wine-pint, etc., etc., in the
    manipulation I had great trouble about them, for I could find
    no agreement, and at last resolved to take certain conclusions
    from Capt. Kater’s paper and the Act of Parliament, and
    calculate the rest. I think I took the data at page 67,
    paragraph 119, as the data, but am not sure, and cannot go over
    them again.

    My memory gets worse and worse daily. I will not, therefore,
    say I have not received your Pharmacopœia--that of 1824 is what
    I have at hand and use. I am not aware of any other. I have
    sent a paper to the R. S., but not chemical. It is on sound,
    etc., etc. If they print it, of course you will have a copy in
    due time.

                    I am, my dear Phillips,
                            Most faithfully and sincerely yours,
                                                  M. FARADAY.

    Is it right to ask what has become of Badams? I suppose he is,
    of course, a defaulter at the R. S.

[Sidenote: SACRIFICES FOR SCIENCE.]

This sacrifice for science was not small. He had made £1,000 in 1830
out of these professional occupations, and in 1831 would have made
more but for his own decision. In 1832 some Excise work that he had
retained brought him in £155 9s.; but in no subsequent year did it
bring in so much. He might easily have made £5,000 a year had he
chosen to cultivate the professional connection thus formed; and as he
continued, with little intermission, in activity till 1860, he might
have died a wealthy man. But he chose otherwise; and his first reward
came in the autumn of 1831, in the great discovery of magneto-electric
currents--the principle upon which all our modern dynamos and
transformers are based, the foundation of all the electric lighting and
electric transmission of power. From this work he went on to a research
on the identity of all the kinds of electricity, until then supposed
to be of separate sorts, and from this to electro-chemical work of the
very highest value. Of all these investigations some account will be
found in the chapters which follow.

But the immense body of patient scientific work thus done for the love
of science was not accomplished without sacrifices of a more than
pecuniary kind. He withdrew more and more from society, declined to
dine in company, ceased to give dinners, withdrew from all social and
philanthropic organisations; even withdrew from taking any part in the
management of any of the learned societies. The British Association for
the Advancement of Science was started in 1831. Faraday took no part
in that movement, and did not attend the inaugural meeting at York.
The next year, however, he attended the second meeting of that body at
Oxford. Here he “had the pleasure”--it is his own phrase--of making
an experiment on the great magnet in the University museum, drawing a
spark by induction in a coil of wire. This was a coil 220 feet long,
wound on a hollow cylinder of pasteboard, which had been used in the
classical experiments of the preceding year. He also showed that the
induced currents could heat a thin wire connected to the terminals
of this coil. These experiments, which were made in conjunction with
Mr. (afterwards Sir William Snow) Harris, Professor Daniell, and
Mr. Duncan, seem to have excited great attention at the time. The
theologians of Oxford appear to have been mightily distressed both by
the success of the spark experiment and by the welcome shown by the
University to the representatives of science. The following passage
from Pusey’s life[13] reveals the rampant clericalism which then and
for a score of years sought to put back the clock of civilisation.

    During the Long Vacation of 1832 Pusey had plenty of work on
    hand. The British Association had held its first meeting in
    Oxford during the month of June, and on the 21st the honorary
    degree of D.C.L. was bestowed on four of its distinguished
    members: Brewster, Faraday, Brown, and Dalton. Keble, who was
    now Professor of Poetry, was angry at the “temper and tone of
    the Oxford doctors”; they had “truckled sadly to the spirit of
    the times” in receiving “the hodge-podge of philosophers” as
    they did. Dr. L. Carpenter had assured Dr. Macbride that “the
    University had prolonged her existence for a hundred years by
    the kind reception he and his fellows had received.”

[Sidenote: THE HODGE-PODGE OF PHILOSOPHERS.]

It is not without significance, perhaps, that all the four men thus
contemptuously labelled by Keble as the “hodge-podge of philosophers”
were Dissenters. Brewster and Brown (the great botanist and discoverer
of the “Brownian” motion of particles) belonged to the Presbyterian
Church of Scotland, Dalton was a Member of the Society of Friends, and
Faraday a Sandemanian. Newman appears to have been equally discomposed
by the circumstance, for he got his friend Mr. Rose to write an
article--a long and weary diatribe--against the British Association,
which he inserted in the _British Critic_ for 1839. Its slanders,
assumptions, suppressions, and suggestions are in a very unworthy
temper.

Faraday’s devotion to the Royal Institution and its operations was
marvellous. He had already abandoned outside professional work. From
1838 he refused to see any callers except three times a week. His
extreme desire was to give himself uninterruptedly to research. His
friend A. de la Rive says:--

    Every morning Faraday went into his laboratory as the man of
    business goes to his office, and then tried by experiment the
    truth of the ideas which he had conceived overnight, as ready
    to give them up if experiment said _no_ as to follow out the
    consequences with rigorous logic if experiment answered _yes_.

He had in 1827 declined the appointment of Professor of Chemistry in
the University (afterwards called University College) of London, giving
as his reason the interests of the Royal Institution. He wrote:--

    I think it a matter of duty and gratitude on my part to do
    what I can for the good of the Royal Institution in the
    present attempt to establish it firmly. The Institution has
    been a source of knowledge and pleasure to me for the last
    fourteen years; and though it does not pay me in salary what
    I _now_ strive to do for it, yet I possess the kind feelings
    and goodwill of its authorities and members, and all the
    privileges it can grant or I require; and, moreover, I remember
    the protection it has afforded me during the past years of
    my scientific life. These circumstances, with the thorough
    conviction that it is a useful and valuable establishment, and
    the strong hopes that exertions will be followed with success,
    have decided me in giving at least two years more to it, in the
    belief that after that time it will proceed well, into whatever
    hands it may pass.

In 1829, however, he was asked to become lecturer on chemistry at the
Royal Academy at Woolwich. As this involved only twenty lectures a year
he agreed, the salary being fixed at £200 a year. These lectures were
continued until 1849.

[Sidenote: TRINITY HOUSE APPOINTMENT.]

In 1836 the whole course of his scientific work was changed by his
appointment as scientific adviser to Trinity House, the body which has
official charge of the lighthouse service in Great Britain. To the
Deputy-master he wrote:--

    I consider your letter to me as a great compliment, and should
    view the appointment at the Trinity House, which you propose,
    in the same light; but I may not accept even honours without
    due consideration.

    In the first place, my time is of great value to me; and if
    the appointment you speak of involved anything like periodical
    routine attendances, I do not think I could accept it. But
    if it meant that in consultation, in the examination of
    proposed plans and experiments, in trials, etc., made as
    my convenience would allow, and with an honest sense of a
    duty to be performed, then I think it would consist with my
    present engagements. You have left the title and the sum in
    pencil. These I look at mainly as regards the character of the
    appointment; you will believe me to be sincere in this when you
    remember my indifference to your proposition as a matter of
    interest, though _not as a matter of kindness_.

    In consequence of the goodwill and confidence of all around me,
    I can at any moment convert my time into money, but I do not
    require more of the latter than is sufficient for necessary
    purposes. The sum, therefore, of £200 is quite enough in
    itself, but not if it is to be the indicator of the character
    of the appointment; but I think you do not view it so, and
    that you and I understand each other in that respect; and
    your letter confirms me in that opinion. The position which I
    presume you would wish me to hold is analogous to that of a
    standing counsel.

    As to the title, it might be what you pleased almost. Chemical
    adviser is too narrow, for you would find me venturing into
    parts of the philosophy of light not chemical. Scientific
    adviser you may think too broad (or in me too presumptuous);
    and so it would be, if by it was understood all science.

He held the post of scientific adviser for nearly thirty years. The
records of his work are to be found in nineteen large portfolios full
of manuscripts, all indexed with that minute and scrupulous attention
to order and method which characterised all his work.

He also held nominally the post of scientific adviser to the Admiralty,
at a salary of £200 a year. But this salary he never drew. Once the
officials of the Admiralty requested his opinion upon a printed
advertising pamphlet of somebody’s patent disinfecting powder and
anti-miasma lamp. Faraday returned it, with a quietly indignant protest
that it was not such a document as he could be expected to give an
opinion upon.

Faraday’s hope, expressed in 1827, that in two years the Royal
Institution might be restored to a financially sound position, was
not realised. He worked with the most scrupulous economy, noting down
every detail of expenditure even in farthings. “We were living on
the parings of our own skin,” he once told the managers. In 1832 the
financial question became acute. At the end of that year a committee of
investigation reported as follows:--

    The Committee are certainly of opinion that no reduction can be
    made in Mr. Faraday’s salary--£100 per annum, house, coals, and
    candles; and beg to express their regret that the circumstances
    of the Institution are not such as to justify their proposing
    such an increase of it as the variety of duties which Mr.
    Faraday has to perform, and the zeal and ability with which he
    performs them, appear to merit.

[Sidenote: A HUNDRED A YEAR, AND TWO ROOMS.]

A hundred a year, the use of two rooms, and coals! Such was the stipend
of the man who had just before been made D.C.L. of Oxford, and had
received from the Royal Society the highest award it can bestow--the
Copley Medal! True, he made £200 by the Woolwich lectures; but he had a
wife to maintain, his aged mother was entirely dependent upon him, and
there were many calls upon his private exercise of charity.

About the year 1835 it was the intention of Sir Robert Peel to
confer upon him a pension from the Civil List, but he went out of
office before this could be arranged, and Lord Melbourne became
Prime Minister. Sir James South had in March written to Lord Ashley,
afterwards the well-known Earl of Shaftesbury, asking him to place a
little historiette of Faraday in Sir Robert Peel’s hands. The said
historiette[14] contained an account of Faraday’s early career and
a description of the electrical machine which he had constructed as
a lad. “Now that his pecuniary circumstances,” it went on, “were
improved, he sent his younger sister to boarding-school, but to enable
him to defray the expense, to deprive himself of dinner every other day
was absolutely indispensable.” Peel expressed to Ashley lively regret
at not having received the historiette earlier when he was still in
office. To Ashley, later, he wrote the following hitherto unpublished
letter:--

                                        Drayton Manor,
                                            May 3, 1835.

    MY DEAR ASHLEY,--You do me but justice in entertaining the
    belief that had I remained in office one of my earliest
    recommendations to his Majesty would have been to grant a
    pension to Mr. Faraday, on the same principles precisely upon
    which one was granted to Mr. Airy. If there had been the means,
    I would have made the offer before I left office.

    I was quite aware of Mr. Faraday’s high eminence as a man of
    science, and the valuable practical service he has rendered
    to the public in that capacity; but I was to blame in not
    having ascertained whether his pecuniary circumstances made an
    addition to his income an object to him.

    I am sure no man living has a better claim to such a
    consideration from the State than he has, and I trust the
    principle I acted on with regard to the award of civil
    pensions will not only remove away impediments of delicacy
    and independent feeling from the acceptance of them, but will
    add a higher value to the grant of a pension as an honourable
    distinction than any that it could derive from its pecuniary
    amount.

                                        Ever, my dear Ashley,
                                            Most faithfully yours,
                                                          ROBERT PEEL.


[Sidenote: LORD MELBOURNE’S PARTICIPLE.]

Sir James South still endeavoured to bring about the grant thus
deferred, and wrote to the Hon. Caroline Fox, asking her to put the
historiette of Faraday in the hands of Lord Holland, for him to lay
before Melbourne. Faraday at first demurred to Sir James South’s
action, but on the advice of his father-in-law, Barnard, withdrew his
demurrer. Later in the year he was asked to wait on Lord Melbourne at
the Treasury. He has left a diary of the events of the day, October
26th. According to these notes it appears that Faraday first had
a long talk with Melbourne’s secretary, Mr. Young, about his first
demurring on religious grounds to accept the pension, about his
objection to savings’ banks, and the laying-up of wealth. Later in
the day he had a short interview with the First Lord of the Treasury,
when Lord Melbourne, utterly mistaking the nature of the man before
him, inveighed roundly upon the whole system of giving pensions to
scientific and literary persons, which he described as a piece of
humbug. He prefixed the word “humbug” with a participle which Faraday’s
notes describe as “theological.” Faraday, with an instant flash of
indignation, bowed and withdrew. The same evening he left his card and
the following note at the Treasury:--

    _To the Right Hon. Lord Viscount Melbourne, First Lord of the
    Treasury._

                                        October 26.

    MY LORD,--The conversation with which your Lordship honoured
    me this afternoon, including, as it did, your Lordship’s
    opinion of the general character of the pensions given of late
    to scientific persons, induces me respectfully to decline the
    favour which I believe your Lordship intends for me; for I
    feel that I could not, with satisfaction to myself, accept at
    your Lordship’s hands that which, though it has the form of
    approbation, is of the character which your Lordship so pithily
    applied to it.

Faraday’s diary says:--

    Did not like it much, and, on the whole, regret that friends
    should have placed me in the situation in which I found myself.
    Lord Melbourne said that “he thought there had been a great
    deal of humbug in the whole affair. He did not mean my affair,
    of course, but that of the pensions altogether.”... I begged
    him to understand that I had known nothing of the matter until
    far advanced, and, though grateful to those friends who had
    urged it forward, wished him to feel at perfect liberty in the
    affair as far as I was concerned.... In the evening I wrote and
    left a letter. I left it myself at ten o’clock at night, being
    anxious that Lord Melbourne should have it before anything
    further was done in the affair.

[Sidenote: MICHAEL’S PENSION.]

However, the matter did not end here. Faraday’s friends were indignant.
A caustic, and probably exaggerated, account--for which Faraday
disclaimed all responsibility--of the interview appeared in _Fraser’s
Magazine_, and was copied into _The Times_ of November 28th, with the
result that, had it not been for the personal intervention of the King,
the pension might have been refused. The storm, however, passed away,
and the pension of £300 per annum was granted on December 24th. Years
afterwards, writing to Mr. B. Bell, Faraday said, “Lord Melbourne
behaved very handsomely in the matter.”

In _Fraser’s Magazine_ for February, 1836 (vol. xiii., p. 224), is
a portrait of Faraday by Maclise, accompanied by a very amusing
biographical notice by Dr. Maginn. The picture represents Faraday
lecturing, and surrounded by his apparatus. The article begins thus:--

    Here you have him in his glory--not that his position was
    _inglorious_ when he stood before Melbourne, then decorated
    with a blue velvet travelling cap, and lounging with one
    leg over the chair of Canning!--and distinctly gave that
    illustrious despiser of “humbug” to understand that he had
    mistaken his lad. No! but here you have him as he first
    flashed upon the intelligence of mankind the condensation of
    the gases, or the identity of the five electricities.

After a lively summary of his career, and the jocular suggestion that,
as the successor of Sir Humphry Davy, Far-a-day must be near-a-knight
the article continues:--

    The future Baronet is a very good little fellow ... playing a
    fair fork over a leg of mutton, and devoid of any reluctance
    to partake an old friend’s third bottle. We know of few things
    more agreeable than a cigar and a bowl of punch (which he mixes
    admirably) in the society of the unpretending ex-bookbinder....

    Well, although Young got Broderip to write a sort of defence of
    his master, and “Justice B----”--_mirabile dictu!_--got Hook
    to print it in the _John Bull_, the current of public feeling
    could not be stopped: REGINA spoke out--WILLIAM REX, as in duty
    bound, followed--Melbourne apologised--and “Michael’s pension,
    Michael’s pension” is all right.

In one of his note-books of this period is found the following entry:--

                                        15 January, 1834.

    Within the last week have observed twice that a slight
    obscurity of the sight of my left eye has happened. It occurred
    on reading the letters of a book held about fourteen inches
    from the eye, being obscured as by a fog over a space about
    half an inch in diameter. This space was a little to the right
    and below the axes of the eye. Looking for the effect now and
    other times, I cannot perceive it. I note this down that I may
    hereafter trace the progress of the effect if it increases or
    becomes more common.

Happily, the trouble did not recur; but the entry is characteristic
of the habits of accuracy of the man. Loss of memory, unfortunately,
early set in. There is actually a hint of this in the first of
his letters to Abbott (p. 7), and references to the trouble and to
dizziness in the head recur perpetually in his correspondence. Whenever
these brain-troubles threatened, he was compelled to drop all work
and seek rest and change of scene. He often ran down to Brighton,
which he thought, however, a poor place. He constructed for himself a
velocipede[15] on which to take exercise. Two or three times he went to
Switzerland for a longer holiday, usually accompanied by his wife and
her brother, George Barnard.

“Physically,” says Tyndall, “Faraday was below the middle size, well
set, active, and with extraordinary animation of countenance. His head
from forehead to back was so long that he had usually to bespeak his
hats.” In youth his hair was brown, curling naturally; later in life it
approached to white, and he always parted it down the middle. His voice
was pleasant, his laugh was hearty, his manners when with young people,
or when excited by success in the laboratory, were gay to boyishness.
Indeed, until the end of the active period of his life he never lost
the capacity for boyish delight, or for unbending in fun after the
stress of severe labour.




CHAPTER III.

SCIENTIFIC RESEARCHES: FIRST PERIOD.


From first to last the original scientific researches of Faraday extend
over a period of forty-four years, beginning with an analysis of
caustic lime, published in the _Quarterly Journal of Science_ in 1816,
and ending with his last unfinished researches of 1860 to 1862, on
the possible existence of new relations between magnetism and gravity
and between magnetism and light. The mere list of their titles fills
several pages in the catalogue of scientific papers published by the
Royal Society.

For convenience of description, these forty-four years may be divided
into three periods: the first lasting from 1816 to 1830, a period of
miscellaneous and in some respects preliminary activity; the second
from 1831 to the end of 1839, the period of the classical experimental
researches in electricity down to the time when they were temporarily
suspended by the serious state of his health; the third from 1844, when
he was able to resume work, down to 1860, a period which includes the
completion of the experimental researches on electricity, the discovery
of the relations between light and magnetism, and that of diamagnetism.

[Sidenote: RESEARCHES BEGINNING.]

Faraday’s first research was an analysis for Sir Humphry Davy of a
specimen of caustic lime which had been sent to him by the Duchess
of Montrose from Tuscany. The _Quarterly Journal of Science_, in
which it appeared, was a precursor of the _Proceedings of the Royal
Institution_, and was indeed edited by Professor W. F. Brande. Faraday
frequently wrote for it during these years, and took editorial
charge of it on more than one occasion during Brande’s holidays. The
paper on caustic lime was reprinted by Faraday in the volume of his
“Experimental Researches on Chemistry and Physics,” prefaced by the
following note:--

    I reprint this paper at full length; it was the beginning
    of my communications to the public, and in its results very
    important to me. Sir Humphry Davy gave me the analysis to
    make as a first attempt in chemistry, at a time when my fear
    was greater than my confidence, and both far greater than
    my knowledge; at a time also when I had no thought of ever
    writing an original paper on science. The addition of his own
    comments, and the publication of the paper, encouraged me to
    go on making, from time to time, other slight communications,
    some of which appear in this volume. Their transference from
    the _Quarterly_ into other journals increased my boldness,
    and now that forty years have elapsed, and I can look back on
    what successive communications have led to, I still hope, much
    as their character has changed, that I have not either now or
    forty years ago been too bold.

For the next two or three years Faraday was very closely occupied in
the duties of assisting Sir Humphry Davy in his researches, and in
helping to prepare the lectures for both Davy and Brande. Yet he
found time still to work on his own account. In 1817 he had six papers
and notes in the _Quarterly Journal of Science_, including one on the
escape of gases through capillary tubes, and others on wire-gauze
safety lamps and Davy’s experiments on flame. In 1818 he had eleven
papers in the _Journal_; the most important being on the production of
sound in tubes by flames, while another was on the combustion of the
diamond. In 1819 he had nineteen papers in the _Quarterly Journal_,
chiefly of a chemical nature. These related to boracic acid, the
composition of steels, the separation of manganese from iron, and on
the supposed new metal, “Sirium” or “Vestium,” which he showed to be
only a mixture of iron and sulphur with nickel, cobalt, and other
metals.

[Sidenote: OERSTED’S DISCOVERY.]

The year 1820 was marked in the annals of science by the discovery,
by Oersted of Copenhagen, of the prime fact of electromagnetism, the
deflexion which is produced upon a magnetic needle by an electric
current that passes either under or over the needle. Often had it been
suspected that there must be some connection between the phenomena
of electricity and those of magnetism. The similarities between the
attractions and repulsions caused by electrified bodies, and those
due to the magnet when acting on iron, had constantly suggested the
possibility that there was some real connection. But, as had been
pointed out centuries before by St. Augustine, while the rubbed
amber will attract any substance if only small or light enough,
being indifferent to its material, the magnet will only attract iron
or compounds of iron, and is totally inoperative[16] on all other
substances. Again, while it had been noticed that in houses which had
been struck by lightning knives, needles, and other steel objects near
the path of the electric flash had become magnetised, no one had been
able, by using the most powerful electric machines, to repeat with
certainty the magnetisation of needles. In vain they had tried to
magnetise knives and wires by sending sparks through them. Sometimes
they showed a trace of magnetism, sometimes none. And in the cases
where some slight magnetisation resulted, the polarity could not be
depended upon. Van Swinden had written a whole treatise in two volumes
on the analogies between electricity and magnetism, but left the real
relation between the two more obscure than ever. After the invention,
in 1800, of the voltaic pile, which for the first time provided a
means of generating a steady flow or current of electricity, several
experimenters, including Oersted himself, had again essayed to discover
the long-suspected connection, but without success. Oersted was
notoriously a poor experimenter, though a man of great philosophical
genius. Having in 1820 a more powerful voltaic battery in operation
than previously, he repeated[17] the operation of bringing near to the
compass needle the copper wire that conveyed the current; and, laying
it parallel to the needle’s direction, and over or under it, found that
the needle tended to turn into a direction at right angles to the line
of the current, the sense of the deviation depending upon the direction
of flow of the current, and also on the position of the wire as to
whether it were above or below the needle. A current flowing from south
to north over the needle caused the north-pointing end of the needle to
be deflected westwards. If the wire were vertical, so that the current
flowed downwards, and a compass needle was brought near the wire on the
south side, therefore tending under the earth’s directive influence to
point northwards toward the wire, it was observed that the effect of
the current flowing in the wire was to cause the north-pointing end of
the needle to turn westwards. Or, reversing the flow of current, the
effect on the needle was reversed; it now tended eastwards. All these
things Oersted summed up in the phrase that “the electric conflict acts
in a revolving manner” around the wire.[18] In modern phraseology the
whole of the actions are explained if one can conceive that the effect
of the electric flow in the wire is to tend to make the north pole of
a magnet revolve in one sense around the wire, whilst it also tends
to make the south pole of the magnet revolve around the wire in the
other sense. The nett result in most cases is that the magnetic needle
tends to set itself square across the line of the current. Oersted
himself was not too clear in his explanations, and seems, in his later
papers, to have lost sight of the circular motion amidst repulsions and
attractions.

This discovery, which showed what was the geometrical relation between
the magnet and the current, also showed why the earlier attempts had
failed. It was requisite that the electricity should be in a state
of steady flow; neither at rest as in the experiments with electric
charges, nor yet in capricious or oscillatory rush as in those with
spark-discharges. Faraday, adverting a quarter of a century later to
Oersted’s discovery, said: “It burst open the gates of a domain in
science, dark till then, and filled it with a flood of light.”

The very day that Oersted’s memoir was published in England, Davy
brought a copy down into the laboratory of the Royal Institution, and
he and Faraday at once set to work to repeat the experiments and verify
the facts.

It is a matter of history how, on the publication of Oersted’s
discovery, Ampère leaped forward to generalise on electromagnetic
actions, and discovered the mutual actions that may exist between two
currents, or rather between two conducting wires that carry currents.
They are found to experience mutual mechanical forces urging them into
parallel proximity. Biot and Laplace added to these investigations,
as also did Arago. Davy discovered that the naked copper wire, while
carrying a current, could attract iron filings to itself--not end-ways
in adherent tufts, as the pole of a magnet does, but laterally, each
filing or chainlet of filings tending to set itself tangentially at
right angles to the axis of the wire.

[Sidenote: A PARADOXICAL PHENOMENON.]

This curious right-angled relation between electric flow and magnetic
force came as a complete paradox or puzzle to the scientific world.
It had taken centuries to throw off the strange unmechanical ideas of
force which had dominated the older astronomy. The epicyclic motions
of the planets postulated by the Ptolemaic system were in no way to be
accounted for upon mechanical principles. Kepler’s laws of planetary
motion were merely empirical, embodying the results of observation,
until Newton’s discovery of the laws of circular motion and of the
principle of universal gravitation placed the planetary theory on
a rational basis. Newton’s laws required that forces should act in
straight lines, and that to every action there should be an equal and
opposite reaction. If A attracted B, then B attracted A with an equal
force, and the mutual force must be in the line drawn from A to B. The
discovery by Oersted that the magnet pole was urged by the electric
wire in a direction _transverse_ to the line joining them, appeared at
first sight to contravene the ideas of force so thoroughly established
by Newton. How could this transversality be explained? Some sought to
explain the effect by considering the conducting wire to operate as if
made up of a number of short magnets set transversely across the wire,
all their north poles being set towards the right, and all their south
poles towards the left. Ampère took the alternative view that the
magnet might be regarded as equivalent to a number of electric currents
circulating transversely around the core as an axis. In neither case
was the explanation complete.

[Sidenote: TWO YEARS WASTED.]

Faraday’s scientific activities in the year 1820 were very marked. New
researches on steel had been going on for some months. It had been
hoped that by alloying iron with some other metals, such as silver,
platinum, or nickel, a non-rusting alloy might be found. This idea
took its rise from the erroneous notion that meteoric iron, which
is richly alloyed with nickel, does not rust. Faraday found nickel
steel to be more readily oxidised, not less, than ordinary steel. The
platinum steel was also a failure. Silver steel was of more interest,
though it was found impossible to incorporate in the alloy more than
a small percentage of silver. Nevertheless, silver steel was used
for some time by a Sheffield firm for manufacture of fenders. The
alloys of iron with platinum, iridium, and rhodium were also of no
great use. But the research demonstrated the surprising effects which
minute quantities of other metals may have upon the quality of steel.
Occasionally in later life Faraday would present one of his friends
with a razor made from his own special steel. A paper on the use of
alloys of steel in surgical instrument making was published in the
_Quarterly Journal_ in collaboration with Mr. Stodart. Faraday also
read his first paper before the Royal Society on two new compounds
of chlorine and carbon, and on a new compound of iodine, carbon,
and hydrogen. He also succeeded in making artificial plumbago from
charcoal. In writing to his friend Professor G. de la Rive, he gives
a long and chatty abstract of his researches on the alloys of steel.
They appear to have originated in some analyses of wootz or Indian
steel, a material which, when etched with acid, shows a beautifully
damascened or reticulated surface. This effect Faraday never found with
pure steel, but imitated it successfully with a steel alloyed with “the
metal of alumine,” an element which down to that time had not been
isolated. He then describes the rhodium, silver, and nickel steels, and
mentions incidentally how he has been surprised to discover that he
can volatilise silver, and that he cannot reduce the metal titanium.
He is doubtful whether this metal “ever has been reduced at all in the
pure state.” [It can now be readily reduced either in the electric arc
or by the use of metallic aluminium.] He winds up the letter with the
words: “Pray pity us that, after two years’ experiments, we have got no
further; but I am sure, if you knew the labour of the experiments, you
would applaud us for our perseverance at least.”

In 1821, the year of his marriage, came the first of the important
scientific discoveries which brought him international fame. This
was the discovery of the electromagnetic rotations. It appears that
Oersted’s brilliant flash of insight that the “electric conflict acts
in a revolving manner” upon the pole of the neighbouring compass needle
had been lost sight of in the discussions which followed, and to
which allusion has been made above. All the world was thinking about
attractions and repulsions. Two men, however, seem to have gone a
little further in their ideas. Dr. Wollaston had suggested that there
ought to be a tendency, when a magnet pole was presented towards a
straight conducting wire carrying a current, for that conducting wire
to revolve around its own axis. This effect--though in recent years
it has been observed by Mr. George Gore--he unsuccessfully tried to
observe by experiments. He came in April, 1821, to the laboratory
of the Royal Institution to make an experiment, but without result.
Faraday, at the request of his friend Phillips, who was editor of the
_Annals of Philosophy_, wrote for that magazine in July, August, and
September a historical sketch of electromagnetism down to date. This
was one of the very few of Faraday’s writings that was anonymous. It
was simply signed “M.” This is in vol. iii. p. 107. On p. 117 the
editor says: “To the historical sketch of electromagnetism with which I
have been favoured by my anonymous correspondent, I shall add a sketch
of the discoveries that have been made by Mr. Faraday of the Royal
Institution.” In the course of this work Faraday repeated for his own
satisfaction almost all the experiments that he described. This led him
to discover that a wire, included in the circuit, but mounted so as to
hang with its lower end in a pool of quicksilver, could rotate around
the pole of a magnet; and conversely that if the wire were fixed and
the pole of the magnet free to move, the latter would rotate around the
former. “I did not realise,” he wrote, “Dr. Wollaston’s expectation
of the rotation of the electromagnetic wire around its axis.” As was
so often his custom, he had no sooner finished the research for
publication than he dashed off a brief summary of it in a letter to one
of his friends. On this occasion it was Professor G. de la Rive, of
Geneva, who was the recipient of his confidences. On September 12 he
wrote:--

[Sidenote: LETTER TO DE LA RIVE.]

    I am much flattered and encouraged to go on by your good
    opinion of what little things I have been able to do in
    science, and especially as regards the chlorides of carbon.

       *       *       *       *       *

    You partly reproach us here with not sufficiently esteeming
    Ampère’s experiments on electromagnetism. Allow me to extenuate
    your opinion a little on this point. With regard to the
    experiments, I hope and trust that due weight is allowed to
    them; but these you know are few, and theory makes up the great
    part of what M. Ampère has published, and theory in a great
    many points unsupported by experiments when they ought to have
    been adduced. At the same time, M. Ampère’s experiments are
    excellent, and his theory ingenious; and, for myself, I had
    thought very little about it before your letter came, simply
    because, being naturally sceptical on philosophical theories, I
    thought there was a great want of experimental evidence. Since
    then, however, I have engaged on the subject, and have a paper
    in our “Institution Journal,” which will appear in a week or
    two, and that will, as it contains experiment, be immediately
    applied by M. Ampère in support of his theory, much more
    decidedly than it is by myself. I intend to enclose a copy of
    it to you with the other, and only want the means of sending it.

    I find all the usual attractions and repulsions of the magnetic
    needle by the conjunctive wire are deceptions, the motions
    being not attractions or repulsions, nor the result of any
    attractive or repulsive forces, but the result of a force in
    the wire, which instead of bringing the pole of the needle
    nearer to, or further from the wire, endeavours to make it
    move round it in a never ending circle and motion whilst the
    battery remains in action. I have succeeded not only in showing
    the existence of this motion theoretically, but experimentally,
    and have been able to make the wire revolve round a magnetic
    pole, or a magnetic pole round the wire, at pleasure. The law
    of revolution, and to which all the other motions of the needle
    and wire are reducible, is simple and beautiful.

    Conceive a portion of connecting wire north and south, the
    north end being attached to the positive pole of a battery, the
    south to the negative. A north magnetic pole would then pass
    round it continually in the apparent direction of the sun, from
    east to west above, from west to east below.

    Reverse the connections with the battery, and the motion of the
    pole is reversed; or if the south pole be made to revolve, the
    motions will be in the opposite directions, as with the north
    pole.

    If the wire be made to revolve round the pole, the motions are
    according to those mentioned. In the apparatus I used there
    were but two plates, and the directions of the motions were of
    course[19] the reverse of those with a battery of several pairs
    of plates, and which are given above. Now I have been able,
    experimentally, to trace this motion into its various forms as
    exhibited by Ampère’s, Nelice’s, &c., and in all cases to show
    that the attractions and repulsions are only appearances due
    to this circulation of the pole, to show that dissimilar poles
    repel as well as attract, and that similar poles attract as
    well as repel, and to make, I think, the analogy between the
    helix and common bar magnet far stronger than before. But yet I
    am by no means decided that there are currents of electricity
    in the common magnet.

    I have no doubt that electricity puts the circles of the
    helix into the same state as those circles are in, that may
    be conceived in the bar magnet, but I am not certain that
    this state is directly dependant on the electricity, or that
    it cannot be produced by other agencies; and therefore, until
    the presence of electrical currents be proved in the magnet by
    other than magnetical effects, I shall remain in doubt about
    Ampère’s theory.

       *       *       *       *       *

    Wishing you all health and happiness, and waiting for news from
    you,

    I am, my dear Sir, your very obliged and grateful

                                        M. FARADAY.


The reference at the beginning of this letter to the chlorides of
carbon has to do with his discovery communicated to the Royal Society.
Later in the year, a joint paper on another compound of carbon and
chlorine, by himself and his friend Richard Phillips, was sent in. Both
were printed together in the _Philosophical Transactions_ of 1821.

[Sidenote: LEAVES FROM THE NOTE-BOOK.]

The following is an extract from Faraday’s laboratory book relating to
the discovery. The account is incomplete, a leaf having been torn out:--

                                        1821, Sept. 3.

    The effort of the wire is always to pass off at a right angle
    from the pole, indeed to go in a circle round it, so when
    either pole was brought up to the wire perpendicular to it and
    to the radius of the circle it described, there was neither
    attraction nor repulsion, but the moment the pole varied in the
    slightest manner either in or out, the wire moved one way or
    the other.

    The poles of the magnet act on the bent wire in all positions
    and not in the direction _only_ of any axis of the magnet, so
    that the current can hardly be cylindrical or arranged round
    the axis of a cylinder?

    From the motion above a north magnet pole in the centre of one
    of the circles should make the wire continually turn round.
    Arranged a magnet needle in a glass tube with mercury about it,
    and by a cork, water, &c., supported a connecting wire so that
    the upper end should go into the silver cup and its mercury,
    and the lower move in a channel of mercury round the pole of
    the needle. The battery arranged with the wire as before. In
    this way got the revolution of the wire round the pole of the
    magnet. The direction was as follow, looking from above down:--

    [Illustration: FIG. 2. (FACSIMILE OF ORIGINAL SKETCH.)]

    Very satisfactory, but make more sensible apparatus.

                                        Tuesday, Sept. 4.

    Apparatus for revolution of wire and magnet. A deep basin with
    bit of wax at bottom and then filled with mercury. A magnet
    stuck upright in wax so that pole just above the surface of
    mercury. Then piece of wire floated by cork at lower end
    dipping into merc^y and above into silver cup as before:--

    [Illustration: FIG. 3. (FACSIMILE OF ORIGINAL SKETCH.)]

The research on the electromagnetic rotations, which was published in
the _Quarterly Journal of Science_ for October, 1821 (and reprinted in
the second volume of the “Experimental Researches in Electricity”), was
the occasion of a very serious misunderstanding with Dr. Wollaston and
his friends, which at one time threatened to cause Faraday’s exclusion
from the Royal Society. Faraday’s prompt and frank action in appealing
to Dr. Wollaston saved him in a very unpleasant crisis; and the latter
came three or four times to the laboratory to witness the experiments.
On Christmas Day of the same year, Faraday succeeded in making a wire
through which an electric current is passing move under the influence
of the earth’s magnetism alone. His brother-in-law, George Barnard, who
was in the laboratory at the time, wrote:--“All at once he exclaimed,
‘Do you see, do you see, do you see, George?’ as the wire began to
revolve. One end I recollect was in the cup of quicksilver, the other
attached above to the centre. I shall never forget the enthusiasm
expressed in his face and the sparkling in his eyes!”

[Sidenote: SCENES IN THE LABORATORY.]

In 1822 little was added to Faraday’s scientific work. He had a
joint paper with Stodart on steel before the Royal Society, and
in the _Quarterly Journal_ two short chemical papers and four on
electromagnetical motions and magnetism. He had long kept a commonplace
book in which he entered notes and queries as well as extracts from
books and journals; but this year he began a fresh manuscript volume,
into which he transferred many of the queries and suggestions of
his own originating. This volume he called “Chemical Notes, Hints,
Suggestions, and Objects of Pursuit.” It contains many of the germs of
his own future discoveries, as the following examples show:--

    Convert magnetism into electricity.

    Do pith balls diverge by disturbance of electricities in
    consequence of induction or not?

    General effects of compression, either in condensing gases,
    or producing solutions, or even giving combinations at low
    temperatures.

    Light through gold leaf on to zine or most oxidable metals,
    these being poles--or on magnetic bars.

    Transparency of metals. Sun’s light through gold leaf. Two gold
    leaves made poles--light passed through one to the other.

Whenever any query found an answer, he drew his pen through it and
added the date. In front of the book--probably at some later time--he
wrote these words:--

    I already owe much to these notes, and think such a collection
    worth the making by every scientific man. I am sure none would
    think the trouble lost after a year’s experience.

A striking example had already occurred of similar suggestive notes in
the optical queries of Sir Isaac Newton.

In another manuscript notebook occur the following entries under date
of September 10, 1821:--

    2 similar poles though they repell at most distances attract at
    very small distances and adhere. Query why....

    Could not magnetise a plate of steel so as to resemble flat
    spiral. Either the magnetism would be very weak and irregular
    or there would be none at all.

These are interesting as showing how Faraday was educating himself
by continual experiment. The explanation of each of these paradoxes
has long passed into the commonplace of physics; but they would still
puzzle many who have learned their science bookishly at second-hand.

It will be noted that amongst the entries cited above there are two of
absolutely capital importance, one foreshadowing the great discovery
of magneto-electric induction, the other indicating how the existence
of electro-optical relations was shaping itself as a possibility in
Faraday’s mind. An entry in his laboratory book of September 10 is of
great interest:--

    Polarised a ray of lamp-light by reflection, and endeavoured to
    ascertain whether any depolarising action [is] exerted on it by
    water placed between the poles of a voltaic battery in a glass
    cistern; one Wollaston’s trough used; the fluids decomposed
    were pure water, weak solution of sulphate of soda, and strong
    sulphuric acid: none of them had any effect on the polarised
    light, either when out of or in the voltaic circuit, so that
    no particular arrangement of particles could be ascertained in
    this way.

[Sidenote: AN UNSUCCESSFUL EXPERIMENT.]

It may be added that no such optical effect of electrolytic conduction
as that here looked for has yet been discovered. The experiment,
unsuccessful at that day, remains still an unsuccessful one. A singular
interest attaches to it, however, and it was repeated several times by
Faraday in subsequent years, in hope of some results.

In 1823 Faraday read two papers to the Royal Society, one on Liquid
Chlorine, the other on the Condensation of several Gases into Liquids.
No sooner was the work completed than he dashed off a letter to De la
Rive to tell him what he had accomplished. Under date March 24, 1823,
he writes:--

    I have been at work lately, and obtained results which I
    hope you will approve of. I have been interrupted twice in
    the course of experiments by explosions, both in the course
    of eight days--one burnt my eyes, the other cut them; but
    fortunately escaped with slight injury only in both cases, and
    am now nearly well. During the winter I took the opportunity
    of examining the hydrate of chlorine, and analysing it; the
    results, which are not very important, will appear in the
    next number of the _Quarterly Journal_, over which I have no
    influence. Sir H. Davy, on seeing my paper, suggested to me to
    work with it under pressure, and see what would happen by heat,
    &c. Accordingly I enclosed it in a glass tube hermetically
    sealed, heated it, obtained a change in the substance, and
    a separation into two different fluids; and upon further
    examination I found that the chlorine and water had separated
    from each other, and the chlorine gas, not being able to
    escape, had condensed into the liquid form. To prove that it
    contained no water, I dried some chlorine gas, introduced it
    into a long tube, condensed it, and then cooled the tube, and
    again obtained fluid chlorine. Hence what is called chlorine
    gas is the vapour of a fluid....

       *       *       *       *       *

    I expect to be able to reduce many other gases to the liquid
    form, and promise myself the pleasure of writing you about
    them. I hope you will honour me with a letter soon.

    I am, dear Sir, very faithfully, your obedient servant,

                                        M. FARADAY.


[Sidenote: CHLORINE LIQUEFIED.]

The work of liquefying the gases had been taken up by Faraday
during his hours of liberty from other duties. It was probably his
characteristic dislike to “doubtful knowledge” which prompted him to
re-examine a substance which had at one time been regarded as chlorine
in a solid state, but which Davy in 1810 had demonstrated to be a
hydrate of that element. The first work was, as narrated above, to make
a new analysis of the supposed substance. This analysis, duly written
out, was submitted to Sir Humphry, who, without stating precisely what
results he anticipated might follow, suggested heating the hydrate
under pressure in a hermetically sealed glass tube. This Faraday did.
When so heated, the tube filled with a yellow atmosphere, and on
cooling was found to contain two liquids, one limpid and colourless
like water, the other of an oily appearance. Concerning this research
a curious story is told in the life of Davy. Dr. Paris, Davy’s friend
and biographer, happened to visit the laboratory while Faraday was at
work on these tubes. Seeing the oily liquid, he ventured to rally the
young assistant upon his carelessness in employing greasy tubes. Later
in the day, Faraday, on filing off the end of the tube, was startled by
finding the contents suddenly to explode; the oily matter completely
disappearing. He speedily ascertained the cause. The gas, liberated
from combination with water by heat, had under the pressure of its own
evolution liquefied itself, only to re-expand with violence when the
tube was opened. Early the next day Dr. Paris received the following
laconic note:--

    DEAR SIR,--

    The _oil_ you noticed yesterday turns out to be liquid chlorine.

                                        Yours faithfully,
                                                  M. FARADAY.

Later he adopted a compressing syringe to condense the gas, and again
succeeded in liquefying it. Davy, who added a characteristic note to
Faraday’s published paper, immediately applied the same method of
liquefaction by its own pressure to hydrochloric acid gas; and Faraday
reduced a number of other gases by the same means. These researches
were not without danger. In the preliminary experiments an explosion
of one of the tubes drove thirteen fragments of glass into Faraday’s
eye. At the end of the year he drew up a historical statement on the
liquefaction of gases, which was published in the _Quarterly Journal_
for January, 1824. A further statement by him was published in the
_Philosophical Magazine_ for 1836; and in 1844 his further researches
on the liquefaction of gases were published in the _Philosophical
Transactions_.

In 1824 Faraday again brought to the Royal Society a chemical discovery
of first importance. The paper was on some new compounds of carbon and
hydrogen, and on certain other products obtained during decomposition
of oil by heat. From condensed oil-gas, so obtained, Faraday succeeded
in separating the liquid known as benzin or benzol, or, as he named it
at the time, bicarburet of hydrogen. It has since its discovery formed
the basis of several great chemical industries, and is manufactured in
vast quantities. Prior to the reading of this paper he had, as we have
already related, been elected a Fellow of the Royal Society, an honour
to which he had for some years aspired, and which stood alone in his
regard above the scientific honours of later years.

In this year he tried, amongst his unsuccessful experiments, two of
singular interest. One was an attempt to find whether two crystals
(such as nitre) exercised upon one another any polar attractions like
those of two lodestones. He suspended them by fibres of cocoon silk,
and, finding this material not delicate enough, by spider-lines. The
other was an attempt to discover magneto-electricity. For various
reasons he concluded that the approximation of the pole of a powerful
magnet to a conductor carrying a current would have the effect of
diminishing the amount of that current. He placed magnets within a
copper wire helix, and observed with a galvanometer whether the current
sent through the circuit of the helix by a given battery was less when
the magnet was absent. The result was negative.

[Sidenote: RESEARCH ON OPTICAL GLASS.]

In this year also began the laborious researches on optical glass,
which though in themselves leading to no immediate success of
commercial value, nevertheless furnished Faraday with the material
essential at the time for the making of the most momentous of all
his discoveries. A committee had been appointed by the President and
Council of the Royal Society for the improvement of glass for optical
purposes, and Faraday was amongst those chosen to act upon it.

In 1825 the Royal Society Committee delegated the investigation of
optical glass to a sub-committee of three, Herschel (afterwards
Sir John), Dollond (the optician), and Faraday. The chemical part,
including the experimental manufacture, was entrusted to Faraday.
Dollond was to work the glass and test its qualities from the
instrument maker’s point of view, whilst Herschel was to examine
its refraction, dispersion, and other physical properties. This
sub-committee worked for nearly five years, though by the removal of
Herschel from England its number was reduced to two. In 1827 the work
became more arduous. Faraday thus writes:--

    The President and Council of the Royal Society applied to the
    President and Managers of the Royal Institution for leave to
    erect on their premises an experimental room with a furnace,
    for the purpose of continuing the investigation on the
    manufacture of optical glass. They were guided in this by the
    desire which the Royal Institution has always evinced to assist
    in the advancement of science; and the readiness with which the
    application was granted showed that no mistaken notion had been
    formed in this respect. As a member of both bodies, I felt much
    anxiety that the investigation should be successful. A room
    and furnaces were built at the Royal Institution in September,
    1827, and an assistant was engaged, Sergeant Anderson, of the
    Royal Artillery. He came on the 3rd of December.

Anderson, who was thus made assistant to Faraday, remained in that
capacity till his death in 1866. He was a most devoted servant. In a
footnote to the “Experimental Researches” (vol. iii. p. 3) Faraday in
1845 wrote of him:--

    I cannot resist the occasion that is thus offered me of
    mentioning the name of Mr. Anderson, who came to me as an
    assistant in the glass experiments, and has remained ever since
    in the laboratory of the Royal Institution. He assisted me in
    all the researches into which I have entered since that time;
    and to his care, steadiness, exactitude, and faithfulness in
    the performance of all that has been committed to his charge, I
    am much indebted.--M. F.

Tyndall, who had a great admiration for Anderson, declared that
his merits as an assistant might be summed up in one phrase--blind
obedience. The story is told of him by Benjamin Abbott:--

[Sidenote: ANDERSON’S OBEDIENCE.]

    Sergeant Anderson ... was chosen simply because of the habits
    of strict obedience his military training had given him. His
    duty was to keep the furnaces always at the same heat, and the
    water in the ashpit always at the same level. In the evening
    he was released, but one night Faraday forgot to tell Anderson
    he could go home, and early next morning he found his faithful
    servant still stoking the glowing furnace, as he had been doing
    all night long.

The research on optical glass was viewed askance by several parties.
The expenditure of money which it involved was one of the “charges”
hurled against the Council of the Royal Society by Sir James South in
1830. Nevertheless it was deemed sufficiently important to receive
powerful support, as the following letter shows:--

                                        Admiralty, 20 Dec., 1827.

    SIR,

    I hereby request, on behalf of the Board of Longitude, that you
    will continue, in the furnace built at the Royal Institution,
    the experiments on glass, directed by the joint Committee
    of the Royal Society and the Board of Longitude and already
    sanctioned by the Treasury and the Board of Excise.

                              I am, Sir,
                                  Your obedient servant,
                                        THOMAS YOUNG, M.D.,
                                               Sec. Bd. Long.

  Michael Faraday, Esq.,
            Royal Institution.


In February, 1825, Faraday’s duties towards the Royal Institution were
somewhat modified. Hitherto he had been nominally a mere assistant
to Davy and Brande, though he had occasionally undertaken lectures
for the latter. Now, on Davy’s recommendation, he was, as we have
seen, appointed by the managers Director of the Laboratory under
the superintendence of the Professor of Chemistry. He was relieved,
“because of his occupation in research,” from his duty as chemical
assistant at the lectures.

The research on optical glass was not concluded till 1829, when
its results were communicated to the Royal Society in the Bakerian
lecture of that year--a memoir so long that it is said three sittings
were occupied in its delivery. It is printed _in extenso_ in the
_Philosophical Transactions_ of 1830. It opens as follows:--

    When the philosopher desires to apply glass in the construction
    of perfect instruments, and especially the achromatic
    telescope, its manufacture is found liable to imperfections so
    important and so difficult to avoid, that science is frequently
    stopped in her progress by them--a fact fully proved by the
    circumstance that Mr. Dollond, one of our first opticians, has
    not been able to obtain a disc of flint glass 4½ inches in
    diameter, fit for a telescope, within the last five years; or a
    similar disc, of 5 inches, within the last ten years.

    This led to the appointment by Sir H. Davy of the Royal Society
    Committee, and the Government removed the excise restrictions,
    and undertook to bear all the expenses as long as the
    investigation offered a reasonable hope of success.

    The experiments were begun at the Falcon Glass Works, three
    miles from the Royal Institution, and continued there in
    1825, 1826, and to Sept., 1827, when a room was built at the
    Institution. At first the inquiry was pursued principally as
    related to flint and crown glass; but in September, 1828, it
    was directed exclusively to the preparation and perfection of
    peculiar heavy and fusible glasses, from which time continued
    progress has been made.

In 1830 the experiments on glass-making were stopped.

In 1831 the Committee for the Improvement of Glass for Optical
Purposes reported to the Royal Society Council that the telescope made
with Mr. Faraday’s glass had been examined by Captain Kater and Mr.
Pond. “It bears as great a power as can reasonably be expected, and is
very achromatic. The Committee therefore recommend that Mr. Faraday be
requested to make a perfect piece of glass of the largest size that
his present apparatus will admit, and also to teach some person to
manufacture the glass for general sale.”

[Sidenote: GLASS-MAKING LAID ASIDE.]

In answer to this Faraday sent the following letter to Dr. Roget, Sec.
R.S.:--

    [_M. Faraday to P. M. Roget._]

                              Royal Institution, July 4, 1831.

    DEAR SIR,--I send you herewith four large and two small
    manuscript volumes relating to optical glass, and comprising
    the journal book and sub-committee book, since the period that
    experimental investigations commenced at the Royal Institution.

    With reference to the request which the Council of the
    Royal Society have done me the honour of making--namely,
    that I should continue the investigation--I should, under
    circumstances of perfect freedom, assent to it at once; but
    obliged as I have been to devote the whole of my spare time
    to the experiments already described, and consequently to
    resign the pursuit of such philosophical inquiries as suggested
    themselves to my own mind, I would wish, under the present
    circumstances, to lay the glass aside for a while, that I may
    enjoy the pleasure of working out my own thoughts on other
    subjects.

    If at a future time the investigation should be renewed, I must
    beg it to be clearly understood I cannot promise full success
    should I resume it: all that industry and my abilities can
    effect shall be done; but to perfect a manufacture, not being a
    manufacturer, is what I am not bold enough to promise.

                                        I am, &c.,
                                              M. FARADAY.


The optical glass was a failure, so far as concerned the original hope
that it would lead to great improvements in telescopes. Nevertheless
it furnished scientific men with a new material, the “heavy glass”
consisting essentially of boro-silicate of lead, for which sundry uses
in spectroscopy and other optical instruments have since been found.

In 1845 Faraday added this note:--

    I consider our results as negative, except as regards any
    good that may have resulted from my heavy glass in the hands
    of Amici (who applied it to microscopes) and in my late
    experiments on light.

These were the famous experiments on magneto-optics and diamagnetism.
Incidentally the research had led also to the permanent engagement of
Sergeant Anderson as assistant to Faraday.

[Sidenote: RESEARCHES AND LECTURES.]

During these years, from 1825 to 1829, which had been thus occupied in
an apparently fruitless quest, he had been far from idle. He had gone
on contributing chemical papers to the _Philosophical Transactions_
and to the _Quarterly Journal_. These dealt with sulpho-naphthalic
acid, with the limits of vaporisation, with caoutchouc, bisulphide
of copper, the fluidity of sulphur and phosphorus, the diffusion of
gases, and the relation of water to hot polished surfaces. He had also
originated at the Royal Institution the Friday evening discourses (see
p. 33), the first of which he held in 1826. For some years he himself
delivered no inconsiderable portion of these discourses every session.
In 1826 he gave six, in 1827 three, in 1828 five, in 1829 six, and
these in addition to his regular afternoon courses of six or eight
lectures on some connected subject. He had also, in 1826, begun the
Christmas lectures adapted to a juvenile audience, and had in 1827
given a course of twelve lectures at the London Institution in Finsbury
Circus. In addition to these labours he had, in 1827, brought out the
first edition of his book on “Chemical Manipulation.” In 1829 he began
his lectures at the Royal Military Academy at Woolwich, which continued
till 1849.

The year 1830 may be regarded as the close of the first period of
Faraday’s researches, during which time, though much of his labour
had been of a preparatory and even desultory kind, it had been a
training for the higher work to come. He had made three notable
discoveries in chemistry, the new substances benzol and butylene, and
the solubility of naphthalene in sulphuric acid forming the first of a
new class of bodies, the sulpho-acids. He had also made an important
discovery in physics, that of the electromagnetic rotations. He had
already published sixty original papers, besides many notes of lesser
importance, nine of these papers being memoirs in the _Philosophical
Transactions_. He had already begun to receive from learned societies,
academies, and universities the recognition of his scientific
attainments, and he had established firmly both his own reputation as
a lecturer, and the reputation of the Royal Institution, which was the
scene of his lectures.




CHAPTER IV.

SCIENTIFIC RESEARCHES: SECOND PERIOD.


With the year 1831 begins the period of the celebrated “Experimental
Researches in Electricity and Magnetism.” During the years which had
elapsed since his discovery of the electromagnetic rotations in 1823,
Faraday, though occupied, as we have seen, with other matters, had
not ceased to ponder the relation between the magnet and the electric
current. The great discoveries of Oersted, Ampère, and Arago had
culminated in England in two results: in Faraday’s discovery that the
wire which carries an electric current tends to revolve around the pole
of a neighbouring magnet; and in Sturgeon’s invention of the soft-iron
electromagnet, a core of iron surrounded by a coil of copper wire,
capable of acting as a magnet at will when the electric current is
transmitted to the coil and so caused to circulate around the iron core.

[Sidenote: FORESHADOWINGS.]

This production of magnetism from electricity, at will, and at a
distance, by the simple device of sending the electricity to circulate
as a current around the central core of iron was then, as now, a cause
of much speculation. The iron core which is to be made temporarily
into a magnet stands alone, isolated. Though surrounded outwardly
by the magnetising coil of copper wire, it does not touch it; nay,
must be screened from contact with it by appropriate insulation. The
electric current entering the copper coil at one end is confined from
leaving the copper wire by any lateral path: it must circulate around
each and every convolution, nor be permitted to flow back by the
return-wire until it has performed the required amount of circulation.
That the mere external circulation of electric current around a totally
disconnected interior core of iron should magnetise that core; that
the magnetisation should be maintained so long as the circulation of
electricity is maintained; and that the magnetising forces should cease
so soon as the current is stopped, are facts, familiar enough to every
beginner in the science, but mysterious enough from the abstract point
of view. Faraday was firmly persuaded that, great as had been these
discoveries of the production of magnetism and magnetic motions from
electricity, there remained other relations of no less importance to
be discovered. Again and again his mind recurred to the subject. If it
were possible to use electricity to produce magnetism, why should not
the converse be true? In 1822 his notebook suggestion was, as we have
seen, “Convert magnetism into electricity.” Yes, but how?

He possessed an intuitive bent of mind to inquire about the relations
of facts to one another. Convinced by sheer converse with nature in
the laboratory, of the correlation of forces and of the conservation
of energy long before either of those doctrines had received distinct
enunciation as principles of natural philosophy, he seems never to
have viewed an action without thinking of the necessary and appropriate
reaction; never to have deemed any physical relation complete in
which discovery had not been made of the converse relations for
which instinctively he sought. So in December, 1824, we find him
experimenting on the passage of a bar magnet through a helix of copper
wire (see _Quarterly Journal_ for July, 1825), but without result. In
November, 1825, he sought for evidence that might prove an electric
current in a wire to exercise an influence upon a neighbouring wire
connected to a galvanometer. But again, and yet again in December
of the same year, the entry stands “No result.” A third failure did
not convince him that the search was hopeless: it showed him that he
had not yet found the right method of experimenting. It is narrated
of him how at this period he used to carry in his waistcoat pocket a
small model of an electromagnetic circuit--a straight iron core about
an inch long, surrounded by a few spiral turns of copper wire--which
model he at spare moments would take out and contemplate, using it thus
objectively to concentrate his thoughts upon the problem to be solved.
A copper coil, an iron core. Given that electricity was flowing through
the one, it evoked magnetism in the other. What was the converse?
At first sight it might seem simple enough. Put magnetism from some
external source into the iron core, and then try whether on connecting
the copper coil to a galvanometer there was any indication of an
electric current. But this was exactly what was found not to result.

[Sidenote: OTHER MEN’S FAILURES.]

And not Faraday alone, but others, too, were foiled in the hope of
observing the expected converse. Not all who tried were as wise or
as frank as Faraday in confessing failure. Fresnel, in the height of
the fever of Oersted’s discovery, had announced to the Academy of
Sciences at Paris, on the 6th of November, 1820, that he had decomposed
water by means of a magnet which was laid motionless within a spiral
of wire. Emboldened by this announcement, Ampère remarked that he
too had noticed something in the way of production of currents from
a magnet. But before the end of the year both these statements were
withdrawn by their authors. Again, in the year 1822, Ampère, being at
Geneva, showed to Professor A. de la Rive in his laboratory a number of
electromagnetic experiments from his classical researches; and amongst
them one[20] which has been almost forgotten, but which, had it been
followed up, would assuredly have led Ampère to the discovery of the
induction of currents. In the experiment in question a thin copper
ring, made of a narrow strip folded into a circle, was hung inside
a circular coil of wire, traversed by a current. To this apparatus
a powerful horse-shoe magnet was presented; and De la Rive states
that, when the magnet was brought up, the suspended ring was observed
sometimes to move between the two limbs of the magnet, and sometimes
to be repelled from between them according to the sense of the current
in the surrounding coil. He and Ampère both attributed the effect to
temporary magnetism conferred upon the copper ring. Ampère himself
was at the time disposed to attribute it to the possible presence of
a little iron as an impurity in the copper. There are, however, some
discrepancies in the three published versions of the story. According
to Becquerel, Ampère had by 1825 satisfied himself of the non-existence
of induction currents.

[Sidenote: A PUZZLING EXPERIMENT.]

Quite independently, the question of the possibility of creating
currents by magnets was raised by another discovery, that of the
so-called “magnetism of rotation.” In 1824 Arago had observed that
a fine magnetic compass constructed for him by Gambey, having the
needle suspended in a cell, the base of which was a plate of pure
copper, was thereby damped in its oscillations, and instead of making
two or three hundred vibrations before it came to rest, as would be
the case in the open air, executed only three or four of rapidly
decreasing amplitude.[21] In vain did Dumas at the request of Arago
analyse the copper, in the supposition that iron might be present.
Inquiry compelled the conclusion that some other explanation must be
sought. And, reasoning from the apparent action of stationary copper
in bringing a moving magnetic needle to rest, he conjectured that a
moving mass of copper might produce motion in a stationary magnetic
needle. Accordingly he set into revolution, beneath a compass needle,
a flat disc of copper, and found that, even when a sheet of card or
glass was interposed to cut off all air-currents, the needle tended to
follow the moving copper disc, turning as if dragged by some invisible
influence. To the suggestion that mere rotation conferred upon copper
a sort of temporary magnetism Arago listened with some impatience. All
theories proposed to account for the phenomenon he discredited, even
though emanating from the great mathematician Poisson. He held his
judgment in absolute suspense. Babbage and Herschel measured the amount
of retarding force exerted on the needle by different materials, and
found the most effective to be silver and copper (which are the two
best conductors of electricity), after them gold and zinc, whilst lead,
mercury, and bismuth were inferior in power. The next year the same
experimenters announced the successful inversion of Arago’s experiment;
for by spinning the magnet underneath a pivoted copper disc they caused
the latter to rotate briskly. They also made the notable observation
that if slits are cut radially in the copper disc they diminish its
tendency to be dragged by the spinning magnet. Sturgeon showed that
the damping effect of a moving copper disc was diminished by the
presence of a second magnet pole of contrary kind placed beside the
first. All these things were most suggestive of the real explanation.
It clearly had something to do with the electric conductivity of
the metal disc, and therefore with electric currents. Sturgeon five
years later came very near to the explanation: after repeating the
experiments he concluded that the effect was an electric disturbance
in the copper disc, “a kind of reaction to that which takes place in
electromagnetism.”

Faraday knew of all the discussions which had arisen respecting
Arago’s rotations. They may have been the cause of his unsuccessful
attempts of 1824 and 1825. In April, 1828, for the fourth time he tried
to discover the currents which he was convinced must be producible
by the magnet, and for the fourth time without result. The cause of
failure was that both magnet and coil were at rest.

[Illustration: FIG. 4.]

The summer of 1831 witnessed him for the fifth time making the attack
on the problem thus persistently before him. In his laboratory
note-book he heads the research “Experiments on the production of
electricity from magnetism.” The following excellent summary of the
laboratory notes is taken from Bence Jones’s “Life and Letters”:--

    I have had an iron ring made (soft iron), iron round and ⅞ths
    of an inch thick, and ring six inches in external diameter.
    Wound many coils of copper round, one half of the coils being
    separated by twine and calico; there were three lengths of
    wire, each about twenty-four feet long, and they could be
    connected as one length, or used as separate lengths. By trials
    with a trough each was insulated from the other. Will call
    this side of the ring A. On the other side, but separated by
    an interval, was wound wire in two pieces, together amounting
    to about sixty feet in length, the direction being as with the
    former coils. This side call B.[22]

    Charged a battery of ten pairs of plates four inches square.
    Made the coil on B side one coil, and connected its extremities
    by a copper wire passing to a distance, and just over a
    magnetic needle (three feet from wire ring), then connected the
    ends of one of the pieces on A side with battery: immediately
    a sensible effect on needle. It oscillated and settled at last
    in original position. On breaking connection of A side with
    battery, again a disturbance of the needle.

[Sidenote: SUCCESS IN SIGHT.]

In the seventeenth paragraph, written on the 30th of August, he says,
“May not these transient effects be connected with causes of difference
between power of metals at rest and in motion in Arago’s experiments?”
After this he prepared fresh apparatus.

As was his manner, he wrote off to one of his friends a letter telling
what he was at work upon. On this occasion the recipient of his
confidences was his friend Phillips:--

    [_Michael Faraday to Richard Phillips._]

                                        Royal Institution.
                                                Sept. 23, 1831.

    MY DEAR PHILLIPS,

    I write now, though it may be some time before I send my
    letter, but that is of no great consequence. I received your
    letter to Dr. Reid and read it on the coach going to Hastings,
    where I have been passing a few weeks, and I fancy my fellow
    passengers thought I had got something very droll in hand;
    they sometimes started at my sudden bursts, especially when I
    had the moment before been very grave and serious amongst the
    proportions. As you say in the letter there are some new facts
    and they are always of value; otherwise I should have thought
    you had taken more trouble than the matter deserved. Your
    quotation from Boyle has nevertheless great force in it.

    I shall send with this a little thing in your own way “On the
    Alleged decline of science in England.” It is written by Dr.
    Moll of Utrecht, whose name may be mentioned in conversation
    though it is not printed in the pamphlet. I understand the
    view taken by Moll is not at all agreeable to some. “I do not
    know what business Moll had to interfere with our scientific
    disputes” is however the strongest observation I have heard of
    in reply.

    I do not think I thanked you for your last Pharmacopœia. I
    do so now very heartily. I shall detain this letter a few
    days that I may send a couple of my papers (_i.e._ a paper
    and appendix) with it, for though not chemical I think
    you will like to have them. I am busy just now again on
    Electro-Magnetism, and think I have got hold of a good thing,
    but can’t say; it may be a weed instead of a fish that after
    all my labour I may at last pull up. I think I know why metals
    are magnetic when in motion though not (generally) when at rest.

    We think about you all very much at times, and talk over
    affairs of Nelson Square, but I think we dwell more upon the
    illnesses and nursings and upon the sudden calls and chats
    rather than the regular parties. Pray remember us both to Mrs.
    Phillips and the damsils--I hope the word is not too familiar.

                                        I am Dear Phillips,
                                              Most Truly Yours,
                                                        M. FARADAY.

  R. Phillips, Esq.,
          &c., &c., &c.


[Sidenote: TEN DAYS OF SPLENDID WORK.]

September 24 was the third day of his experiments. He began (paragraph
21) by trying to find the effect of one helix of wire, carrying the
voltaic current of ten pairs of plates, upon another wire connected
with a galvanometer. “No induction sensible.” Longer and different
metallic helices (paragraph 22) showed no effect; so he gave up those
experiments for that day, and tried the effects of bar magnets instead
of the ring magnet he had used on the first day.

[Illustration: FIG. 5.]

In paragraph 33 he says:--

    An iron cylinder had a helix wound on it. The ends of the wires
    of the helix were connected with the indicating helix at a
    distance by copper wire. Then the iron placed between the poles
    of bar magnets as in accompanying figure (Fig. 5). Every time
    the magnetic contact at N or S was made or broken, there was
    magnetic motion at the indicating helix--the effect being, as
    in former cases, not permanent, but a mere momentary push or
    pull. But if the electric communication (_i.e_. by the copper
    wire) was broken, then the disjunction and contacts produced no
    effect whatever. Hence here distinct conversion of magnetism
    into electricity.

The fourth day of work was October 1. Paragraphs 36, 37, and 38
describe the discovery of induced voltaic currents:--

    36. A battery of ten troughs, each of ten pairs of plates four
    inches square, charged with good mixture of sulphuric and
    nitric acid, and the following experiments made with it in the
    following order.

    37. One of the coils (of a helix of copper wire 203 feet long)
    was connected with the flat helix, and the other (coil of same
    length round same block of wood) with the poles of the battery
    (it having been found that there was no metallic contact
    between the two); the magnetic needle at the indicating flat
    helix was affected, but so little as to be hardly sensible.

    38. In place of the indicating helix, our galvanometer was
    used, and then a sudden jerk was perceived when the battery
    communication was _made_ and _broken_, but it was so slight as
    to be scarcely visible. It was one way when made, the other
    when broken, and the needle took up its natural position at
    intermediate times.

    Hence there is an inducing effect without the presence of iron,
    but it is either very weak or else so sudden as not to have
    time to move the needle. I rather suspect it is the latter.

The fifth day of experiment was October 17. Paragraph 57 describes the
discovery of the production of electricity by the approximation of a
magnet to a wire:--

    A cylindrical bar magnet three-quarters of an inch in
    diameter, and eight inches and a half in length, had one end
    just inserted into the end of the helix cylinder (220 feet
    long); then it was quickly thrust in the whole length, and the
    _galvanometer_ needle moved; then pulled out, and again the
    _needle moved_, but in the opposite direction. This effect was
    repeated every time the magnet was put in or out, and therefore
    a wave of electricity was so produced from _mere approximation
    of a magnet_, and not from its formation _in situ_.

The cause of all the earlier failures was, then, that both magnet and
coil were at rest. The magnet might lie in or near the coil for a
century and cause no effect. But while moving towards the coil, or from
it, or by spinning near it, electric currents were at once induced.

The ninth day of his experiments was October 28, and this day
he “made a copper disc turn round between the poles of the great
horse-shoe magnet of the Royal Society. The axis and edge of the disc
were connected with a galvanometer. The needle moved as the disc
turned.” The next day that he made experiments, November 4, he found
“that a copper wire one-eighth of an inch drawn between the poles and
conductors produced the effect.” In his paper, when describing the
experiment, he speaks of the metal “cutting” the magnetic curves, and
in a note to his paper he says, “By magnetic curves I mean lines of
magnetic forces which would be depicted by iron filings.”

[Sidenote: SUCCESS AND ITS SECRET.]

We here come upon those “lines of force” which played so important a
part in these and many of Faraday’s later investigations. They were
known before Faraday’s time--had, in fact, been known for two hundred
years. Descartes had seen in them evidence for his hypothetical
vortices. Musschenbroek had mapped them. But it was reserved to Faraday
to point out their true significance. To the very end of his life he
continued to speculate and experiment upon them.

All this splendid work had occupied but a brief ten days. Then he
rearranged the facts which he had thus harvested, and wrote them out in
corrected form as the first series of his “Experimental Researches in
Electricity.” The memoir was read to the Royal Society on November 24,
1831, though it did not appear in printed form until January, 1832--a
delay which gave rise to serious misunderstandings. The paper having
been read, he went away to Brighton to take a holiday, and in the
exuberance of his heart penned the following letter[23] to Phillips:--

    [_M. Faraday to R. Phillips._]

                                        Brighton: November 29, 1831.

    DEAR PHILLIPS,--For once in my life I am able to sit down and
    write to you without feeling that my time is so little that my
    letter must of necessity be a short one and accordingly I have
    taken an extra large sheet of paper intending to fill it with
    news and yet as to news I have none for I withdraw more and
    more from Society, and all I have to say is about myself.

    But how are you getting on? are you comfortable? and how does
    Mrs. Phillips do; and the girls? Bad correspondant as I am, I
    think you owe me a letter and as in the course of half an hour
    you will be doubly in my debt pray write us, and let us know
    all about you. Mrs. Faraday wishes me not to forget to put her
    kind remembrances to you and Mrs. Phillips in my letter.

    To-morrow is St. Andrew’s day,[24] but we shall be here until
    Thursday. I have made arrangements to be _out_ of the Council
    and care little for the rest although I should as a matter of
    curiosity have liked to see the Duke in the chair on such an
    occasion.

    We are here to refresh. I have been working and writing a
    paper and that always knocks me up in health, but now I feel
    well again and able to pursue my subject and now I will tell
    you what it is about. The title will be, I think, EXPERIMENTAL
    RESEARCHES IN ELECTRICITY: §I. _On the induction of electric
    currents._ § II. _On the evolution of Electricity from
    magnetism._ § III. _On a New electrical condition of matter._
    § IV. _On Arago’s magnetic phenomena._ There is a bill of fare
    for you; and what is more I hope it will not disappoint you.
    Now the pith of all this I must give you very briefly; the
    demonstrations you shall have in the paper when printed--

    [Sidenote: THE PITH OF THE DISCOVERY.]

    § I. When an electric current is passed through one of two
    parallel wires it causes at first a current in the same
    direction[25] through the other, but this induced current does
    not last a moment, notwithstanding the inducing current (from
    the Voltaic battery) is continued all seems unchanged except
    that the principal current continues its course, but when the
    current is stopped then a return current occurs in the wire
    under induction of about the same intensity and momentary
    duration but in the opposite direction to that first found.
    Electricity in currents therefore exerts an inductive action
    like ordinary electricity but subject to peculiar laws: the
    effects are a current in the same direction when the induction
    is established: a reverse current when the induction ceases and
    a _peculiar state_ in the interim. Common electricity probably
    does the same thing but as it is at present impossible to
    separate the beginning and the end of a spark or discharge from
    each other, all the effects are simultaneous and neutralise
    each other--

    § II. Then I found that magnets would induce just like voltaic
    currents and by bringing helices and wires and jackets up to
    the poles of magnets, electrical currents were produced in
    them these currents being able to deflect the galvanometer, or
    to make, by means of the helix, magnetic needles, or in one
    case even to give a spark. Hence the evolution of _electricity
    from magnetism_. The currents were not permanent, they ceased
    the moment the wires ceased to approach the magnet because
    the new and apparently quiescent state was assumed just as in
    the case of the induction of currents. But when the magnet
    was removed, and its induction therefore ceased, the return
    currents appeared as before. These two kinds of induction
    I have distinguished by the terms _Volta-electric_ and
    _Magneto-electric_ induction. Their identity of action and
    results is, I think, a very powerful proof of the truth of M.
    Ampère’s theory of magnetism.

    [Sidenote: A JUBILANT EPISTLE.]

    § III. The new electrical condition which intervenes by
    induction between the beginning and end of the inducing current
    gives rise to some very curious results. It explains why
    chemical action or other results of electricity have never
    been as yet obtained in trials with the magnet. In fact, the
    currents have no sensible duration. I believe it will explain
    perfectly the _transference of elements_ between the poles
    of the pile in decomposition but this part of the subject I
    have reserved until the present experiments are completed
    and it is so analogous, in some of its effects to those of
    Ritter’s secondary piles, De la Rive and Van Beck’s peculiar
    properties of the poles of a voltaic pile, that I should
    not wonder if they all proved ultimately to depend on this
    state. The condition of matter I have dignified by the term
    _Electrotonic_, THE ELECTROTONIC STATE. What do you think of
    that? Am I not a bold man, ignorant as I am, to coin words
    but I have consulted the scholars,[26] and now for § IV. The
    new state has enabled me to make out and explain all Arago’s
    phenomena of the rotating magnet or copper plate, I believe,
    perfectly; but as great names are concerned Arago, Babbage,
    Herschel, &c., and as I have to differ from them, I have spoken
    with that modesty which you so well know you and I and John
    Frost[27] have in common, and for which the world so justly
    commends us. I am even half afraid to tell you what it is.
    You will think I am hoaxing you, or else in your compassion
    you may conclude I am deceiving myself. However, you need do
    neither, but had better laugh, as I did most heartily when I
    found that it was neither attraction nor repulsion, but just
    one of _my old rotations_ in a new form. I cannot explain to
    you all the actions, which are very curious; but in consequence
    of the electrotonic state being assumed and lost as the
    parts of the plate whirl under the pole, and in consequence
    of magneto-electric induction, currents of electricity are
    formed in the direction of the radii; continuing, for simple
    reasons, as long as the motion continues, but ceasing when
    that ceases. Hence the wonder is explained that the metal has
    powers on the magnet when moving, but not when at rest. Hence
    is also explained the effect which Arago observed, and which
    made him contradict Babbage and Herschel, and say the power
    was repulsive; but, as a whole, it is really tangential. It
    is quite comfortable to me to find that experiment need not
    quail before mathematics, but is quite competent to rival
    it in discovery; and I am amused to find that what the high
    mathematicians have announced as the _essential condition_
    to the rotation--namely, that _time is required_--has so
    little foundation, that if the time could by possibility be
    anticipated instead of being required--_i.e._ if the currents
    could be formed _before_ the magnet came over the place instead
    of _after_--the effect would equally ensue. Adieu, dear
    Phillips.

    Excuse this egotistical letter from yours very faithfully,

                                        M. FARADAY.


The second section shows that Faraday had discovered the cause of all
the previous failures to evoke electric currents in wires by means of a
magnet: it required _relative motion_. What the magnet at rest fails to
do, the magnet in motion accomplishes. This crucial point is admirably
commemorated in the following impromptu given by Mr. Herbert Mayo to
Sir Charles Wheatstone:--

  Around the magnet Faraday
  Was sure that Volta’s lightnings play:
      But how to draw them from the wire?
  He took a lesson from the heart:
  ’Tis when we meet, ’tis when we part,
      Breaks forth the electric fire.

Faraday’s holiday was brief; by December 5 he was again at work on his
researches. He re-observed the directions of the induced currents about
which, as the slip in his letter to Phillips shows, his mind was in
some doubt. Then on December 14th comes the entry:--“Tried the effects
of terrestrial magnetism in evolving electricity. Obtained beautiful
results.”

“The helix had the soft iron cylinder (freed from magnetism by a full
red heat and cooling slowly) put into it, and it was then connected
with the galvanometer by wires eight foot long; then inverted the bar
and helix, and immediately the needle moved; inverted it again, the
needle moved back; and, by repeating the motion with the oscillations
of the needle, made the latter vibrate 180°, or more.”

The same day he “made Arago’s experiment with the earth magnet, only no
magnet used, but the plate put horizontal and rotated. The effect at
the needle was slight but very distinct.... Hence Arago’s plate a new
electrical machine.”

[Sidenote: POINTS IN THE DISCOVERY.]

When we compare these manuscript notes, recording the experiments in
the order in which they were made with the published account of them
in the “Experimental Researches,” we find many of them transcribed
almost verbatim. But there is a difference in the order of their
arrangement. In point of time the experiments on the evolution of
electricity from magnetism, beginning with the ring (p. 108), preceded
those on the induction of a current by another current. In the printed
“Researches” the experiments on the induction of currents are put
first, with an introductory paragraph on the general phenomenon of
induction.[28] Faraday’s habit of working up an experiment--whether
successful or unsuccessful--by increasing the power to the maximum
available is illustrated in the course of the experiments on the iron
ring. At first he used a battery of ten pairs of plates four inches
square. Then, having been eminently successful in producing deflexions
of his galvanometer, he increased the battery to one hundred pairs of
plates, with the result that when contact was completed or broken in
the primary circuit the impulse on the galvanometer in the secondary
circuit was so great as to make the needle spin round rapidly four
or five times before its motion was reduced to a mere oscillation.
Then he removed the galvanometer and fixed small pencils of charcoal
to the ends of the secondary helix; and to his great joy perceived a
minute _spark_ between the lightly touching charcoal points whenever
the contact of the battery to the primary helix was completed. This
was the first transformer, for the first time set--on a small
scale--to produce a tiny electric light. The spark he regarded as a
precious indication that what he was producing really was an electric
current. Using the great compound steel magnet of the Royal Society
(constructed by Dr. Gowin Knight) at Christie’s house at Woolwich
he had, as narrated above, also obtained a spark from the induced
current. For some time he failed to obtain either physiological or
chemical effects. But upon repeating the experiments more at leisure
at the Royal Institution, with Daniell’s armed loadstone capable of
lifting thirty pounds, a frog was found to be convulsed very strongly
each time magnetic contact between the magnet and the iron core of the
experimental coil was made or broken.

The absence of evidence as to chemical action seemed still to
disquiet him. He wanted to be sure that his induced currents would
do everything that ordinary voltaic currents would do. Failing the
final proof from chemical action, he rested the case on the other
identical properties. “But an agent,” he says, “which is conducted
along metallic wires in the manner described; which, whilst so passing,
possesses the peculiar magnetic actions and force of a current of
electricity; which can agitate and convulse the limbs of a frog;
and which, finally, can produce a spark by its discharge through
charcoal, can only be electricity. As all the effects can be produced
by ferruginous electro-magnets, there is no doubt that arrangements
like the magnets of Professors Moll, Henry, Ten Eyke, and others, in
which as many as two thousand pounds have been lifted, may be used
for these experiments; in which case not only a brighter spark may be
obtained, but wires also ignited, and as the currents can pass liquids,
chemical action be produced. These effects are still more likely to
be obtained when the magneto-electric arrangements, to be explained
in the fourth section, are excited by the powers of such apparatus.”
The apparatus described in the fourth section comprised several forms
of magneto-electric machines, that is to say, primitive kinds of
dynamos. Having in his mind the phenomenon discovered by Arago, and
the experiments of Babbage and Herschel on the so-called magnetism of
rotation, he followed up the idea that these effects might be due to
induced currents eddying round in the copper disc. No sooner had he
obtained electricity from magnets than he attempted to make Arago’s
experiment a new source of electricity, and, as he himself says, “did
not despair” “of being able to construct a new electrical machine.”

[Illustration: FIG. 6. (FACSIMILE OF ORIGINAL SKETCH.)]

[Sidenote: A NEW ELECTRICAL MACHINE.]

The “new electrical machine” was an exceedingly simple contrivance. A
disc of copper, twelve inches in diameter (Fig. 6), and about one-fifth
of an inch in thickness, fixed upon a brass axle, was mounted in
frames, so as to allow of revolution, its edge being at the same time
introduced between the magnetic poles of a large compound permanent
magnet, the poles being about half an inch apart.[29] The magnet first
used was the historical magnet of Gowin Knight. The edge of the plate
was well amalgamated, for the purpose of obtaining a good but movable
contact, and a part round the axle was also prepared in a similar
manner. Conducting strips of copper and lead, to serve as electric
collectors, were prepared, so as to be placed in contact with the edge
of the copper disc; one of these was held by hand to touch the edge
of the disc between the magnet poles. The wires from a galvanometer
were connected, the one to the collecting-strip, the other to the
brass axle; then on revolving the disc a deflexion of the galvanometer
was obtained, which was reversed in direction when the direction of
the rotation was reversed. “Here, therefore, was demonstrated the
production of a permanent current of electricity by ordinary magnets.”
These effects were also obtained from the poles of electro-magnets,
and from copper helices without iron cores. Several other forms of
magneto-electric machines were tried by Faraday.

[Sidenote: NEW FORMS OF APPARATUS.]

[Illustration: FIG. 7.]

In one,[30] a flat ring of twelve inches’ external diameter, and one
inch broad, was cut from a thick copper plate, and mounted to revolve
between the poles of the magnet, two conductors being applied to
make rubbing contact at the inner and outer edge at the part which
passed between the magnetic poles. In another,[31] a disc of copper,
one-fifth of an inch thick and only 1½ inch in diameter (Fig. 7), was
amalgamated at the edge, and mounted on a copper axle. A square piece
of sheet metal had a circular hole cut in it, into which the disc
fitted loosely; a little mercury completed communication between the
disc and its surrounding ring. The latter was connected by wire to a
galvanometer; the other wire being connected from the instrument to the
end of the axle. Upon rotating the disc in a horizontal plane, currents
were obtained, though the earth was the only magnet employed.

[Illustration: FIG. 8.]

Faraday also proposed a multiple machine[32] having several discs,
metallically connected alternately at the edges and centres by means
of mercury, which were then to be revolved alternately in opposite
directions, In another apparatus,[33] a copper cylinder (Fig. 8),
closed at one extremity, was put over a magnet, one half of which
it enclosed like a cap, and to which it was attached without making
metallic contact. The arrangement was then floated upright in a narrow
jar of mercury, so that the lower edge of the copper cap touched the
fluid. On rotating the magnet and its attached cap, a current was sent
through wires from the mercury to the top of the copper cap. In another
apparatus,[34] still preserved at the Royal Institution, a cylindrical
bar magnet, half immersed in mercury, was made to rotate, and generated
a current, its own metal serving as a conductor. In another form,[35]
the cylindrical magnet was rotated horizontally about its own axis, and
was found to generate currents which flowed from the middle to the
ends, or _vice versâ_, according to the rotation. The description of
these new electrical machines is concluded with the following pregnant
words:--

[Sidenote: AN EARTH-INDUCTOR.]

    I have rather, however, been desirous of discovering new facts
    and relations dependent on magneto-electric induction, than of
    exalting the force of those already obtained; being assured
    that the latter would find their full development hereafter.

[Illustration: FIG. 9.]

In yet another machine (Fig. 9), constructed by Faraday some time
later,[36] a simple rectangle of copper wire _w_, attached to a frame,
was rotated about a horizontal axis placed east and west, and generated
alternate currents, which could be collected by a simple commutator _c_.

Within a few months machines on the principle of magneto-induction had
been devised by Dal Negro, and by Pixii. In the latter’s apparatus a
steel horseshoe magnet, with its poles upwards, was caused to rotate
about a vertical shaft, inducing alternating currents in a pair of
bobbins fixed above it, and provided with a horseshoe core of soft
iron. Later, in 1832, Pixii produced, at the suggestion of Ampère,[37]
a second machine, provided with mercury cup connections to rectify the
alternations of the current. One of these machines was shown at the
British Association meeting at Oxford in the same year (p. 64).

The idea developed in the third part of this research was intensely
original and suggestive. Faraday’s own statement is as follows:--

[Sidenote: THE ELECTROTONIC STATE.]

    Whilst the wire is subject to either volta-electric or
    magneto-electric induction, it appears to be in a peculiar
    state; for it resists the formation of an electrical current
    in it, whereas, if left in its common condition, such a
    current would be produced; and when left uninfluenced it has
    the power of originating a current, a power which the wire
    does not possess under common circumstances. This electrical
    condition of matter has not hitherto been recognised, but it
    probably exerts a very important influence in many, if not
    most, of the phenomena produced by currents of electricity. For
    reasons which will immediately appear, I have, after advising
    with several learned friends, ventured to designate it as the
    _electrotonic_ state.

    This peculiar condition shows no known electrical effects
    whilst it continues; nor have I yet been able to discover any
    peculiar powers exerted or properties possessed by matter
    whilst retained in this state.

       *       *       *       *       *

    This state is altogether the effect of the induction exerted,
    and ceases as soon as the inductive force is removed.... The
    state appears to be instantly assumed, requiring hardly a
    sensible portion of time for that purpose.... In all those
    cases where the helices or wires are advanced towards or taken
    from the magnet, the direct or inverted current of induced
    electricity continues for the time occupied in the advance or
    recession; for the electro-tonic state is rising to a higher or
    falling to a lower degree during that time, and the change is
    accompanied by its corresponding evolution of electricity; but
    these form no objections to the opinion that the electro-tonic
    state is instantly assumed.

    This peculiar state appears to be a state of tension, and may
    be considered as _equivalent_ to a current of electricity,
    at least equal to that produced either when the condition is
    induced or destroyed.

Faraday further supposed that the formation of this state in the
neighbourhood of a coil would exert a reaction upon the original
current, giving rise to a retardation of it; but he was unable at
the time to ascertain experimentally whether this was so. He even
looked--though also unsuccessfully--for a self-induced return current
from a conductor of copper through which a strong current was led and
then suddenly interrupted, the expected current of reaction being “due
to the discharge of its supposed electrotonic state.”

If we would understand the rather obscure language in which this idea
of an electrotonic state is couched, we must try to put ourselves
back to the epoch when it was written. At that date the only ideas
which had been formulated to explain magnetic and electric attractions
and repulsions were founded upon the notion of action at a distance.
Michell had propounded the view that the electric and magnetic forces
vary, like gravity, according to a law of the inverse squares of the
distances. Coulomb, in a series of experiments requiring extraordinary
patience as well as delicacy of manipulation, had shown--by an
application of Michell’s torsion balance--that in particular cases
where the electric charges are concentrated on small spheres, or
where the magnetic poles are small, so as to act as mere points,
this law--which is essentially a geometric law of point-action--is
approximately fulfilled. The mathematicians, Laplace and Poisson at
their head, had seized on this demonstration and had elaborated their
mathematical theories. Before them, though the research lay for a
century unpublished, Cavendish had shown that the only law of force
as between one element of an electric charge and another compatible
with a charge being in equilibrium was the law of inverse squares.
But in all these mathematical reasonings one thing had been quite
left out of sight--namely, the possible properties of the intervening
medium. Faraday, to whom the idea of mere action at a distance was
abhorrent, if not unthinkable, conceived of all these forces of
attraction and repulsion as effects taking place by something going
on _in the intervening medium_, as effects propagated from point
to point continuously through space. In his earlier work on the
electromagnetic rotations he had grown to regard the space around
the conducting wire as being affected by the so-called current; and
the space about the poles of a magnet he knew to be traversed by
curved magnetic lines, invisible indeed, but real, needing only the
simplest of expedients--the sprinkling of iron filings--to reveal their
existence and trend. When therefore he found that these new effects of
the induction of one electric current by another could likewise cross
an intervening space, whether empty or filled with material bodies,
he instinctively sought to ascribe this propagation of the effect
to a property or state of the medium. And finding that state to be
different from any state previously known, different from the state
existing between two magnets at rest or between two stationary electric
charges, he followed the entirely philosophical course of exploring its
properties and of denoting it by a name which he deemed appropriate. As
we shall see, this idea of an electrotonic state recurred in his later
researches with new and important connotations.

[Illustration: FIG. 10.]

He was soon at work again, as we have seen.

He experimented, in January, 1832, on the currents produced by the
earth’s rotation--on the 10th at the round pond in Kensington Gardens,
and on the 12th and 13th at Waterloo Bridge.

[Sidenote: A SPARK FROM A MAGNET.]

“This evening,” he writes in his notebook under date February 8, “at
Woolwich, experimenting with magnet,[38] and for the first time got the
magnetic spark myself. Connected ends of a helix into two general ends,
and then crossed the wires in such a way that a blow at _a b_ would
open them a little [Fig. 10]. Then bringing _a b_ against the poles of
a magnet, the ends were disjoined, and bright sparks resulted.”

From succeeding with a steel magnet it was but a short step to
succeed when a natural loadstone was used. The next day we find this
entry:--“At home succeeded beautifully with Mr. Daniell’s magnet.
Amalgamation of wires very needful. This is a natural loadstone, and
perhaps the first used for the spark.”

He sent to the Royal Society an account of these and the earlier
experiments; his paper on terrestrial magneto-electric induction, and
on the force and direction of magneto-electric induction, received the
distinction of being read as the Bakerian lecture of the year.

[Sidenote: TYNDALL’S SUMMARY.]

The following summary of this second paper is from the pen of Professor
Tyndall:--

    He placed a bar of iron in a coil of wire, and lifting the
    bar into the direction of the dipping needle, he excited by
    this action a current in the coil. On reversing the bar, a
    current in the opposite direction rushed through the wire.
    The same effect was produced, when, on holding the helix in
    the line of dip, a bar of iron was thrust into it. Here,
    however, the earth acted on the coil through the intermediation
    of the bar of iron. He abandoned the bar, and simply set a
    copper plate spinning in a horizontal plane; he knew that the
    earth’s lines of magnetic force then crossed the plate at an
    angle of about 70°. When the plate spun round, the lines of
    force were intersected and induced currents generated, which
    produced their proper effect when carried from the plate to the
    galvanometer. “When the plate was in the magnetic meridian, or
    in any other plane coinciding with the magnetic dip, then its
    rotation produced no effect upon the galvanometer.”

    At the suggestion of a mind fruitful in suggestions of a
    profound and philosophic character--I mean that of Sir John
    Herschel--Mr. Barlow, of Woolwich, had experimented with
    a rotating iron shell. Mr. Christie had also performed an
    elaborate series of experiments on a rotating iron disc. Both
    of them had found that when in rotation the body exercised a
    peculiar action upon the magnetic needle, deflecting it in a
    manner which was not observed during quiescence; but neither
    of them was aware at the time of the agent which produced this
    extraordinary deflection. They ascribed it to some change in
    the magnetism of the iron shell and disc.

    But Faraday at once saw that his induced currents must come
    into play here, and he immediately obtained them from an iron
    disc. With a hollow brass ball, moreover, he produced the
    effects obtained by Mr. Barlow. Iron was in no way necessary;
    the only condition of success was that the rotating body
    should be of a character to admit of the formation of currents
    in its substance; it must, in other words, be a conductor of
    electricity. The higher the conducting power, the more copious
    were the currents. He now passes from his little brass globe
    to the globe of the earth. He plays like a magician with the
    earth’s magnetism. He sees the invisible lines along which
    its magnetic action is exerted, and, sweeping his wand across
    these lines, he evokes this new power. Placing a simple loop
    of wire round a magnetic needle, he bends its upper portion
    to the west; the north pole of the needle immediately swerves
    to the east; he bends his loop to the east, and the north
    pole moves to the west. Suspending a common bar magnet in a
    vertical position, he causes it to spin round its own axis.
    Its pole being connected with one end of a galvanometer wire,
    and its equator with the other end, electricity rushes round
    the galvanometer from the rotating magnet. He remarks upon the
    “_singular independence_” of the magnetism and the body of
    the magnet which carries it. The steel behaves as if it were
    isolated from its own magnetism.

    And then his thoughts suddenly widen, and he asks himself
    whether the rotating earth does not generate induced
    currents as it turns round its axis from west to east. In
    his experiment with the twirling magnet the galvanometer
    wire remained at rest; one portion of the circuit was in
    motion _relatively_ to _another portion_. But in the case of
    the twirling planet the galvanometer wire would necessarily
    be carried along with the earth; there would be no relative
    motion. What must be the consequence? Take the case of a
    telegraph wire with its two terminal plates dipped into the
    earth, and suppose the wire to lie in the magnetic meridian.
    The ground underneath the wire is influenced, like the wire
    itself, by the earth’s rotation; if a current from south to
    north be generated in the wire, a similar current from south
    to north would be generated in the earth under the wire; these
    currents would run against the same terminal plate, and thus
    neutralise each other.

    This inference appears inevitable, but his profound vision
    perceived its possible invalidity. He saw that it was at least
    possible that the difference of conducting power between
    the earth and the wire might give one an advantage over the
    other, and that thus a residual or differential current might
    be obtained. He combined wires of different materials, and
    caused them to act in opposition to each other, but found the
    combination ineffectual. The more copious flow in the better
    conductor was exactly counterbalanced by the resistance of the
    worst. Still, though experiment was thus emphatic, he would
    clear his mind of all discomfort by operating on the earth
    itself. He went to the round lake near Kensington Palace, and
    stretched 480 feet of copper wire, north and south, over the
    lake, causing plates soldered to the wire at its ends to dip
    into the water. The copper wire was severed at the middle,
    and the severed ends connected with a galvanometer. No effect
    whatever was observed. But though quiescent water gave no
    effect, moving water might. He therefore worked at Waterloo
    Bridge for three days, during the ebb and flow of the tide, but
    without any satisfactory result. Still he urges, “Theoretically
    it seems a necessary consequence, that where water is flowing
    there electric currents should be formed. If a line be imagined
    passing from Dover to Calais through the sea and returning
    through the land, beneath the water, to Dover, it traces out
    a circuit of conducting matter, one part of which, when the
    water moves up or down the Channel, is cutting the magnetic
    curves of the earth, whilst the other is relatively at rest....
    There is every reason to believe that currents do run in the
    general direction of the circuit described, either one way or
    the other, according as the passage of the waters is up or down
    the Channel.” This was written before the submarine cable was
    thought of, and he once informed me that actual observation
    upon that cable had been found to be in accordance with his
    theoretic deduction.

[Illustration: FIG. 11.]

It may here be apposite to discuss a fundamental question raised in
these researches. In Faraday’s mind there arose the conviction of
a connection between the induction of currents by magnets and the
magnetic lines which invisibly fill all the space in the neighbourhood
of the magnet. That relation he discovered and announced in the
following terms:--

[Sidenote: THE LAW OF INDUCTION.]

“The relation which holds between the magnetic pole, the moving wire
or metal, and the direction of the current evolved--_i.e._ _the
law_ which governs the evolution of electricity by magneto-electric
induction, is very simple, though rather difficult to express. If in
Fig. 11, P N represent a horizontal wire passing by a marked [_i.e._
‘north-seeking’] magnetic pole, so that the direction of its motion
shall coincide with the curved line proceeding from below upwards; or
if its motion parallel to itself be in a line tangential to the curved
line, but in the general direction of the arrows; or if it pass the
pole in other directions, but so as to cut the magnetic curves[39] in
the same general direction, or on the same side as they would be cut by
the wire if moving along the dotted curved line; then the current of
electricity in the wire is from P to N. If it be carried in the reverse
direction, the electric current will be from N to P. Or if the wire be
in the vertical position, figured P´ N´, and it be carried in similar
directions, coinciding with the dotted horizontal curve so far as to
cut the magnetic curves on the same side with it, the current will be
from P´ to N´.”

[Sidenote: CUTTING THE MAGNETIC LINES.]

When resuming the research in December, Faraday investigated the
point whether it was essential or not that the moving wire should,
in “cutting” the magnetic curves, pass into positions of greater or
lesser magnetic force; or whether, always intersecting curves of equal
magnetic intensity, the mere motion sufficed for the production of the
current. He found the latter to be true. This notion of _cutting_ the
invisible magnetic lines as the essential act necessary and sufficient
for induction was entirely original with Faraday. For long it proved
a stumbling-block to the abstract mathematicians, since there was, in
most cases, no direct or easy way in which to express the number of
magnetic lines that were cut. Neither had any convention been adopted
up to that time as to how to reckon numerically the number of magnetic
lines in any given space near a magnet. Later, in 1851, Faraday himself
gave greater precision to these ideas. He found that the current was
proportional to the velocity, when the conductor was moving in a
uniform magnetic field with a uniform motion. Also, that the quantity
of electricity thrown by induction into the circuit was directly
proportional to the “amount of curves intersected.” The following
passage, from Clerk Maxwell’s article on Faraday in the “Encyclopædia
Britannica,” admirably sums up the matter:--

    The magnitude and originality of Faraday’s achievement may be
    estimated by tracing the subsequent history of his discovery.
    As might be expected, it was at once made the subject of
    investigation by the whole scientific world, but some of the
    most experienced physicists were unable to avoid mistakes in
    stating, in what they conceived to be more scientific language
    than Faraday’s, the phenomena before them. Up to the present
    time the mathematicians who have rejected Faraday’s method of
    stating his law as unworthy of the precision of their science,
    have never succeeded in devising any essentially different
    formula which shall fully express the phenomena without
    introducing hypotheses about the mutual action of things which
    have no physical existence, such as elements of currents which
    flow out of nothing, then along a wire, and finally sink into
    nothing again.

    After nearly half a century of labour of this kind, we may say
    that, though the practical applications of Faraday’s discovery
    have increased and are increasing in number and value every
    year, no exception to the statement of these laws as given by
    Faraday has been discovered, no new law has been added to them,
    and Faraday’s original statement remains to this day the only
    one which asserts no more than can be verified by experiment,
    and the only one by which the theory of the phenomena can
    be expressed in a manner which is exactly and numerically
    accurate, and at the same time within the range of elementary
    methods of exposition.

In the year 1831, which witnessed this masterpiece of scientific
research, Faraday was busy in many other ways. He was still undertaking
chemical analyses and expert work for fees, as witness his letter to
Phillips on p. 62. He was also, until November, on the Council of the
Royal Society. To the “Philosophical Transactions” he contributed
a paper “On Vibrating Surfaces,” in which he solved a problem in
acoustics which had previously gone without explanation. It had long
been known that in the experiments of obtaining the patterns called
“Chladni’s figures,” by strewing powders upon vibrating plates, while
the heavier powders, such as sand, moved into the nodal lines, lighter
substances, such as lycopodium dust, collected in little circular
heaps over the parts where the vibration was most energetic. Faraday’s
explanation was that these lighter powders were caught and whirled
about in little vortices which formed themselves at spots where the
motions were of greatest amplitude.

He also wrote a paper “On a Peculiar Class of Optical Deceptions,”
dealing with the illusions that result from the eye being shown in
successive glimpses, as between the teeth of a revolving wheel,
different views of a moving body. This research was, in effect, the
starting point of a whole line of optical toys, beginning with the
phenakistiscope or stroboscope, which developed through the zoetrope
and praxino-scope into the kinematograph and animatograph of recent
date.

[Sidenote: LECTURES ON PHYSICAL SUBJECTS.]

He gave four afternoon lectures at the Royal Institution and five
Friday evening discourses. These were on optical deceptions, on light
and phosphorescence, being an account of experiments recently made by
Mr. Pearsall, chemical assistant in the Institution; on oxalamide, then
recently discovered by M. Dumas; on Trevelyan’s experiments about the
production of sound by heated bodies; and on the arrangements assumed
by particles upon vibrating surfaces.

In 1832 he gave five Friday evening discourses, four of which related
to his own researches. In August he entered upon the third series
of “Experimental Researches in Electricity,” which was devoted to
the identity of electricities derived from different sources, and on
the relation by measure of common [_i.e._ frictional] and voltaic
electricity. He did not like any doubt to hang about as to whether
the electricity obtained from magnets by induction was really the
same as that obtainable from other sources. Possibly he had in his
mind the difficulties which had arisen thirty years before over the
discoveries of Galvani and Volta, when it was so far doubted whether
the electricity in currents from piles and batteries of cells was
the same as the electricity evoked by friction, that the distinctive
and misleading name of “galvanism” was assigned to the former.
He commented on the circumstance that many philosophers--and he
included Davy by name in an explicit reference--were vainly drawing
distinctions[40] between electricities from different sources, or at
least doubting whether their identity were proven. His first point
was to consider whether “common electricity,” “animal electricity,”
and “magneto-electric currents” could, like “voltaic electricity,”
produce chemical decompositions. He began by demonstrating that an
ordinary electric discharge from a friction machine can affect a
suitably disposed galvanometer. One of his instruments of sufficient
sensitiveness was surrounded by an enclosing cage of double metal
foil and wire-work, duly connected to “earth,” so as to render it
independent of all disturbances by external electric charges in its
neighbourhood. His “earth” for this purpose consisted of a stout metal
wire connected through the pipes in the house to the metallic gas-pipes
belonging to the public gas works of London, and also with the metallic
water-pipes of London--an effectual “discharging train.” He used a
friction electric machine with a glass plate 50 inches in diameter,
and a Leyden-jar battery of fifteen jars, each having about 84 square
inches of coated glass. This battery of jars was first charged from the
machine and then discharged through a wet thread four feet long, and
through the galvanometer to earth _viâ_ the “discharging train.” Having
by this means satisfied himself that these electric discharges could
deflect a galvanometer, whether through the wet thread, a copper wire,
or through water, or rarefied air, or by connection through points in
air, he went on to the question of chemical decomposition. Dipping two
silver wires into a drop of solution of sulphate of copper, he found
that one of them became copper-plated by the electricity that was
evolved by 100 or 200 turns of the disc machine. He bleached indigo,
turned starch purple with iodine liberated from iodide of potassium,
exactly as might have been done by a “volta-electric current” from a
battery of cells. He also decomposed water, giving due recognition to
the antecedent experiments of Van Troostwyk, Pearson, and Wollaston.

[Sidenote: IDENTITY OF ELECTRICITIES.]

In the paper which he drew up he compares these results with others
made with electric discharges from an electric kite and with those of
the torpedo and other electric fishes. He recapitulates the properties
of magneto-electricity and the proofs now accumulating that it can
decompose water. He drew up a schedule of the different effects which
electricity can produce, and of the different sources of electricity,
showing in tabular form how far each so-called kind of electricity
had been found to produce each effect. The conclusion was that there
is no philosophical difference between the different cases; since the
phenomena produced by the different kinds of electricity differ not in
their character but only in degree. “_Electricity, whatever may be its
source, is identical in its nature._” On comparing the effects produced
by different discharges, he concludes that “if the same absolute
quantity[41] of electricity pass through the galvanometer, whatever may
be its intensity, the deflecting force upon the magnetic needle is the
same.” He was then able to go on to a quantitative comparison between
the “quantity” of electricity from different sources, and came to the
conclusion that both in magnetic deflection and in chemical force the
current of electricity given by his standard battery for eight beats of
his watch was equal to that of the friction machine evolved by thirty
revolutions; further, that “the chemical power, like the magnetic
force, is in direct proportion to the absolute quantity of electricity
which passes.”

[Sidenote: ELECTRO-CHEMICAL WORK.]

This series of researches was published in January, 1833. In April
of the same year he sent to the Royal Society another paper--the
fourth series--on electric conduction. It arose from the surprising
observation that, though water conducts, ice acts as a complete
non-conductor. This led to an examination of the conducting power of
fusible solids in general. He found that as a rule--excepting on the
one hand the metals, which conduct whether solid or liquid, and on the
other hand fatty bodies, which are always non-conductors--they assume
conducting power when liquefied, and lose it when congealed. Chloride
of lead, of silver, of potassium, and of sodium, and many chlorates,
nitrates, sulphates, and many other salts and fusible substances were
found to follow this rule. All the substances so found to act were
compound bodies, and capable of decomposition by the current. When
conduction ceased, decomposition ceased also. An apparent exception was
found in sulphide of silver, which, when heated, acquired conducting
powers even before it assumed the liquid state, yet decomposed in the
solid state. This led him on to study electro-chemical decompositions
more closely. Here he was following directly in the footsteps of his
master Davy, whose discovery of the decomposition of potash and soda
by the electric current had been one of the most prominent scientific
advances resulting from the invention of the voltaic cell. The fifth
series of researches, published in June, 1833, embodies the work. He
first combats the prevailing opinion that the presence of water is
necessary for electro-chemical decomposition; then analyses the views
of various philosophers--Grotthuss, Davy, De la Rive, and others--who
had discussed the question whether the decompositions are due to
attractions exercised by the two poles of the electric circuit. This he
contests in the most direct manner. Already he has reason to believe
that for a given quantity of electricity passed through the liquid
the amount of electro-chemical action is a constant quantity, and
depends in no way on the distance of the particles of the decomposable
substance from the poles. He regards the elements as progressing in two
streams in opposite directions parallel to the current, while the poles
“are merely the surfaces or doors by which the electricity enters into
or passes out of the substance suffering decomposition.”

Amongst the laboratory notes of this time are many which were never
published in the “Experimental Researches,” or of which only brief
abstracts appeared. Some of these are of great interest.

Here is one literally transcribed:--

    26 Feb. 1833.

    _Chloride Magnesium._--When solid and wire fuzed in
    non-conductor--When fuzed conducted very well and was
    decomposed A and P Pole much action and gas--chlorine? At N
    Pole Magnesium separated and no gas. Sometimes Magnesium burnt
    flying off in globules burning brilliantly. When wire at that
    pole put in water or white M A [muriatic acid] matter round
    it acted powerfully evolving hydrogen and forming Magnesia;
    and when wire and surrounding matter heated in spirit lamp
    _Magnesium_ burnt with intense light into _Magnesia_. VERY GOOD
    EXPT.

This recalls the “capital experiment” entry which Sir Humphry Davy
wrote after the account of his decomposition of caustic potash. On the
7th of April we come to a marvellous page of speculations. He has seen
that liquids, both solutions and fused salts, can be decomposed by
the current, and that at least one solid is capable of electrolysis.
But he finds that alloys and metals are not decomposed. He finds
that electrolysis is easiest for those compounds that consist of the
most diverse elements, and is led on to speculate as to the possible
constitution of those conductors that the current does not decompose.
This may involve a recasting of accepted ideas; but from such a step he
does not shrink, as the following extracts show:--

    Metals _may_ not be compounds of elements most frequently
    combined, but rather of such as are so similar to each other as
    to pass out of the limit of voltaic decomposition.

    13th April (same page).

    If voltaic decomposition of the kind I believe then review
    all substances upon the new view to see if they may not be
    decomposable, &c. &c. &c.

[Sidenote: ATTRACTION BY POLES DOUBTED.]

He has now found that the facts observed do not admit of being
explained on the supposition that the motion of the ions is due to the
attraction of the poles, and accordingly there follows the entry:--

    (Ap. 13, 1833.)

    A single element is never attracted by a pole, _i.e._ without
    attraction of other element at other pole. Hence doubt Mr.
    Brande’s Expts on attraction of gases and vapours. Doubt
    attraction by poles altogether.

To this subject he returned in 1834; an intervening memoir--the
sixth--being taken up with the power of metals and solids to bring
about the combination of gaseous bodies. In the seventh series,
published in January, 1834, his first work is to explain the new
terms which he has adopted, on the advice of Whewell, to express the
facts. The so-called poles, being in his view merely doors or ways by
which the current passes, he now terms _electrodes_, distinguishing
the entrance and exit respectively as _anode_ and _cathode_,[42]
while the decomposable liquid is termed an _electrolyte_, and the
decomposing process _electrolysis_. “Finally,” he says, in a passage
(here italicised) worthy to be engraved in gold for the essential
truth it enunciates on a question of terminology, “I require a term to
express those bodies which can pass to the _electrodes_, or, as they
are usually called, the poles. Substances are frequently spoken of as
being _electronegative_, or _electropositive_, according as they go
under the supposed influence of a direct attraction to the positive or
negative pole. But these terms are much too significant for the use to
which I should have to put them; _for though the meanings are perhaps
right, they are only hypothetical, and may be wrong; and then, through
a very imperceptible but still very dangerous, because continual,
influence, they do great injury to science, by contracting and limiting
the habitual views of those engaged in pursuing it_. I propose to
distinguish such bodies by calling those _anions_ which go to the anode
of the decomposing body; and those passing to the _cathode_, _cations_;
and when I shall have occasion to speak of these together, I shall
call them _ions_.[43] Thus, the chloride of lead is an _electrolyte_,
and when _electrolyzed_ evolves the two _ions_, chlorine and lead, the
former being an _anion_ and the latter a _cation_.” In Faraday’s own
bound volume of the “Experimental Researches” he has illustrated these
terms by the sketch here reproduced. (Fig. 12.)

Faraday’s letter to Whewell when he consulted him as to the new words
has not been preserved. He discarded, when the paper was printed, the
terms he had first used. Whewell’s replies of April 25th and May 5th,
1834, have been preserved and are printed in Todhunter’s biography
of Whewell. From the later of the two the following passage is
extracted:--

[Sidenote: NEW NOMENCLATURE.]

    [_Whewell to Faraday_], May 5, 1834.

    If you take _anode_ and _cathode_, I would propose for the two
    elements resulting from _electrolysis_ the terms _anion_ and
    _cation_, which are neuter participles signifying _that which
    goes up_, and _that which goes down_; and for the two together
    you might use the term _ions_.... The word is not a substantive
    in Greek, but it may easily be so taken, and I am persuaded
    that the brevity and simplicity of the terms you will thus have
    will in a fortnight procure their universal acceptation. The
    _anion_ is that which goes to the _anode_, the _cation_ is that
    which goes to the _cathode_. The _th_ in the latter word arises
    from the aspirate in _hodos_ (way), and therefore is not to be
    introduced in cases where the second term has not an aspirate,
    as _ion_ has not.

[Illustration: FIG. 12.]

On May 15th Faraday replied as follows:--

    [_Faraday to Whewell._]

    I have taken your advice and the names, and use _anode_,
    _cathode_, _anions_, _cations_ and _ions_; the last I shall
    have but little occasion for. I had some hot objections made to
    them here, and found myself very much in the condition of the
    man with his Son and Ass, who tried to please everybody; but
    when I held up the shield of your authority it was wonderful
    to observe how the tone of objection melted away. I am quite
    delighted with the facility of expression which the new terms
    give me, and shall ever be your debtor for the kind assistance
    you have given me.

As though to prepare the way for a still further cutting of himself
adrift from the slavery of using terms that might be found misleading,
he added the following note:--

    It will be well understood that I am giving no opinion
    respecting the nature of the electric current now, beyond what
    I have done on former occasions; and that though I speak of
    the current as proceeding from the parts which are positive to
    those which are negative, it is merely in accordance with the
    conventional, though in some degree tacit, agreement entered
    into by scientific men, that they may have a constant, certain,
    and definite means of referring to the direction of the forces
    of that current.

The “former occasions” is a reference to an earlier suggestion that
a _current_ might mean anything progressive, whether a flow in one
direction or two fluids moving in opposite directions, or merely
vibrations, or, still more generally, progressive forces. He had
expressly said that what we call the electric current “may perhaps best
be conceived of as _an axis of power having contrary forces, exactly
equal in amount, in contrary directions_.”

[Sidenote: ELECTRO-CHEMICAL LAWS.]

He then suggests as a measurer of current the standard form of
electrolytic cell ever since known as the _voltameter_. He preferred
that kind in which water is decomposed, the quantity of electricity
which had flowed through it being measured by the quantity of the
gas or gases evolved during the operation. Before adopting this he
undertook careful experiments in which his fine manipulative skill, no
less than his chemical experience, was called into service to verify
the fact that the quantity of water decomposed was really proportionate
to the quantity of electricity which has been passed through the
instrument. Having this standard, he investigated numerous other cases
of decomposition by the current, and so arrived at a substantial basis
for the doctrine of _definite electro-chemical_ action. Speaking of
the substances into which electrolytes are divided by the current,
and which he had called ions, he says: “They are combining bodies;
are directly associated with the fundamental parts of the doctrine
of chemical affinity; and have each a definite proportion, in which
they are always evolved during electrolytic action.... I have proposed
to call the numbers representing the proportions in which they are
evolved _electro-chemical equivalents_. Thus hydrogen, oxygen,
chlorine, iodine, lead, tin are _ions_; the three former are _anions_,
the two metals _cations_, and 1, 8, 36, 125, 104, 58, are their
_electro-chemical equivalents_ nearly.”

This fundamental law being set upon an impregnable basis of facts,
he goes on to speculate upon the _absolute quantity_ of electricity
or electric power belonging to different bodies; a notion which only
within the last few years has found general acceptance.

In developing this theory he uses the following language:--

    According to it [_i.e._ this theory], the equivalent weights of
    bodies are simply those quantities of them which contain equal
    quantities of electricity, or have naturally equal electric
    powers; it being the ELECTRICITY which _determines_ the
    equivalent number, _because_ it determines the combining force.
    Or, if we adopt the atomic theory or phraseology, then the
    atoms of bodies which are equivalents to each other in their
    ordinary chemical action, have equal quantities of electricity
    naturally associated with them. But I must confess I am jealous
    of the term _atom_....

Here we find the modern doctrine of _electrons_ or unitary atomic
charges, clearly formulated in 1834. In the course of this speculation
he remarks that “if the electrical power which holds the elements of
a grain of water in combination, or which makes a grain of oxygen or
hydrogen in the right proportions unite into water when they are made
to combine, could be thrown into the condition of _a current_, it
would exactly equal the current required for the separation of that
grain of water into its elements again.” And all this years before
there was any doctrine of the conservation of energy to guide the mind
of the philosopher! The passage just cited contains the germs of the
thermodynamic theory of electromotive forces worked out a dozen years
later by Sir William Thomson (now Lord Kelvin), by which theory we can
predict the electromotive forces of any given chemical combination from
a knowledge of the heat evolved by a given mass of the product in the
act of combining.

[Sidenote: ANOTHER UNSUCCESSFUL QUEST.]

The eighth series of the researches, which was read in June, 1834,
deals chiefly with voltaic cells and batteries of cells. He is now
applying to the operations inside the primary cell the electrochemical
principles learned by the study of electrolysis in secondary cells.
His thoughts have been incessantly playing around the problem of
electrolytic conduction. He was convinced that the forces which shear
the anions from combination with the cations and transfer them in
opposite directions must be inherent before the circuit is completed,
and therefore before any actual transfer or movement takes place. “It
seems to me impossible,” he says, “to resist the idea that it [the
“transfer,” or “what is called the voltaic current”] must be preceded
by a _state of tension_ in the fluid. I have sought carefully for
indications of a state of tension in the electrolytic conductor; and
conceiving that it might produce something like structure, either
before or during its discharge, I endeavoured to make this evident by
polarised light.” He used a solution of sulphate of soda, but without
the slightest trace of optical action in any direction of the ray. He
repeated the experiment, using a solid electrolyte, borate of lead, in
its non-conducting state, but equally without result.

During the time of these electrochemical researches in 1833 and 1834,
Faraday’s activities for the Royal Institution were undiminished. In
1833 he gave seven Friday discourses, three of them on the researches
in hand, one on Wheatstone’s investigation of the velocity of the
electric spark, and one on the practical prevention of dry rot in
timber, which was afterwards republished as a pamphlet, and ran to
two editions. In 1834 he gave four Friday discourses; two on his
electrochemical researches, one on Ericsson’s heat-engine, and the
other on caoutchouc.

The ninth series of electrical researches occupied the autumn of 1834.
In it he returns to the study of the magnetic and inductive actions
of the current, investigating the self-induced spark at the break
of the circuit, to which his attention had been directed by Mr. W.
Jenkin. Several points in this research are little known even now to
electricians, the laboratory notes being much more detailed than the
published paper. He describes an exceedingly neat high-speed break
for producing rapid interruptions, using for that purpose stationary
ripples on the surface of a pool of mercury. In a wonderful day’s work
on 13th November, filling thirty-four pages of the laboratory book,
illustrated with numerous unpublished sketches, he tracks out the
properties of self-induction. He proves that the spark (on breaking
circuit) from a wire coiled up in a helix is far brighter than that
from an identical wire laid out straight. He finds that a non-inductive
and, therefore, sparkless coil can be made by winding the wire in two
opposite helices. “Thus the whole [inductive] effect of the length
of wire was neutralised by the reciprocal and contrary action of the
two halves which constituted the helices in contrary directions.” The
next day he writes: “These effects show that every part of an electric
circuit is acting by induction on the neighbouring parts of the same
current, even in the _same wire_ and the _same part_ of the wire.”

[Sidenote: EFFECTS OF SELF-INDUCTION.]

On 22nd November he is trying another set of experiments, also never
fully published. They relate to the diminution of self-induction of a
straight conductor by dividing it into several parallel strands at a
small distance apart from one another. The note in the laboratory book
runs thus:--

    Copper wire 1/23 of inch in diameter. Six lengths of five feet
    each, soldered at ends to piece of copper plate so as form
    terminations, and these amalgamated. When this bundle was used
    to connect the electro-motor it gave but very feeble spark on
    breaking contact, but the spark was sensibly better when the
    wires are held together so as to act laterally than when they
    were opened out from each other, thus showing lateral action.

    Made a larger bundle of the same fine copper wire. There were
    20 lengths of 18 feet 2 inches each and the thick terminal
    pieces of copper wire 6 inches long and ⅓ of inch thick.

[Illustration: FIG. 13.]

This bundle he compared with a length of 19 feet 6 inches of a single
copper wire ⅕ inch in diameter, having about equal sectional area. The
latter gave decidedly the largest sparks on breaking circuit.

Faraday did not see fit at this time to accept the idea, suggested
indeed by himself in 1831, that these effects of self-induction were
the analogue of momentum or inertia. That explanation he set aside
on finding that the same wire when coiled had greater self-inductive
action than when straight. Had he at that time grasped this analogy, he
would have seen that the very property which gives rise to the spark
at break of circuit also retards the rapid growth of a current; and
then the experiment described above would have shown him that Sir W.
Snow Harris was right in preferring flat copper ribbon to a round wire
of equivalent section as a material for lightning conductors. He was,
however, disappointed to find so small a difference between round wires
and parallel strands. The memoir as published contains an exceedingly
interesting conclusion:--

    Notwithstanding that the effects appear only at the making
    and breaking of contact (the current, remaining unaffected,
    seemingly, in the interval,) I cannot resist the impression
    that there is some connected and correspondent effect produced
    by this lateral action of the elements of the electric stream
    during the time of its continuance. An action of this kind,
    in fact, is evident in the magnetic relations of the parts
    of the current. But admitting (as we may do for the moment)
    the magnetic forces to constitute the power which produces
    such striking and different results at the commencement and
    termination of a current, still there appears to be a link in
    the chain of effects--a wheel in the physical mechanism of the
    action, as yet unrecognised.

The tenth series of researches, on the voltaic battery, though
completed in October, 1834, was not published till June, 1835.

[Sidenote: ACTION IN A MEDIUM.]

The next research, begun in the autumn of 1835, after a lull of
about eight months, lasted over two years. It was not completed till
December, 1837. This investigation took Faraday away from magnetic
and electrochemical matters to the old subject of statical electric
charges, a subject hitherto untouched in his researches. But he had
long brooded over the question as to the nature of an electric charge.
Over and over again, as he had watched the inductive effect of electric
currents acting from wire to wire, his mind turned to the old problem
of the inductive influence--discovered eighty years before, by John
Canton--exerted, apparently at a distance, by electric charges. He
had learned to distrust action at a distance, and now the time was
ripe for a searching inquiry as to whether electric _influence_, or
induction[44] as it was then called, was also an action propagated by
contiguous actions in the intervening medium.

Faraday had done no special electric work during the first nine months
of 1835. He had worked at a chemical investigation of fluorine through
the spring, and in July took a hurried tour in Switzerland, and
returned to work at fluorine. Not till November 3rd does he turn to the
subject over which he had been brooding. On that date, intercalated
between notes of his chemical studies, filling a dozen pages of the
laboratory book, are a magnificent series of speculations as to the
nature of charges, and on the part played by the electric--or, as we
should now say, the dielectric--medium. They begin thus:--

“Have been thinking much lately of the relation of common and
voltaic electricity, of induction by the former and decomposition by
the latter, and am quite convinced that there must be the closest
connection. Will be first needful to make out the true character”--note
the phrase--“of ordinary electrical phenomena.” The following notes
are for experiment and observation.

“Does common electricity reside upon the surface of a conductor or upon
the surface of the [di-]electric in contact with it?”

He goes on to consider the state of a dielectric substance, such as
glass, when situated between a positively charged and a negatively
charged surface, as in a charged Leyden jar, and argues from analogy
thus:--

“Hence the state of the plate [of glass] under induction is the same
as the state of a magnet, and if split or broken would present new
P[ositive] and N[egative] surfaces before not at all evident.” This
speculation was later verified by Matteucci.

“Probable that phenomena of induction prove more decidedly than
anything else that the electricity is in the [di-]electric not in the
conductor.”

He still worked for a week or two on fluorine, interposing some
experiments on the temperature-limit of magnetisation, but on December
4th decides not to go on with fluorine at present. Then, beginning on
December 5th, there follow twenty-nine pages of the laboratory diary,
illustrated with sketches. He had borrowed from a Mr. Kipp a large
deep copper pan thirty-five inches in diameter, and he set to work
electrifying it and exploring the distribution of the charges, inside
and out, and the inductive effect on objects placed within. Everywhere
he is mentally comparing the distribution of the effects with that of
the flow of currents in an electrolyte. Before many days he writes:--

[Sidenote: PREGNANT SUGGESTIONS.]

“It appears to me at present that _ordinary_ and _electrolytic_
induction are identical in their first nature, but that the latter is
followed by an effect which cannot but from the nature and state of
the substances take place with the former.” Then comes this pregnant
suggestion:--

“Try induction through a solid crystalline body as to the consequent
action on polarized light.”

By the end of a week he had begun to suspect that his magnet analogy
went farther than he was at first prepared to hold. The action of a
magnet was along curved lines of force. So he asks:--

“Can induction through air take place in curves or round a corner--can
probably be found experimentally--if so not a radiating effect.”

After ten days more he has made another step.

“Electricity appears to exist only in _polarity_ as in air, glass,
electrolytes, etc. Now metals, being conductors, cannot take up that
polar state of their own power, or rather retain it, and hence probably
cannot retain developed electric forces.

       *       *       *       *       *

“Metals, however, probably hold it for a moment, as other things do for
a longer time; an end coming at last to all.”

This, it will be observed, is nothing more or less than Clerk Maxwell’s
theory of conduction as being the breaking down of an electrostatic
strain.

In January, 1836, followed the famous experiment of building a
twelve-foot cube, which when electrified exteriorly to the utmost
extent, showed inside no trace of electric forces. The account in the
unpublished MS. of the laboratory book is, as is the case with so
many of these middle-period researches, much fuller than the published
_résumé_ of them in the “Experimental Researches.” All through 1836
he was still at work. Even when on a holiday in the Isle of Wight, in
August, he took his notebook with him, and writes:--

“After much consideration (here at Ryde) of the manner in which the
electric forces are arranged in the various phenomena generally, I have
come to certain conclusions which I will endeavour to note down without
committing myself to any opinion as to the cause of electricity, _i.e._
as to the nature of the power. If electricity exist independently of
matter, then I think that the hypothesis of one fluid will not stand
against that of two fluids. There are, I think, evidently, what I may
call two elements of power of equal force and acting towards each
other. These may conventionally be represented by oxygen and hydrogen,
which represent them in the voltaic battery. But these powers may be
distinguished only _by direction_, and may be no more separate than the
north and south forces in the elements of a magnetic needle. They may
be the polar points of the forces originally placed in the particles of
matter; and the description of the current as an axis of power which I
have formerly given suggests some similar general impression for the
forces of quiescent electricity. Law of electric tension might do, and
though I shall use the terms positive and negative, by them I merely
mean the termini of such lines.”

Right on until November 30th, 1837, this research was continued. The
summary of this and the succeeding researches of 1838 on the same
subject, drawn up by Professor Tyndall,[45] is at once so masterly
and so impartial that it cannot be bettered. It is therefore here
transcribed without alteration.

[Sidenote: ACTION AT A DISTANCE UNTHINKABLE.]

    His first great paper on frictional electricity was sent to
    the Royal Society on November 30, 1837. We here find him face
    to face with an idea which beset his mind throughout his
    whole subsequent life--the idea of _action at a distance_. It
    perplexed and bewildered him. In his attempts to get rid of
    this perplexity he was often unconsciously rebelling against
    the limitations of the intellect itself. He loved to quote
    Newton upon this point: over and over again he introduces his
    memorable words, “That gravity should be innate, inherent, and
    essential to matter, so that one body may act upon another
    at a distance through a _vacuum_ and without the mediation
    of anything else, by and through which this action and force
    may be conveyed from one to another, is to me so great an
    absurdity, that I believe no man who has in philosophical
    matters a competent faculty of thinking can ever fall into it.
    Gravity must be caused by an agent acting constantly according
    to certain laws; but whether this agent be material or
    immaterial I have left to the consideration of my readers.”[46]

    Faraday does not see the same difficulty in his contiguous
    particles. And yet by transferring the conception from masses
    to particles we simply lessen size and distance, but we do not
    alter the quality of the conception. Whatever difficulty the
    mind experiences in conceiving of action at sensible distances,
    besets it also when it attempts to conceive of action at
    insensible distances. Still the investigation of the point
    whether electric and magnetic effects were wrought out through
    the intervention of contiguous particles or not, had a physical
    interest altogether apart from the metaphysical difficulty.
    Faraday grapples with the subject experimentally. By simple
    intuition he sees that action at a distance must be exerted in
    straight lines. Gravity, he knows, will not turn a corner, but
    exerts its pull along a right line; hence his aim and effort to
    ascertain whether electric action ever takes place in curved
    lines. This once proved, it would follow that the action is
    carried on _by means of a medium_ surrounding the electrified
    bodies. His experiments in 1837 reduced, in his opinion, this
    point to demonstration. He then found that he could electrify
    by induction an insulated sphere placed completely in the
    shadow of a body which screened it from direct action. He
    pictured the lines of electric force bending round the edges
    of the screen, and reuniting on the other side of it; and he
    proved that in many cases the augmentation of the distance
    between his insulated sphere and the inducing body, instead of
    lessening, increased the charge of the sphere. This he ascribed
    to the coalescence of the lines of electric force at some
    distance behind the screen.

    [Sidenote: SPECIFIC INDUCTIVE CAPACITY.]

    Faraday’s theoretic views on this subject have not received
    general acceptance, but they drove him to experiment, and
    experiment with him was always prolific of results. By suitable
    arrangements he places a metallic sphere in the middle of a
    large hollow sphere, leaving a space of something more than
    half an inch between them. The interior sphere was insulated,
    the external one uninsulated. To the former he communicated a
    definite charge of electricity. It acted by induction upon the
    concave surface of the latter, and he examined how this act of
    induction was affected by placing insulators of various kinds
    between the two spheres. He tried gases, liquids, and solids,
    but the solids alone gave him positive results. He constructed
    two instruments of the foregoing description, equal in size
    and similar in form. The interior sphere of each communicated
    with the external air by a brass stem ending in a knob. The
    apparatus was virtually a Leyden jar, the two coatings of which
    were the two spheres, with a thick and variable insulator
    between them. The amount of charge in each jar was determined
    by bringing a proof-plane into contact with its knob, and
    measuring by a torsion balance the charge taken away. He first
    charged one of his instruments, and then dividing the charge
    with the other, found that when air intervened in both cases,
    the charge was equally divided. But when shell-lac, sulphur,
    or spermaceti was interposed between the two spheres of one
    jar, while air occupied this interval in the other, then he
    found that the instrument occupied by the “solid dielectric”
    took _more than half_ the original charge. A portion of the
    charge was absorbed in the dielectric itself. The electricity
    took time to penetrate the dielectric. Immediately after the
    discharge of the apparatus no trace of electricity was found
    upon its knob. But after a time electricity was found there,
    the charge having gradually returned from the dielectric in
    which it had been lodged. Different insulators possess this
    power of permitting the charge to enter them in different
    degrees. Faraday figured their particles as polarised, and
    he concluded that the force of induction is propagated from
    particle to particle of the dielectric from the inner sphere
    to the outer one. This power of propagation possessed by
    insulators he calls their “_Specific Inductive Capacity_.”

    [Illustration: FIG. 14.]

    Faraday visualises with the utmost clearness the state of his
    contiguous particles; one after another they become charged,
    each succeeding particle depending for its charge upon its
    predecessor. And now he seeks to break down the wall of
    partition between conductors and insulators. “Can we not,” he
    says, “by a gradual chain of association carry up discharge
    from its occurrence in air through spermaceti and water to
    solutions, and then on to chlorides, oxides, and metals,
    without any essential change in its character?” Even copper, he
    urges, offers a resistance to the transmission of electricity.
    The action of its particles differs from those of an insulator
    only in degree. They are charged like the particles of the
    insulator, but they discharge with greater ease and rapidity;
    and this rapidity of molecular discharge is what we call
    conduction. Conduction, then, is always preceded by atomic
    induction; and when through some quality of the body, which
    Faraday does not define, the atomic discharge is rendered slow
    and difficult, conduction passes into insulation.

    Though they are often obscure, a fine vein of philosophic
    thought runs through these investigations. The mind of the
    philosopher dwells amid those agencies which underlie the
    visible phenomena of induction and conduction; and he tries by
    the strong light of his imagination to see the very molecules
    of his dielectrics. It would, however, be easy to criticise
    these researches, easy to show the looseness, and sometimes
    the inaccuracy, of the phraseology employed; but this critical
    spirit will get little good out of Faraday. Rather let those
    who ponder his works seek to realise the object he set before
    him, not permitting his occasional vagueness to interfere
    with their appreciation of his speculations. We may see the
    ripples, and eddies, and vortices of a flowing stream, without
    being able to resolve all these motions into their constituent
    elements; and so it sometimes strikes me that Faraday clearly
    saw the play of fluids and ethers and atoms, though his
    previous training did not enable him to resolve what he saw
    into its constituents, or describe it in a manner satisfactory
    to a mind versed in mechanics. And then again occur, I
    confess, dark sayings, difficult to be understood, which
    disturb my confidence in this conclusion. It must, however,
    always be remembered that he works at the very boundaries of
    our knowledge, and that his mind habitually dwells in the
    “boundless contiguity of shade” by which that knowledge is
    surrounded.

    [Sidenote: CABLE RETARDATION PREDICTED.]

    In the researches now under review the ratio of speculation and
    reasoning to experiment is far higher than in any of Faraday’s
    previous works. Amid much that is entangled and dark we have
    flashes of wondrous insight and utterances which seem less
    the product of reasoning than of revelation. I will confine
    myself here to one example of this divining power:--By his
    most ingenious device of a rapidly rotating mirror, Wheatstone
    had proved that electricity required time to pass through
    a wire, the current reaching the middle of the wire later
    than its two ends. “If,” says Faraday, “the two ends of the
    wire in Professor Wheatstone’s experiments were immediately
    connected with two large insulated metallic surfaces exposed
    to the air, so that the primary act of induction, after
    making the contact for discharge, might be in part removed
    from the internal portion of the wire at the first instance,
    and disposed for the moment on its surface jointly with the
    air and surrounding conductors, then I venture to anticipate
    that the middle spark would be more retarded than before. And
    if those two plates were the inner and outer coatings of a
    large jar or Leyden battery, then the retardation of the spark
    would be much greater.” This was only a _prediction_, for the
    experiment was not made. Sixteen years subsequently, however,
    the proper conditions came into play, and Faraday was able to
    show that the observations of Werner Siemens and Latimer Clark
    on subterraneous and submarine wires were illustrations, on a
    grand scale, of the principle which he had enunciated in 1838.
    The wires and the surrounding water act as a Leyden jar, and
    the retardation of the current predicted by Faraday manifests
    itself in every message sent by such cables.

    The meaning of Faraday in these memoirs on induction and
    conduction is, as I have said, by no means always clear;
    and the difficulty will be most felt by those who are best
    trained in ordinary theoretic conceptions. He does not know
    the reader’s needs, and he therefore does not meet them. For
    instance, he speaks over and over again of the impossibility
    of charging a body with one electricity, though the
    impossibility is by no means evident. The key to the difficulty
    is this. He looks upon every insulated conductor as the inner
    coating of a Leyden jar. An insulated sphere in the middle of
    a room is to his mind such a coating; the walls are the outer
    coating, while the air between both is the insulator, across
    which the charge acts by induction. Without this reaction of
    the walls upon the sphere, you could no more, according to
    Faraday, charge it with electricity than you could charge a
    Leyden jar, if its outer coating were removed. Distance with
    him is immaterial. His strength as a generaliser enables him
    to dissolve the idea of magnitude; and if you abolish the
    walls of the room--even the earth itself--he would make the
    sun and planets the outer coating of his jar. I dare not
    contend that Faraday in these memoirs made all these theoretic
    positions good. But a pure vein of philosophy runs through
    these writings; while his experiments and reasonings on the
    forms and phenomena of electrical discharge are of imperishable
    importance.

In another part of the twelfth memoir, not included in the above
summary, Faraday deals with the disruptive discharge, and with the
nature of the spark under varying conditions. This is continued on into
the thirteenth memoir, read February, 1838, and is extended to the
cases of “brush” and “glow” discharges. He discovered the existence of
the very remarkable phenomenon of the “dark” discharge near the cathode
in rarefied air. He sought to correlate _all_ the various forms of
discharge, as showing the essential nature of an electric current. “If
a ball be electrified positively,” he says, “in the middle of a room,
and be then moved in any direction, effects will be produced, as if
a _current_ in the same direction (to use the conventional mode of
expression) had existed.” This is the theory of convection currents
later adopted by Maxwell, and verified by experiment by Rowland in 1876.

[Sidenote: COINAGE OF NEW WORDS.]

In the course of this research on induction, Faraday had, as we have
seen, been compelled to adopt new ideas, and therefore to adopt new
names to denote them. The term _dielectric_ for the medium in or across
which the electric forces operate was one of these. As in previous
cases, he consulted with his friends as to suitable terms. In this
instance the following letter from Whewell explains itself. The letter
to which it is a reply has not been preserved, but the reference to
Faraday’s objection to the word _current_ may be elucidated by a
comparison with what Faraday wrote in criticism of that word on pages
146 and 212.

    [_Rev. W. Whewell to M. Faraday._]

                              TRIN. COLL., CAMBRIDGE, _Oct. 14, 1837_.

    MY DEAR SIR,--I am always glad to hear of the progress of
    your researches, and never the less so because they require
    the fabrication of a new word or two. Such a coinage has
    always taken place at the great epochs of discovery; like the
    medals that are struck at the beginning of a new reign:--or
    rather like the change of currency produced by the accession
    of a new sovereign; for their value and influence consists in
    their coming into common circulation. I am not sure that I
    understand the views which you are at present bringing into
    shape sufficiently well to suggest any such terms as you think
    you want. I think that if I could have a quarter of an hour’s
    talk with you I should probably be able to construct terms
    that would record your new notions, so far as I could be made
    to understand them better than I can by means of letters: for
    it is difficult without question and discussion to catch the
    precise kind of relation which you want to express. However,
    by way of beginning such a discussion, I would ask you whether
    you want abstract terms to denote the different and related
    conditions of the body which exercises and the body which
    suffers induction? For though both are active and both passive
    it may still be convenient to suppose a certain ascendancy on
    one side. If so would two such words as _inductricity_ and
    _inducteity_ answer your purpose? They are not very monstrous
    in their form; and are sufficiently distinct. And if you
    want the corresponding adjectives you may call the one the
    _inductric_, and the other the _inducteous_ body. This last
    word is rather a startling one; but if such relations are to
    be expressed, terminations are a good artifice, as we see in
    chemistry: and I have no doubt if you give the world facts
    and laws which are better expressed with than without such
    solecisms, they will soon accommodate to the phrases, as they
    have often done to worse ones. But I am rather in the dark
    as to whether this is the kind of relation which you want to
    indicate. If not, the attempt may perhaps serve to shew you
    where my dulness lies. I do not see my way any better as to the
    other terms, for I do not catch your objection to _current_,
    which appears to me to be capable of jogging on very well
    from _cathode_ to _anode_, or vice versa. As for positive and
    negative, I do not see why _cathodic_ and _anodic_ should not
    be used, if they will do the service you want of them.

    I expect to be in London at the end of the month, and could
    probably see you for half an hour on the 1st of November, say
    at 10, 11, or 12. But in the mean time I shall be glad to hear
    from you whether you can make anything of such conundrums as I
    have mentioned, and am always yours very truly,

                                        W. WHEWELL.

  M. FARADAY Esq^{re.}
      Royal Institution.


[Sidenote: LATERAL ACTIONS OF CURRENT.]

The concluding part of the thirteenth memoir, in which these new
terms are used, is an exceedingly striking speculation on the lateral
or transverse effects of the current. In calling special attention
to them, he says: “I refer of course to the magnetic action and its
relations; but though this is the only recognised lateral action of
the current, there is great reason for believing that others exist and
would by their discovery reward a close search for them.” He seems to
have had an instinctive perception of something that eluded his grasp.
Not until after Maxwell had given mathematical form to Faraday’s own
suggestions was this vision to be realised. He is dimly aware that
there appears to be a lateral tension or repulsion possessed by the
lines of electric inductive action; and onward runs his thought in free
speculation:--

    When current or discharge occurs between two bodies, previously
    under inductrical relations to each other, the lines of
    inductive force will weaken and fade away, and, as their
    lateral repulsive tension diminishes, will contract and
    ultimately disappear in the line of discharge. May not this be
    an effect identical with the attractions of similar currents?
    _i.e._ may not the passage of static electricity into current
    electricity, and that of the lateral tension of the lines of
    the inductive force into the lateral attraction of lines of
    similar discharge, have the same relation and dependences, and
    run parallel to each other?

Series fourteen of the memoirs is on the nature of the electric
force and on the relation of the electric and magnetic forces, and
comprises an inconclusive inquiry as to a possible relation between
specific inductive capacity and axes of crystallisation in crystalline
dielectrics--a relation later assumed as true by Maxwell even before
it was demonstrated by Von Boltzmann. In this memoir, too, occurs a
description of a simple but effective induction balance. Then he asks
what happens to insulating substances, such as air or sulphur, when
they are put in a place where the magnetic forces are varying; they
ought, he thinks, to undergo some state or condition corresponding
to the state that causes currents in metals and conductors, and,
further, that state ought to be one of _tension_. “I have,” he says,
“by rotating non-conducting bodies near magnetic poles, and poles near
them, and also by causing powerful electric currents to be suddenly
formed and to cease around and about insulators in various directions,
endeavoured to make some such state sensible, but have not succeeded.”
In short, he was looking for direct evidence of the existence of what
Maxwell called “displacement currents”--evidence which was later found
independently by the author and by Röntgen. And, again, there rises in
his mind a perception of that _electrotonic state_ which had haunted
his earlier researches as a something imposed upon the surrounding
medium during the growth or dying of an electric current.

[Sidenote: INCESSANT ACTIVITIES.]

In these years (1835–1838) Faraday was still indefatigable in his
lecture duties. In 1835 he gave four Friday discourses, and in May
and June eight afternoon lectures at the Royal Institution on the
metals; also a course of fourteen lectures on electricity to the
medical students at St. George’s Hospital. In 1836 he published
in the _Philosophical Magazine_ a paper on the magnetism of the
metals--notable as containing the still unverified speculation that all
metals would become magnetic in the same way as iron if only cooled to
a sufficiently low temperature--and three other papers, including one
on the “passive” state of iron. He gave four Friday discourses and six
afternoon lectures on heat. In 1837 also four Friday night discourses
and six afternoon lectures were delivered. In 1838 three Friday
discourses and eight afternoon lectures on electricity, ending in June
with a distinct enunciation of the doctrine of the transformations of
“force” (_i.e._ energy) and its indestructibility, afforded evidence of
his industry in this respect. At the same time he was giving scientific
advice to the authorities of Trinity House as to their lighthouses.

The laboratory notebook for March to August, 1838, shows a long
research, occupying nearly 100 folio pages, on the relation of specific
inductive capacity to crystalline structure. This is followed by some
experiments upon an electric eel, at the Royal Adelaide Gallery,
with some unpublished sketches of the distribution in the water of
the currents it emits. He proved, with great satisfaction, that the
currents it gave were capable of producing magnetic effects, sparks,
and chemical decomposition. These observations were embodied in the
fifteenth series of memoirs.

One entry in the laboratory book, of date April 5th, 1838, is of great
interest, as showing how his mind ever recurred to the possibility of
finding a connection between optical and electric phenomena: “Must
try polarized light across a crystalline dielectric under charge. Good
reasons perhaps now evident why a non-crystalline dielectric should
have no effect.”

Faraday was now feeling greatly the strain of all these years of work,
and in 1839 did little research until the autumn. Then he returned to
the question of the origin of the electromotive force of the voltaic
cell, and by the end of the year completed two long papers on this
vexed question; they formed the sixteenth and seventeenth series, and
conclude the memoirs of this second period.

[Sidenote: THE CONTACT THEORY OF ELECTRICITY.]

In the eighth series, completed in April, 1834, on the “Electricity of
the Voltaic Pile,” Faraday had dealt with the question--at that time a
topic of excited controversy--of the origin of the electromotive force
in a cell, Volta, who knew nothing of the chemical actions, ascribed
it to the contact of dissimilar metals, whilst Wollaston, Becquerel,
and De la Rive considered it the result of chemical actions. The
controversy has long ceased to interest the scientific world; for,
with the recognition of the principle of the conservation of energy,
it became evident that mere contact cannot provide a continuing supply
of energy. It would now be altogether dead but for the survival of a
belief in the contact theory on the part of one of the most honoured
veterans in science. But in the years 1834 to 1840 it was of absorbing
interest. Faraday’s work quietly removed the props which supported the
older theory, and it crumbled away. He found that the chemical and
electrical effects in the cell were proportional one to the other, and
inseparable. He discovered a way of making a cell without any metallic
contacts. He showed that without chemical action there was no current
produced. But his results were ignored for the time. After six years
Faraday reopened the question. Again the admirable summary of Professor
Tyndall is drawn upon for the following account:--

    The memoir on the “Electricity of the Voltaic Pile,” published
    in 1834, appears to have produced but little impression upon
    the supporters of the contact theory. These indeed were men
    of too great intellectual weight and insight lightly to take
    up, or lightly to abandon, a theory. Faraday therefore resumed
    the attack in two papers communicated to the Royal Society on
    February 6 and March 19, 1840. In these papers he hampered
    his antagonists by a crowd of adverse experiments. He hung
    difficulty after difficulty about the neck of the contact
    theory, until in its efforts to escape from his assaults it so
    changed its character as to become a thing totally different
    from the theory proposed by Volta. The more persistently it was
    defended, however, the more clearly did it show itself to be
    a congeries of devices, bearing the stamp of dialectic skill
    rather than that of natural truth.

    In conclusion, Faraday brought to bear upon it an argument
    which, had its full weight and purport been understood at
    the time, would have instantly decided the controversy. “The
    contact theory,” he urged, “assumes that a force which is able
    to overcome powerful resistance, as for instance that of the
    conductors, good or bad, through which the current passes,
    and that again of the electrolytic action where bodies are
    decomposed by it, _can arise out of nothing_; that without
    any change in the acting matter, or the consumption of any
    generating force, a current shall be produced which shall go
    on for ever against a constant resistance, or only be stopped,
    as in the voltaic trough, by the ruins which its exertion has
    heaped up in its own course. This would indeed be _a creation
    of power_, and is like no other force in nature. We have many
    processes by which the _form_ of the power may be so changed,
    that an apparent _conversion_ of one into the other takes
    place. So we can change chemical force into the electric
    current, or the current into chemical force. The beautiful
    experiments of Seebeck and Peltier show the convertibility of
    heat and electricity; and others by Oersted and myself show
    the convertibility of electricity and magnetism. _But in no
    case, not even in those of the gymnotus and torpedo, is there a
    pure creation or a production of power without a corresponding
    exhaustion of something to supply it._”

In 1839 Faraday gave five Friday discourses and a course of eight
afternoon lectures on the non-metallic elements. In 1840 he gave
three Friday discourses and seven lectures on chemical affinity. But
in the summer came the serious breakdown alluded to on page 75. He
did no experimental work after September 14th, nor indeed for nearly
two years. Even then it was only a temporary return to research to
investigate the source of the electrification produced by steam in the
remarkable experiments of Mr. (afterwards Lord) Armstrong. He proved it
to be due to friction. This done, he continued to rest from research
until the middle of 1844, though he lectured a little for the Royal
Institution. In 1841 he gave the juvenile lectures. In 1842 he gave
two Friday discourses, one of them being on the lateral discharge in
lightning-rods. He also gave the Christmas lectures on electricity.

[Sidenote: END OF SECOND ACTIVE PERIOD.]

In 1843 he gave three Friday discourses, one of which was on the
electricity generated by a jet of steam; and repeated the eight
afternoon lectures he had given in 1838. In 1844 he gave eight lectures
on heat and two Friday discourses. He also resumed research on the
condensation of gases, and vainly tried to liquefy oxygen and hydrogen,
though he succeeded with ammonia and nitrous oxide.

During these years of rest he also did a little work for Trinity House,
chiefly concerning lighthouses and their ventilation.




CHAPTER V.

SCIENTIFIC RESEARCHES: THIRD PERIOD.


Throughout the fruitful ten years of Faraday’s middle period two
magistral ideas had slowly grown up in his mind, and as he let his
thought play about the objects of his daily activities, these ideas
possessed and dominated him as no newly suggested idea could have done.
They were the correlation and inter-convertibility of the forces of
nature, and the optical relations of magnetism and electricity.

During the period of enforced rest, from 1839 to 1844, these ideas had
been ever with him. His was a mind which during times of quiet brooding
did not cease to advance. In silence his thoughts arranged themselves
in readiness for the next period of activity, and his work, when it
began again, was all the more fruitful for the antecedent period of
cogitation.

[Sidenote: OPTICAL ANALYSIS.]

On August 30th, 1845, Faraday for the sixth time set to work in his
laboratory to search for the connection between light and electricity
for which he had so often looked, and about which he had so boldly
speculated. He began by looking for some effect to be produced on
polarised light by passing it through a liquid which was undergoing
electrolysis. What effect precisely he expected to observe is unknown.
Doubtless he had an open mind to perceive effects of any kind had such
occurred. Earlier in the century the phenomena of polarised light had
been worked out in great detail, through a host of beautiful phenomena,
by Arago, Biot, Brewster, and others; and their discoveries had shown
that this agent is capable of revealing in transparent substances
details of structure which otherwise would be quite invisible. Placed
between two Nicol prisms or two slices of tourmaline, to serve
respectively as “polariser” and “analyser,” thin sheets of transparent
crystal--selenite or mica--were made to reveal the fact that they
possessed an axis of maximum elasticity. For when the analyser and
polariser were set in the “crossed” position, where the one would cut
off all the luminous vibrations that the other would transmit, no light
would be visible to the observer, unless in the intervening space there
were interposed some substance endowed with one of two properties,
either that of resolving some part of the vibrations into an oblique
direction or else that of rotating the plane of the vibrations to right
or to left. If either of these things is done, light appears through
the analyser. It is thus that structure is observed in horn and in
starch grains. It is thus that the strains in a piece of compressed
glass are made visible. It is thus that crystalline structures
generally can be studied. It is thus that the discovery was made of the
substances which possess the strange property of twisting or rotating
the plane of polarisation of light--namely, quartz crystal, solutions
of sugar and of certain alkaloids, and certain other liquids, such
as turpentine. Such was the agent which Faraday proposed to employ to
detect whether electric forces impress any quality resembling that of
_structure_ upon transparent materials.

The notes begin with the words:--

“I have had a glass trough made 24 inches long, 1 inch wide and
about 1½ deep, in which to decompose electrolites and, whilst under
decomposition, along which I could pass a ray of light in different
conditions and afterwards examine it.”

He put into this trough two platinum electrodes and a solution of
sulphate of soda, but could find no effects. Eight pages of the
notebook are filled with details all leading to negative results. For
ten days he worked at these experiments with liquid electrolytes.
The substances used were distilled water, solution of sugar, dilute
sulphuric acid, solution of sulphate of soda (using platinum
electrodes), and solution of sulphate of copper (using copper
electrodes). The current was sent along the ray, and perpendicular
to it in two directions at right angles with each other. The ray
was made to rotate, by altering the position of the polariser (in
this case a black-glass mirror at the proper angle), so that the
plane of polarisation might be varied. The current was used as a
continuous current, as a rapidly intermitting current, and as a rapidly
alternating induction current; _but in no case was any trace of action
perceived_.

[Sidenote: A DIFFICULT RESEARCH.]

Then he turned to solid dielectrics to see if under electric strain
they would yield any optical effect. He had indeed so far back as
1838 tried the experiment of coating two opposite faces of a glass
cube with metal foil plates that were then electrified by a powerful
electric machine. But the experiment had no result. This experiment
he now repeats with a score of elaborate variations, trying both
crystalline and non-crystalline dielectrics. Rock-crystal, Iceland
spar, flint glass, heavy-glass, turpentine, and air, had a beam of
polarised light passed through them, and at the same time “lines of
electrostatic tension” were, by means of the coatings, Leyden jars,
and the electric machine, directed across these bodies, both parallel
to the polarised ray and across it, both in and across the plane of
polarisation; but again without any visible effect. Then he tries on
the same bodies, and on water, the “tension” of a rapidly alternating
induced current, but still with the same negative result. Professor
Tyndall stated that from conversation with Faraday, and with his
faithful assistant Anderson, he inferred that the labour expended on
this preliminary and apparently fruitless research was very great.
It occupies many pages of the laboratory notebook. That thirty-two
years later Dr. Kerr succeeded in finding this optical effect of
electrostatic strain for which Faraday vainly sought, is no reflection
upon Faraday’s powers of observation. Had there been no Faraday there
had doubtless been no discovery by Kerr.

So far the quest had been carried on either with electric currents
flowing through the transparent substance or else with mere statical
electric forces, and a whole fortnight had been spent without result.
Now another track is taken, and it leads straight to success. He
substitutes magnetic for electric forces.

[Sidenote: MAGNETO-OPTIC DISCOVERY.]

“13th Sept. 1845.

[Illustration: FIG. 15.]

“To-day worked with lines of magnetic force, passing them across
different bodies transparent in different directions, and at the same
time passing a polarized ray of light through them, and afterwards
examining the ray by a Nichol’s Eye-piece or other means. The magnets
were Electro-magnets one being our large cylinder Electro-magnet and
the other a temporary iron core put into the helix on a frame. This was
not nearly so strong as the former. The current of 5 cells of Grove’s
battery was sent through both helices at once and the magnets were
made and unmade by putting in or stopping off the electric current.”
Air, flint-glass, rock-crystal, calcareous spar, were examined, but
without effect. And so he worked on through the morning, trying first
one specimen, then another, altering the directions of the poles of
his magnets, reversing their polarity, changing the position of his
optical apparatus, increasing the battery-power of his magnetising
current. Then he bethinks him of that “heavy-glass”--the boro-silicate
of lead--which had cost him nearly four years of precious labour during
the first period of his scientific life. The entry in the notebook is
characteristic.

[Illustration: FIG. 16.]

“A piece of heavy glass, which was 2 inches by 1·8 inches and 0·5 of
an inch thick, being a silico-borate of lead, was experimented with.
It gave no effects when the _same magnetic poles_ or the _contrary_
poles were on opposite sides (as respects the course of the polarised
ray);--nor when the same poles were on the same side either with the
constant or intermitting current; =BUT= when contrary magnetic poles
were on the same side there _was an effect produced on the polarised
ray_, and thus magnetic force and light were proved to have relations
to each other. This fact will most likely prove exceedingly fertile,
and of great value in the investigation of conditions of natural force.

“The effect was of this kind. The glass, a result of one of my old
experiments on optical glass, had been exceedingly well annealed
so that it did not in any degree affect the polarized ray. The two
magnetic poles were in a horizontal plane, and the piece of glass put
up flat against them so that the polarized ray could pass through its
edges and be examined by the eye at a Nicholl’s eye piece. In its
natural state the glass had no effect on the polarized ray but on
making contact at the battery so as to render the cores N and S magnets
instantly the glass acquired a certain degree of _power of depolarizing
the ray_ which it retained steadily as long as the cores were magnets
but which it lost the instant the electric current was stopped. Hence
it was a permanent condition and as was expected did not sensibly
appear with an intermitting current.

[Illustration: FIG. 17.]

“The effect was not influenced by any jogging motion or any moderate
pressure of the hands on the glass.

“The heavy glass had tinfoil coatings on its two sides but when these
were taken off the effect remained exactly the same.

“A mass of soft iron on the outside of the _heavy glass_ greatly
_diminished_ the effect [see Fig. 17]....

“All this shews that it is when the _polarized ray_ passes _parallel_
to the _lines of magnetic induction_ or rather to the _direction of
the magnetic curves_, that the glass manifests its power of affecting
the ray. So that the heavy glass in its magnetized state corresponds to
the cube of rock crystal: the direction of the magnetic curves in the
piece of glass corresponding to the direction of the optic axis in the
crystal (see Exp. Researches 1689–1698)....

[Illustration: FIG. 18.]

“Employed our large _ring electro-magnet_ which is very powerful and
has of course the poles in the right [position] only they are very
close not more than [0·5] of an inch apart. When the _heavy glass_ was
put up against it the effect was produced better than in any former
case....

[Sidenote: ENOUGH FOR TO-DAY.]

“Have got enough for to-day.”

The description which he published in the “Researches” of the first
successful experiment is as follows:--

“A piece of this glass about 2 inches square and 0·5 of an inch thick,
having flat and polished edges, was placed as a _diamagnetic_[47]
between the poles (not as yet magnetized by the electric current),
so that the polarized ray should pass through its length; the glass
acted as air, water, or any other indifferent substance would do; and
if the eye-piece [_i.e._ analyzer] were previously turned into such a
position that the polarized ray was extinguished, or rather the image
produced by it rendered invisible, then the introduction of this glass
made no alteration in that respect. In this state of circumstances
the force of the electromagnet was developed, by sending an electric
current through its coils, and immediately the image of the lamp-flame
became visible, and continued so as long as the arrangement continued
magnetic. On stopping the electric current, and so causing the magnetic
force to cease, the light instantly disappeared; these phænomena could
be renewed at pleasure, at any instant of time, and upon any occasion,
showing a perfect dependence of cause and effect.”

He paused for four days in order to procure more powerful
electromagnets, for the effect which he had observed was exceedingly
slight: “A person looking for the phænomenon for the first time would
not be able to see it with a weak magnet.”

The entry in the notebook begins again:--

“18th Sept. 1845.

“Have now borrowed and received the Woolwich magnet.”

[Sidenote: AN EXCELLENT DAY’S WORK.]

This was a more powerful electromagnet than that at the Institution.
With this he sets to work with such energy that twelve pages of the
laboratory book are filled in one day. His thoughts had ripened during
the five days, and he advanced rapidly from point to point. The first
experiment with the Woolwich magnet brings out another point, of which
at once he grasped the significance:--

“Heavy Glass (original, or 174[48]) when placed thus produced a very
fine effect. The brightness of the image produced rose gradually not
instantly, due to this that the iron cores do not take their full
intensity of magnetic state at once but require time, and so the
magnetic curves rise in intensity. In this way the effect is one by
which an optical examination of the electromagnet can be made--and the
time necessary clearly shewn.”

He next ascertains definitely that the phenomenon is one of rotatory
polarisation--that is to say, the action of the magnet is to twist and
rotate the plane of polarisation through a definite angle depending on
the strength of the magnet and the direction of the exciting current.
He finds the direction of the rotation, and verifies it by comparison
with the ordinary optical rotation produced by turpentine and by a
solution of sugar, winding up with the words:--

“_An excellent day’s work._”

For four days he went on accumulating proofs, and now succeeding with
the very substances with which he formerly failed. On September 26th
he tried the conjoint effect of a magnetic and an electric field.
He also tried the effect of a current running along a transparent
liquid electrolytically whilst the magnet was in operation. The only
results appeared to be those due to the magnet alone. For six days in
October the experiments were continued. He noted, as a desideratum, a
transparent oxide of iron. “With some degree of curiosity and hope” he
“put gold leaf into the magnetic lines, but could perceive no effect.”
He was instinctively looking for the phenomenon which Kundt later
discovered as a property of thin transparent films of iron. He entered
amongst the speculative suggestions in his notebook the query: “Does
this [magnetic] force tend to make iron and oxide of iron transparent?”
On October 3rd he tried experiments on light reflected from the surface
of metals placed in the magnetic field. He indeed obtained an optical
rotation by reflection at the surface of a polished steel button, but
the results were inconclusive owing to imperfection of the surface. It
was reserved for Dr. Kerr to rediscover and follow up this effect. On
October 6th he looked for mechanical and magnetic effects on pieces
of heavy-glass and on liquids in glass bulbs placed between the poles
of his magnet, but found none. He also looked for possible effects of
rapid motion given to the diamagnetic while jointly subject to the
action of magnetism and the light, but found none.

[Sidenote: UNFULFILLED EXPECTATIONS.]

On October 11th he thinks he has got hold of another new fact when
experimenting on liquids in a long glass tube, the record of it
filling three pages. But two days afterwards he finds it only a
disturbing effect due to the communication of heat to the liquid
from the surrounding magnetising coil. He seems to regret the loss
of the new fact, but adds: “As to the other phenomenon of circular
polarization, that comes out constant, clear, and beautiful.”

Then, with that idea of the correlation of forces always in his
head, there recurs to him the notion that if magnetism or electric
currents can affect a beam of light, there must be some sort of
converse phenomenon, and that in some way or other light must be able
to electrify or to magnetise. Thirty-one years before, when visiting
Rome with Davy, he had witnessed the experiments of Morichini on the
alleged magnetic effect of violet light, and had remained unconvinced.
His own idea is very different. And October 14th being a bright day
with good sunlight, he makes the attempt. Selecting a very sensitive
galvanometer, he connects it to a spiral of wire 1 inch in diameter,
4·2 inches long, of 56 convolutions, and then directs a beam of
sunlight along its axis. He tries letting the beam pass alternately
through the coil while the outside is covered, and then along the
exterior while the interior is shaded. But still there is no effect.
Then he inserts an unmagnetised steel bar within the coil, and rotates
it while it is exposed to the sun’s rays. Still there is no effect,
and the sun goes down on another of the unfulfilled expectations. But
had he lived to learn of the effect of light in altering the electric
resistance of selenium discovered by Mayhew, of the photoelectric
currents discovered by Becquerel, of the discharging action of
ultra-violet light discovered by Hertz, of the revivifying effect of
light on recently demagnetised iron discovered by Bidwell, he would
have rejoiced that such other correlations should have been found,
though different from that which he sought. On November 3rd he receives
a new horseshoe magnet, with which he hoped to find some optical effect
on air and other gases, but again without result. That the magnetism of
the earth does actually rotate the plane of polarisation of sky light
was the discovery of Henri Becquerel so late as 1878.

Faithful to his own maxim: “Work, finish, publish,” Faraday lost no
time in writing out his research. It was presented to the Royal Society
on November 6th, but the main result was verbally mentioned on November
3rd at the monthly meeting of the Royal Institution, and reported in
the _Athenæum_ of November 8th, 1845.

But even before the memoir was thus given to the world another
discovery had been made. For on November 4th with the new magnet he
repeated an experiment which a month previously had been without
result. So preoccupied was he over the new event that he did not even
go to the meeting of the Royal Society on November 20th, when his paper
on the “Action of Magnets on Light” was read. What that new discovery
was is well told by Faraday himself in the letter which he sent to
Professor A. de la Rive on December 4th:--

[Sidenote: FRESH MAGNETIC DISCOVERY.]

    [_Faraday to Professor Aug. de la Rive._]

                                        Brighton, December 4, 1845.

    MY DEAR FRIEND,-- * * * I count upon you as one of those whose
    free hearts have pleasure in my success, and I am very grateful
    to you for it. I have had your last letter by me on my desk
    for several weeks, intending to answer it; but absolutely I
    have not been able, for of late I have shut myself up in my
    laboratory and wrought, to the exclusion of everything else. I
    heard afterwards that even your brother had called on one of
    these days and been excluded.

    Well, a part of this result is that which you have heard,
    and my paper was read to the Royal Society, I believe, last
    Thursday, for I was not there; and I also understand there have
    been notices in the _Athenæum_, but I have not had time to see
    them, and I do not know how they are done. However, I can refer
    you to the _Times_ of last Saturday (November 29th) for a very
    good abstract of the paper. I do not know who put it in, but it
    is well done, though brief. To that account, therefore, I will
    refer you.

    For I am still so involved in discovery that I have hardly
    time for my meals, and am here at Brighton both to refresh
    and work my head at once, and I feel that unless I had been
    here, and been careful, I could not have continued my labours.
    The consequence has been that last Monday I announced to our
    members at the Royal Institution another discovery, of which I
    will give you the pith in a few words. The paper will go to the
    Royal Society next week, and probably be read as shortly after
    as they can there find it convenient.

    Many years ago I worked upon optical glass, and made a vitreous
    compound of silica, boracic acid, and lead, which I will
    now call heavy glass, and which Amici uses in some of his
    microscopes; and it was this substance which enabled me first
    to act on light by magnetic and electric forces. Now, if a
    square bar of this substance, about half an inch thick and
    two inches long, be very freely suspended between the poles
    of a powerful horse-shoe electro-magnet, immediately that
    the magnetic force is developed, the bar points; but it does
    not point from pole to pole, but equatorially or across the
    magnetic lines of force--_i.e._ east and west in respect of
    the north and south poles. If it be moved from this position
    it returns to it, and this continues as long as the magnetic
    force is in action. This effect is the result of a still
    simpler action of the magnet on the bar than what appears by
    the experiment, and which may be obtained at a single magnetic
    pole. For if a cubical or rounded piece of the glass be
    suspended by a fine thread six or eight feet long, and allowed
    to hang very near a strong magneto-electric pole (not as yet
    made active), then on rendering the pole magnetic the glass
    will be repelled, and continue repelled until the magnetism
    ceases. This effect or power I have worked out through a great
    number of its forms and strange consequences, and they will
    occupy two series of the “Experimental Researches.” It belongs
    to _all matter_ (not magnetic, as iron) without exception,
    so that every substance belongs to the one or the other
    class--magnetic or diamagnetic bodies. The law of action in
    its simple form is that such matter tends to go from strong to
    weak points of magnetic force, and in doing this the substance
    will go in either direction along the magnetic curves, or in
    either direction across them. It is curious that amongst the
    metals are found bodies possessing this property in as high a
    degree as perhaps any other substance. In fact, I do not know
    at present whether heavy glass, or bismuth, or phosphorus is
    the most striking in this respect. I have very little doubt
    that you have an electro-magnet strong enough to enable you to
    verify the chief facts of pointing equatorially and repulsion,
    if you will use bismuth carefully examined as to its freedom
    from magnetism, and making of it a bar an inch and a half long,
    and one-third or one-fourth of an inch wide. Let me, however,
    ask the favour of your keeping this fact to yourself for two
    or three weeks, and preserving the date of this letter as a
    record. I ought (in order to preserve the respect due to the
    Royal Society) not to write a description to anyone until the
    paper has been received or even read there. After three weeks
    or a month I think you may use it, guarding, as I am sure you
    will do, my right. And now, my dear friend, I must conclude,
    and hasten to work again. But first give my kindest respects to
    Madame de la Rive, and many thanks to your brother for his call.

    Ever your obedient and affectionate friend,

                                        M. FARADAY.


[Sidenote: MAGNETIC EXPERIMENTS.]

The discovery of diamagnetism which Faraday thus announced was in
itself a notable achievement. As Tyndall points out, the discovery
itself was in all probability due to Faraday’s habit of not regarding
as final any negative result of an experiment until he had brought to
bear upon it the most powerful resources at his command. He had tried
the effects of ordinary magnets on brass and copper and other materials
commonly considered as non-magnetic. But when, for the purpose of
the preceding research on the relation of magnetism to light, he had
deliberately procured electromagnets of unusual power, he again tried
what their effect might be upon non-magnetic stuffs. Suspending a piece
of his heavy glass near the poles in a stirrup of writing-paper slung
upon the end of a long thread of cocoon silk, he found it to experience
a strong mechanical action when the magnet was stimulated by turning on
the current. His precision of description is characteristic:--

    I shall have such frequent occasion to refer to two chief
    positions of position across the magnetic field, that, to
    avoid periphrasis, I will here ask leave to use a term or two
    conditionally. One of these directions is that from pole to
    pole, or along the lines of magnetic force, I will call it the
    axial direction; the other is the direction perpendicular to
    this, and across the line of magnetic force and for the time,
    and as respects the space between the poles, I will call it the
    _equatorial_ direction.

Note the occurrence in the above passage for the first time of the term
“the magnetic field.” Faraday’s description of the discovery continues
as follows:--

    The bar of silicated borate of lead or heavy glass already
    described as the substance in which magnetic forces were first
    made effectually to bear on a ray of light, and which is 2
    inches long, and about 0·5 inch wide and thick, was suspended
    centrally between the magnetic poles, and left until the effect
    of torsion was over. The magnet was then thrown into action
    by making contact at the voltaic battery. Immediately the bar
    moved, turning round its point of suspension, into a position
    across the magnetic curve or line of force, and, after a few
    vibrations, took up its place of rest there. On being displaced
    by hand from this position it returned to it, and this occurred
    many times in succession.

    [Illustration: FIG. 19.]

    Either end of the bar indifferently went to either side of the
    axial line. The determining circumstance was simply inclination
    of the bar one way or the other to the axial line at the
    beginning of the experiment. If a particular or marked end of
    the bar were on one side of the magnetic or axial line when
    the magnet was rendered active, that end went further outwards
    until the bar had taken up the equatorial position....

    Here, then, we have a magnetic bar which points east and
    west in relation to north and south poles--_i.e._ points
    perpendicularly to the lines of magnetic force....

    [Sidenote: DIAMAGNETIC LAWS.]

    To produce these effects of pointing across the magnetic
    curves, the form of the heavy glass must be long. A cube or
    a fragment approaching roundness in form will not point, but
    a long piece will. Two or three rounded pieces or cubes,
    placed side by side in a paper tray, so as to form an oblong
    accumulation, will also point.

    Portions, however, of any form are _repelled_; so if two pieces
    be hung up at once in the axial line, one near each pole, they
    are repelled by their respective poles, and approach, seeming
    to attract each other. Or if two pieces be hung up in the
    equatorial line, one on each side of the axis, then they both
    recede from the axis, seeming to repel each other.

    From the little that has been said, it is evident that the
    bar presents in its motion a complicated result of the force
    exerted by the magnetic power over the heavy glass, and that
    when cubes or spheres are employed a much simpler indication of
    the effect may be obtained. Accordingly, when a cube was thus
    used with the two poles, the effect was repulsion or recession
    from either pole, and also recession from the magnetic axis on
    either side.

    So the indicating particle would move either along the magnetic
    curves or across them, and it would do this either in one
    direction or the other, the only constant point being that its
    tendency was to move from stronger to weaker places of magnetic
    force.

    This appeared much more simply in the case of a single magnetic
    pole, for then the tendency of the indicating cube or sphere
    was to move outwards in the direction of the magnetic lines
    of force. The appearance was remarkably like a case of weak
    electric repulsion.

    The cause of the pointing of the bar, or any oblong arrangement
    of the heavy glass, is now evident. It is merely a result of
    the tendency of the particles to move outwards, or into the
    positions of weakest magnetic action.

       *       *       *       *       *

    When the bar of heavy glass is immersed in water, alcohol,
    or æther, contained in a vessel between the poles, all the
    preceding effects occur--the bar points and the cube recedes
    exactly in the same manner as in air.

    The effects equally occur in vessels of wood, stone, earth,
    copper, lead, silver, or any of those substances which belong
    to the diamagnetic class.

    I have obtained the same equatorial direction and motions of
    the heavy glass bar as those just described, but in a very
    feeble degree, by the use of a good common steel horseshoe
    magnet.

Then he goes on to enumerate the many bodies of all sorts: crystals,
powders, liquids, acids, oils; organic bodies such as wax, olive-oil,
wood, beef (fresh and dry), blood, apple, and bread, all of which were
found to be diamagnetic. On this he remarks:--

    It is curious to see such a list as this of bodies presenting
    on a sudden this remarkable property, and it is strange to find
    a piece of wood, or beef, or apple, obedient to or repelled by
    a magnet. If a man could be suspended with sufficient delicacy
    after the manner of Dufay, and placed in the magnetic field, he
    would point equatorially, for all the substances of which he is
    formed, including the blood, possess this property.

[Sidenote: THE MAGNETIC BRAKE.]

A few bodies were found to be feebly magnetic, including paper,
sealing-wax, china ink, asbestos, fluorspar, peroxide of lead,
tourmaline, plumbago, and charcoal. As to the metals, he found iron,
cobalt, and nickel to stand in a distinct class. A feeble magnetic
action in platinum, palladium, and titanium was suspected to be due
to traces of iron in them. Bismuth proved to be the most strongly
diamagnetic, and was specially studied. The repellent effect between
bismuth and a magnet had indeed been casually observed twice in the
prior history of science, first by Brugmans, then by Le Baillif.
Faraday, with characteristic frankness, refers to his having a “vague
impression” that the repulsion of bismuth by a magnet had been
observed before, though unable at the time of writing to recollect any
reference. His own experiments ran over the whole range of substances,
however, and demonstrated the universal existence in greater or less
degree of this magnetic nature. Certain differences observed between
the behaviour of bismuth and of heavy glass on the one hand, and
of copper on the other hand, though all are diamagnetic, led him
to note and describe some of the pseudo-diamagnetic effects which
occur in copper and silver, in consequence of the induction in them
of eddy-currents, from which heavy-glass and bismuth are, by their
inferior electric conductivity, comparatively free. He described the
beautiful and now classical experiment of arresting, by turning on the
exciting current, the rotation of a copper cylinder spinning between
the poles of an electromagnet.

Faraday continued to prosecute this newest line of research, and at
the end of December, 1845, presented another memoir (the twenty-first
series of the Experimental Researches) to the Royal Society. He had now
examined the salts of iron, and had found that every salt and compound
containing iron in the basic part was magnetic, both in the solid
and in the liquid state. Even prussian-blue and green bottle-glass
were magnetic. The solutions of the salts of iron were of special
importance, since they furnish the means of making a magnet which
is for the time liquid, transparent, and, within certain limits,
adjustable in strength. His next step was to examine how bodies
behaved when immersed in some surrounding medium. A weak solution of
iron, enclosed in a very thin glass tube, though it pointed axially
when hung in air, pointed equatorially when immersed in a stronger
solution. A tube full of air pointed axially, and was attracted as
if magnetic when surrounded with water. Substances such as bismuth,
copper, and phosphorus are, however, highly diamagnetic when suspended
_in vacuo_. Such a view would make _mere space_ magnetic. Hence Faraday
inclined at first to the opinion that diamagnetics had a specific
action antithetically distinct from ordinary magnetic action. Several
times he pointed out that all the phenomena resolve themselves simply
into this, that a portion of such matter as is termed diamagnetic
tends to move from stronger to places or points of weaker force in
the magnetic field. He does, indeed, hazard the suggestion that the
phenomena might be explained on the assumption that there was a sort of
diamagnetic polarity--that magnetic induction caused in them a contrary
state to that which it produced in ordinary magnetic matter. But his
own experiments failed to support this view, and, in opposition to
Weber and Tyndall, he maintained afterwards the non-polar nature of
diamagnetic action.

In 1846 Faraday gave two Friday night discourses on these magnetic
researches, one on the cohesive force of water, and one on Wheatstone’s
electromagnetic chronoscope. At the conclusion of the last-named he
said that he was induced to utter a speculation which had long been
gaining strength in his mind, that perhaps those vibrations by which
radiant energies, such as light, heat, actinic rays, etc., convey
their force through space are not mere vibrations of an æther, but of
the lines of force which, in his view, connect different masses, and
so was inclined, in his own phrase, “to dismiss the æther.” In one of
his other discourses he made the suggestion that we might “perhaps
hereafter obtain magnetism from light.”

[Sidenote: THOUGHTS ON RAY VIBRATIONS.]

The speculation above referred to is of such intrinsic importance, in
view of the developments of the last decade, that it compels further
notice. Faraday himself further expanded it in a letter to Richard
Phillips, which was printed in the _Philosophical Magazine_ for May,
1846, under the title “Thoughts on Ray-vibrations.” In this avowedly
speculative paper Faraday touched the highest point in his scientific
writings, and threw out, though in a tentative and fragmentary way,
brilliant hints of that which his imagination had perceived, as in
a vision;--the doctrine now known as the electromagnetic theory of
light. At the dates when the earlier biographies of Faraday appeared,
neither that doctrine nor this paper had received the recognition due
to its importance. Tyndall dismisses it as “one of the most singular
speculations that ever emanated from a scientific man.” Bence Jones
just mentions it in half a line. Dr. Gladstone does not allude to it.
It therefore seems expedient to give here some extracts from the letter
itself:--

    THOUGHTS ON RAY-VIBRATIONS.

  _To Richard Phillips, Esq._

    DEAR SIR,--At your request, I will endeavour to convey to you a
    notion of that which I ventured to say at the close of the last
    Friday evening meeting ...; but, from first to last, understand
    that I merely threw out, as matter for speculation, the vague
    impressions of my mind, for I gave nothing as the result of
    sufficient consideration, or as the settled conviction, or even
    probable conclusion at which I had arrived.

    The point intended to be set forth for the consideration
    of the hearers was whether it was not possible that the
    vibrations--which in a certain theory are assumed to account
    for radiation and radiant phenomena--may not occur in the lines
    of force which connect particles, and consequently masses, of
    matter together--a notion which, as far as it is admitted, will
    dispense with the æther, which, in another view, is supposed to
    be the medium in which these vibrations take place.

       *       *       *       *       *

    Another consideration bearing conjointly on the hypothetical
    view, both of matter and radiation, arises from the comparison
    of the velocities with which the radiant action and certain
    powers of matter are transmitted. The velocity of light through
    space is about 190,000 miles[49] a second. The velocity of
    electricity is, by the experiments of Wheatstone, shown to be
    as great as this, if not greater. The light is supposed to be
    transmitted by vibrations through an æther which is, so to
    speak, destitute of gravitation, but infinite in elasticity;
    the electricity is transmitted through a small metallic wire,
    and is often viewed as transmitted by vibrations also. That
    the electric transference depends on the forces or powers of
    the matter of the wire can hardly be doubted when we consider
    the different conductibility of the various metallic and
    other bodies, the means of affecting it by heat or cold, the
    way in which conducting bodies by combination enter into the
    constitution of non-conducting substances, and the contrary,
    and the actual existence of one elementary body (carbon)
    both in the conducting and non-conducting state. The power
    of electric conduction, being a transmission of force equal
    in velocity to that of light, appears to be tied up in and
    dependent upon the properties of the matter, and is, as it
    were, existent in them.

       *       *       *       *       *

    [Sidenote: LATERAL VIBRATIONS.]

    [Illustration: FIG. 20.]

    In experimental philosophy we can, by the phenomena presented,
    recognise various kinds of lines of force. Thus there are the
    lines of gravitating force, those of electrostatic induction,
    those of magnetic action, and others partaking of a dynamic
    character might be perhaps included. The lines of electric
    and magnetic action are by many considered as exerted through
    space like the lines of gravitating force. For my own part, I
    incline to believe that when there are intervening particles
    of matter--being themselves only centres of force--they take
    part in carrying on the force through the line, but that when
    there are none the line proceeds through space. Whatever the
    view adopted respecting them may be, we can, at all events,
    affect these lines of force in a manner which may be conceived
    as partaking of the nature of a shake or lateral vibration.
    For suppose two bodies, A B, distant from each other, and
    under mutual action,[50] and therefore connected by lines of
    force, and let us fix our attention upon one resultant of force
    having an invariable direction as regards space; if one of
    the bodies move in the least degree right or left, or if its
    power be shifted for a moment within the mass (neither of these
    cases being difficult to realise if A or B be either electric
    or magnetic bodies), then an effect equivalent to a lateral
    disturbance will take place in the resultant upon which we are
    fixing our attention, for either it will increase in force
    whilst the neighbouring resultants are diminishing, or it will
    fall in force while they are increasing.

       *       *       *       *       *

    The view which I am so bold as to put forth considers,
    therefore, radiation as a high species of vibration in the
    lines of force which are known to connect particles, and also
    masses, of matter together. It endeavours to dismiss the æther,
    but not the vibrations. The kind of vibration which, I believe,
    can alone account for the wonderful, varied, and beautiful
    phenomena of polarisation is not the same as that which occurs
    on the surface of disturbed water or the waves of sound in
    gases or liquids, for the vibrations in these cases are direct,
    or to and from the centre of action, whereas the former are
    lateral. It seems to me that the resultant of two or more lines
    of force is in an apt condition for that action, which may be
    considered as equivalent to a _lateral_ vibration; whereas a
    uniform medium like the æther does not appear apt, or more apt
    than air or water.

    The occurrence of a change at one end of a line of force easily
    suggests a consequent change at the other. The propagation of
    light, and therefore probably of all radiant action, occupies
    _time_; and that a vibration of the line of force should
    account for the phenomena of radiation, it is necessary that
    such vibration should occupy time also.

       *       *       *       *       *

    [Sidenote: THE SHADOW OF A SPECULATION.]

    And now, my dear Phillips I must conclude. I do not think I
    should have allowed these notions to have escaped from me had
    I not been led unawares, and without previous consideration,
    by the circumstances of the evening on which I had to appear
    suddenly[51] and occupy the place of another. Now that I have
    put them on paper, I feel that I ought to have kept them much
    longer for study, consideration, and perhaps final rejection;
    and it is only because they are sure to go abroad in one
    way or another, in consequence of their utterance on that
    evening, that I give them a shape, if shape it may be called,
    in this reply to your inquiry. One thing is certain, that any
    hypothetical view of radiation which is likely to be received
    or retained as satisfactory must not much longer comprehend
    alone certain phenomena of light, but must include those of
    heat and of actinic influence also, and even the conjoined
    phenomena of sensible heat and chemical power produced by
    them. In this respect a view which is in some degree founded
    upon the ordinary forces of matter may perhaps find a little
    consideration amongst the other views that will probably
    arise. I think it likely that I have made many mistakes in the
    preceding pages, for even to myself my ideas on this point
    appear only as the shadow of a speculation, or as one of those
    impressions on the mind which are allowable for a time as
    guides to thought and research. He who labours in experimental
    inquiries knows how numerous these are, and how often their
    apparent fitness and beauty vanish before the progress and
    development of real, natural truth.

                                        I am, my dear Phillips,
                                              Ever truly yours,
                                                        M. FARADAY.

  _Royal Institution_,
      _April 15, 1846_.


If it be thought that too high a value has here been set upon a
document which its author himself only claimed to be “the shadow of
a speculation,” let that value be justified out of the mouth of the
man who eighteen years later enriched the world with the mathematical
theory of the propagation of electric waves, the late Professor Clerk
Maxwell. In 1864 he published in the _Philosophical Transactions_ a
“Dynamical Theory of the Electromagnetic Field,” in which the following
passages occur:--

    We have therefore reason to believe, from the phenomena of
    light and heat, that there is an æthereal medium filling
    space and permeating bodies capable of being set in motion,
    and of transmitting that motion to gross matter, so as to
    heat it and affect it in various ways.... Hence the parts
    of this medium must be so connected that the motion of one
    part depends in some way on the motion of the rest; and at
    the same time these connections must be capable of a certain
    kind of elastic yielding, since the communication of motion
    is not instantaneous, but occupies time. The medium is
    therefore capable of receiving and storing up two kinds of
    energy--namely, the “actual” energy depending on the motion of
    its parts, and “potential” energy, consisting of the work which
    the medium will do in recovering from displacement in virtue of
    its elasticity.

    The propagation of undulations consists in the continual
    transformation of one of these forms of energy into the other
    alternately, and at any instant the amount of energy in the
    whole medium is equally divided, so that half is energy of
    motion and half is elastic resilience.

       *       *       *       *       *

    In order to bring these results within the power of symbolic
    calculation, I then express them in the form of the general
    equations of the electromagnetic field.

       *       *       *       *       *

    The general equations are next applied to the case of a
    magnetic disturbance propagated through a non-conducting field,
    and it is shown that the only disturbances which can be so
    propagated are those which are transverse to the direction
    of propagation, and that the velocity of propagation is
    the velocity _v_, found from experiments such as those of
    Weber, which expresses the number of electrostatic units of
    electricity which are contained in one electromagnetic unit.
    This velocity is so nearly that of light, that it seems we have
    strong reason to conclude that light itself (including radiant
    heat and other radiations, if any) is an electromagnetic
    disturbance in the form of waves propagated through the
    electromagnetic field according to electromagnetic laws....
    Conducting media are shown to absorb such radiations rapidly,
    and therefore to be generally opaque.

    [Sidenote: ELECTROMAGNETIC THEORY OF LIGHT.]

    The conception of the propagation of transverse magnetic
    disturbances to the exclusion of normal ones is distinctly set
    forth by Professor Faraday in his “Thoughts on Ray Vibrations.”
    _The electromagnetic theory of light, as proposed by him, is
    the same in substance as that which I have begun to develop
    in this paper_,[52] except that in 1846 there were no data to
    calculate the velocity of propagation.

During the rest of this year (1846) and the next Faraday did very
little research, though he continued his Royal Institution lectures and
his reports for Trinity House. Amongst the latter in 1847 was one on
a proposal to light buoys by incandescent electric lamps containing a
platinum wire spiral. He was compelled, indeed, to rest by a recurrence
of brain troubles, giddiness, and loss of memory. Honours however,
continued to be heaped upon him both abroad and at home, as the
following extract from Bence Jones shows:--

    In 1846, for his two great discoveries, the Rumford and the
    Royal Medals were both awarded to him. This double honour
    will probably long be unique in the annals of the Royal
    Society. In former years he had already received the Copley
    and Royal Medals for his experimental discoveries. As his
    medals increased it became remarkable that he--who kept his
    diploma-book, his portraits and letters of scientific men, and
    everything he had in the most perfect order--seemed to take
    least care of his most valuable rewards. They were locked up in
    a box, and might have passed for old iron. Probably he thought,
    as others did afterwards, that their value, if seen, might lead
    to their loss.

[Sidenote: CRYSTALLINE FORCES.]

Between the twenty-first and twenty-second series of “Experimental
Researches” nearly three years elapsed. In the autumn of 1848 the
matter which claimed investigation was the peculiar behaviour of
bismuth in the magnetic field. Certain anomalies were observed
which were finally traced to the crystalline nature of the metal,
for it appeared that when in that state the crystals themselves--to
adopt modern phraseology--showed a greater magnetic permeability in
a direction perpendicular to their planes of cleavage than in any
direction parallel to those planes. Hence when a crystalline fragment
was hung in a _uniform_ magnetic field (where the diamagnetic tendency
to move from a strong to a weak region of the field was eliminated),
it tended to point in a determinate direction. Faraday expressed it
that the structure of the crystal showed a certain “axiality,” and he
regarded these effects as presenting evidence of a “magnecrystallic”
force, the law of action being that the line or axis of magnecrystallic
force tended to place itself parallel to the lines of the magnetic
field in which the crystal was placed. Arsenic, antimony, and other
crystalline metals were similarly examined. The subject was an
intricate one, and there are frequent obscurities in the phraseology
tentatively adopted for explaining the phenomena. In one place Faraday
rather pathetically laments his imperfect mathematical knowledge.
This seems like an echo of his inability to follow the analytical
reasoning of Poisson, who, starting from a hypothesis about the
supposed “magnetic fluids” being movable within the particles of a
body, supposing that these particles were non-spherical and were
symmetrically arranged, had predicted (in 1827) that a portion of such
a substance would, when brought into the neighbourhood of a magnet,
act differently, according to the different positions in which it
might be turned about its centre. But this very inability to follow
Poisson’s refined analysis gave a new direction to Faraday’s thoughts,
and caused him to conceive the idea of magnetic permeabilities
differing in different directions, an idea which, as Sir William
Thomson (the present Lord Kelvin) showed in 1851,[53] is equally
susceptible of mathematical treatment by appropriate symbols. Lord
Kelvin has also spoken (_op. cit._, p. 484) of the matter as follows:
“The singular combination of mathematical acuteness with experimental
research and profound physical speculation which Faraday, though not
a ‘mathematician,’ presented is remarkably illustrated by his use of
the expression ‘_conducting power of a magnetic medium for lines of
force_.’” Tyndall has given a succinct summary of these researches--in
which also he took a part--from which the following extract must
suffice:--

    And here follows one of those expressions which characterise
    the conceptions of Faraday in regard to force generally: “It
    appears to me impossible to conceive of the results in any
    other way than by a mutual reaction of the magnetic force, and
    the force of the particles of the crystal upon each other.” He
    proves that the action of the force, though thus molecular,
    is an action at a distance. He shows that a bismuth crystal
    can cause a freely-suspended magnetic needle to set parallel
    to its magnecrystallic axis. Few living men are aware of the
    difficulty of obtaining results like this, or of the delicacy
    necessary to their attainment. “But though it thus takes up the
    character of a force acting at a distance, still it is due to
    that power of the particles which makes them cohere in regular
    order and gives the mass its crystalline aggregation, and so
    often spoken of as acting at _insensible_ distances.” Thus he
    broods over this new force, and looks at it from all points of
    inspection. Experiment follows experiment, as thought follows
    thought. He will not relinquish the subject as long as a hope
    exists of throwing more light upon it. He knows full well the
    anomalous nature of the conclusion to which his experiments
    lead him. But experiment to him is final, and he will not
    shrink from the conclusion. “This force,” he says, “appears to
    me to be very strange and striking in its character. It is not
    polar, for there is no attraction or repulsion.” And then, as
    if startled by his own utterance, he asks: “What is the nature
    of the mechanical force which turns the crystal round and makes
    it affect a magnet?”... “I do not remember,” he continues,
    “heretofore such a case of force as the present one--where
    a body is brought into position only without attraction or
    repulsion.”

    Plücker, the celebrated geometer already mentioned, who pursued
    experimental physics for many years of his life with singular
    devotion and success, visited Faraday in those days, and
    repeated before him his beautiful experiments on magneto-optic
    action. Faraday repeated and verified Plücker’s observations,
    and concluded, what he at first seemed to doubt, that Plücker’s
    results and magnecrystallic action had the same origin.

    [Sidenote: MAGNETISM AND CRYSTALLISATION.]

    At the end of his papers, when he takes a last look along
    the line of research, and then turns his eyes to the future,
    utterances quite as much emotional as scientific escape from
    Faraday. “I cannot,” he says at the end of his first paper on
    magnecrystallic action, “conclude this series of researches
    without remarking how rapidly the knowledge of molecular forces
    grows upon us, and how strikingly every investigation tends
    to develop more and more their importance and their extreme
    attraction as an object of study. A few years ago magnetism was
    to us an occult power, affecting only a few bodies. Now it is
    found to influence all bodies, and to possess the most intimate
    relations with electricity, heat, chemical action, light,
    crystallisation, and through it with the forces concerned in
    cohesion. And we may, in the present state of things, well feel
    urged to continue in our labours, encouraged by the hope of
    bringing it into a bond of union with gravity itself.”

In 1848 Faraday gave five Friday night discourses, three of them on
the “Diamagnetic Condition of Flame and Gases.” In 1849 he gave two,
one of them on Plücker’s researches. In 1850 he gave two, one of them
being on the electricity of the air, the other on certain conditions of
freezing water. He had meanwhile continued to work at magnetism. The
twenty-third series dealt with the supposed diamagnetic polarity. It
incidentally discussed the distortion produced in a magnetic field by
a mass of copper in motion across it. The twenty-fourth series was on
the possible relation of gravity to electricity. The paper concludes
with the words: “Here end my trials for the present. The results are
negative. They do not shake my strong feeling of the existence of a
relation between gravity and electricity, though they give no proof
that such a relation exists.” The next series (the twenty-fifth) was
on the “Non-expansion of Gases by Magnetic Force” and on the “Magnetic
Characters of Oxygen [which he had found to be highly magnetic],
Nitrogen, and Space.” He had found that magnetically substances must be
classed either along with iron and the materials that point axially, or
else with bismuth and those that point equatorially, in the magnetic
field. The best vacuum he could procure he regarded as the zero of
these tests; but before adopting it as such, he verified by experiment
that even in a vacuum a magnetic body still tends from weaker to
stronger places in the magnetic field; while diamagnetic bodies tend
from stronger to weaker. He then says we must consider the magnetic
character and relation of _space_ free from any material substance.
“Mere space cannot act as matter acts, even though the utmost latitude
be allowed to the hypothesis of an ether.” He then proceeds as
follows:--

[Sidenote: MORE NEW WORDS.]

    Now that the true zero is obtained, and the great variety of
    material substances satisfactorily divided into two general
    classes, it appears to me that we want another name for
    the magnetic class, that we may avoid confusion. The word
    _magnetic_ ought to be general, and include _all_ the phenomena
    and effects produced by that power. But then a word for the
    subdivision opposed to the diamagnetic class is necessary.
    As the language of this branch of science may soon require
    general and careful changes, I, assisted by a kind friend, have
    thought that a word--not selected with particular care--might
    be provisionally useful; and as the magnetism of iron, nickel,
    and cobalt when in the magnetic field is like that of the
    earth as a whole, so that when rendered active they place
    themselves parallel to its axes or lines of magnetic force, I
    have supposed that they and their similars (including oxygen
    now) might be called paramagnetic bodies, giving the following
    division:--

                             { paramagnetic
                    Magnetic {
                             { diamagnetic.


The “kind friend” alluded to was Whewell, as the following letter
shows:--

    [_Rev. W. Whewell to M. Faraday._]

                                        July, 1850.

    I am always glad to hear of your wanting new words, because
    the want shows that you are pursuing new thoughts--and your
    new thoughts are worth something--but I always feel also how
    difficult it is for one who has not pursued the train of
    thought to suggest the right word. There are so many relations
    involved in a new discovery, and the word ought not glaringly
    to violate any of them. The purists would certainly object
    to the opposition, or co-ordination, of _ferromagnetic_ and
    _diamagnetic_, not only on account of the want of symmetry
    in the relation of _ferro_ and _dia_, but also because the
    one is Latin and the other Greek.... Hence it would appear
    that the two classes of magnetic bodies are those which place
    their length _parallel_, or _according_, to the terrestrial
    magnetic lines, and those which place their length transverse
    to such lines. Keeping the preposition _dia_ for the latter,
    the preposition _para_, or _ana_, might be used for the former.
    Perhaps para would be best, as the word _parallel_, in which it
    is involved, would be a technical memory for it.... I rejoice
    to hear that you have new views of discovery opening to you. I
    always rejoice to hail the light of such when they dawn upon
    you.

The twenty-sixth series of researches opened with a consideration of
magnetic “conducting power,” or permeability as we should now term
it, and then branched off into a lengthy discussion of atmospheric
magnetism. The subject was continued through the twenty-seventh series,
which was completed in November, 1850. The gist of this is summed up in
one of his letters to Schönbein:--

                              Royal Institution, November 19, 1850.

    MY DEAR SCHÖNBEIN,--I wish I could talk with you, instead of
    being obliged to use pen and paper. I have fifty matters to
    speak about, but either they are too trifling for writing, or
    too important, for what can one discuss or say in a letter?...
    By the bye, I have been working with the oxygen of the air
    also. You remember that three years ago I distinguished it as
    a magnetic gas in my paper on the diamagnetism of flame and
    gases founded on Bancalari’s experiment. Now I find in it the
    cause of all the annual and diurnal, and many of the irregular,
    variations in the terrestrial magnetism. The observations made
    at Hobarton, Toronto, Greenwich, St. Petersburg, Washington,
    St. Helena, the Cape of Good Hope, and Singapore, all appear
    to me to accord with and support my hypothesis. I will not
    pretend to give you an account of it here, for it would require
    some detail, and I really am weary of the subject. I have sent
    in three long papers to the Royal Society, and you shall have
    copies of them in due time....

                    Ever, my dear Schönbein, most truly yours,
                                                       M. FARADAY.


[Sidenote: PAPERS TO BE LET LOOSE.]

While writing out these researches for the Royal Society, he had been
staying in Upper Norwood. He wrote thus of himself to Miss Moore at
the end of August:--

    We have taken a little house here on the hill-top, where I have
    a small room to myself, and have, ever since we came here, been
    deeply immersed in magnetic cogitations. I write, and write,
    and write, until three papers for the Royal Society are nearly
    completed, and I hope that two of them will be good if they
    justify my hopes, for I have to criticise them again and again
    before I let them loose. You shall hear of them at some of the
    Friday evenings. At present I must not say more. After writing,
    I walk out in the evening, hand-in-hand with my dear wife, to
    enjoy the sunset; for to me, who love scenery, of all that I
    have seen or can see there is none surpasses that of Heaven. A
    glorious sunset brings with it a thousand thoughts that delight
    me.

To De la Rive he wrote later as follows:--

    [_M. Faraday to A. de la Rive._]

                              Royal Institution, February 4, 1851.

    MY DEAR DE LA RIVE,--My wife and I were exceedingly sorry to
    hear of your sad loss. It brought vividly to our remembrance
    the time when we were at your house, and you, and others with
    you, made us so welcome. What can we say to these changes but
    that they show by comparison the vanity of all things under the
    sun? I am very glad that you have spirits to return to work
    again, for that is a healthy and proper employment of the mind
    under such circumstances.

    With respect to my views and experiments, I do not think
    that anything shorter than the papers (and they will run
    to a hundred pages in the “Transactions”) will give you
    possession of the subject, because a great deal depends upon
    the comparison of observations in different parts of the world
    with the facts obtained by experiment, and with the deductions
    drawn from them; but I will try to give you an idea of the root
    of the matter. You are aware that I use the phrase _line of
    magnetic force_, to represent the presence of magnetic force,
    and the direction (of polarity) in which it is exerted; and by
    the idea which it conveys one obtains very well, and I believe
    without error, a notion of the distribution of the forces about
    a bar magnet, or between near flat poles presenting a field
    of equal force, or in any other case. Now, if circumstances
    be arranged so as to present a field of equal force, which is
    easily done, as I have shown by the electro-magnet, then if a
    sphere of iron or nickel be placed in the field, it immediately
    disturbs the direction of the lines of force, for they are
    concentrated within the sphere. They are, however, not merely
    concentrated, but _contorted_, for the sum of forces in any
    one section across the field is always equal to the sum of
    forces in any other section, and therefore their condensation
    in the iron or nickel cannot occur without this contortion.
    Moreover, the contortion is easily shown by using a small
    needle (one-tenth of an inch long) to examine the field, for,
    as before the introduction of the sphere of iron or nickel, it
    would always take up a position parallel to itself. Afterwards
    it varies in position in different places near the sphere.
    This being understood, let us then suppose the sphere to be
    raised in temperature. At a certain temperature it begins to
    lose its power of affecting the lines of magnetic force, and
    ends by retaining scarcely any. So that as regards the little
    needle mentioned above, it now stands everywhere parallel to
    itself within the field of force. This change occurs with iron
    at a very high temperature, and is passed through within the
    compass, apparently, of a small number of degrees. With nickel
    it occurs at much lower temperatures, being affected by the
    heat of boiling oil.

    Now take another step. Oxygen, as I showed above, three years
    ago in the _Philosophical Magazine_ for 1847, vol. xxxi.,
    pp. 410, 415, 416, is magnetic in relation to nitrogen and
    other gases. E. Becquerel, without knowing of my results, has
    confirmed and extended them in his paper of last year, and
    given certain excellent measures. In my paper of 1847 I showed
    also that oxygen (like iron and nickel) lost its magnetic power
    and its ability of being attracted by the magnet when heated
    (p. 417). And I further showed that the temperatures at which
    this took place were within the range of common temperature,
    for the oxygen of the air--_i.e._ the air altogether--is
    increased in magnetic power when cooled to 0° F. (p. 406).
    Now I must refer you to the papers themselves for the (to
    me) strange results of the incompressibility (magnetically
    speaking) of oxygen and the inexpansibility of nitrogen and
    other gases; for the description of a differential balance by
    which I can compare gas with gas, or the same gas at different
    degrees of rarefaction; for the determination of the true
    zero, or point between magnetic and diamagnetic bodies; and
    for certain views of magnetic conduction and polarity. You
    will there find described certain very delicate experiments
    upon diamagnetic and very weak magnetic bodies concerning
    their action on each other in a magnetic field of equal force.
    The magnetic bodies repel each other, and the diamagnetic
    bodies repel each other; but a magnetic and a diamagnetic body
    _attract_ each other. And these results, combined with the
    qualities of oxygen as just described, convince me that it is
    able to deflect the lines of magnetic force passing through it
    just as iron or nickel is, but to an infinitely smaller amount,
    and that its power of deflecting the lines varies with its
    temperature and degree of rarefaction.

    [Sidenote: ATMOSPHERIC MAGNETISM.]

    Then comes in the consideration of the atmosphere, and the
    manner in which it rises and falls in temperature by the
    presence and absence of the sun. The place of the great warm
    region nearly in his neighbourhood; of the two colder regions
    which grow up and diminish in the northern and southern
    hemispheres as the sun travels between the tropics; the
    effect of the extra warmth of the northern hemisphere over
    the southern; the effect of accumulation from the action of
    preceding months; the effect of dip and mean declination
    at each particular station; the effects that follow from
    the non-coincidence of magnetic and astronomical conditions
    of polarity, meridians, and so forth; the results of the
    distribution of land and water for any given place--for all
    these and many other things I must refer you to the papers.
    I could not do them justice in any account that a letter
    could contain, and should run the risk of leading you into
    error regarding them. But I may say that, deducing from the
    experiments and the theory what are the deviations of the
    magnetic needle at any given station, which may be expected as
    the mean result of the heating and cooling of the atmosphere
    for a given season and hour, I find such a general accordance
    with the results of observations, especially in the direction
    and generally in the amount for different seasons of the
    _declination_ variation, as to give me the strongest hopes that
    I have assigned the true physical cause of those variations,
    and shown the _modus operandi_ of their production.

    And now, my dear de la Rive, I must leave you and run to other
    matters. As soon as I can send you a copy of the papers I will
    do so, and can only say I hope that they will meet with your
    approbation. With the kindest remembrances to your son,

    Believe me to be, my dear friend, ever truly yours,

                                        M. FARADAY.


This hope of explaining the variations of terrestrial magnetism by
the magnetic properties of the oxygen of the air was destined to be
illusory. At that time the cosmical nature of magnetic storms was
unknown and unsuspected. To this matter we may well apply Faraday’s own
words addressed to Tyndall respecting the alleged diamagnetic polarity,
and the conflict of views between himself on the one hand and Weber and
Tyndall on the other:--“It is not wonderful that views differ at first.
Time will gradually sift and shape them. And I believe that we have
little idea at present of the importance they may have ten or twenty
years hence.”

[Sidenote: LINES OF MAGNETIC FORCE.]

In 1851, from July to December, Faraday was actively at work in the
laboratory. The results constitute the material for the twenty-eighth
and twenty-ninth (the last) series of the “Experimental Researches.”
In these he returned to the subject with which the first series had
opened in 1831: the induction of electric currents by the relative
motion of magnets and conducting wires. These two memoirs, together
with his Royal Institution lecture of January, 1852, “On the Lines of
Magnetic Force,” and the paper “On the Physical Character of the Lines
of Magnetic Force” (which he sent to the _Philosophical Magazine_, as
containing “so much of a speculative and hypothetical nature”), should
be read, and re-read, and read again, by every student of physics.
They are reprinted at the end of the third volume of the “Experimental
Researches.”

In the opening of the twenty-eighth memoir he says:--

    From my earliest experiments on the relation of electricity and
    magnetism, I have had to think and speak of lines of magnetic
    force as representations of the magnetic power--not merely in
    the points of quality and direction, but also in quantity....
    The direction of these lines about and amongst magnets and
    electric currents is easily represented and understood in a
    general manner by the ordinary use of iron filings.

    A point equally important to the definition of these lines
    is, that they represent a determinate and unchanging amount
    of force. Though, therefore, their forms, as they exist
    between two or more centres or sources of power, may vary very
    greatly, and also the space through which they may be traced,
    yet the sum of power contained in any one section of a given
    portion of the lines is exactly equal to the sum of power in
    any other section[54] of the same lines, however altered in
    form or however convergent or divergent they may be at the
    second place.... Now, it appears to me that these lines may
    be employed with great advantage to represent the nature,
    condition, and comparative amount of the magnetic forces,
    and that in many cases they have, to the physical reasoner,
    at least, a superiority over that method which represents
    the forces as concentrated in centres of action, such as the
    poles of magnets or needles; or some other methods, as, for
    instance, that which considers north or south magnetisms as
    fluids diffused over the end, or amongst the particles, of a
    bar. No doubt any of these methods which does not assume too
    much will, with a faithful application, give true results. And
    so they all ought to give the same results, as far as they can
    respectively be applied. But some may, by their very nature, be
    applicable to a far greater extent, and give far more varied
    results, than others. For, just as either geometry or analysis
    may be employed to solve correctly a particular problem, though
    one has far more power and capability, generally speaking, than
    the other; or, just as either the idea of the reflexion of
    images or that of the reverberation of sounds may be used to
    represent certain physical forces and conditions, so may the
    idea of the attractions and repulsions of centres, or that of
    the disposition of magnetic fluids, or that of lines of force,
    be applied in the consideration of magnetic phenomena. It is
    the occasional and more frequent use of the latter which I at
    present wish to advocate.... When the natural truth, and the
    conventional representation of it, most closely agree, then
    are we most advanced in our knowledge. The emission and æther
    theories present such cases in relation to light. The idea
    of a fluid or of two fluids is the same for electricity; and
    there the further idea of a current has been raised, which,
    indeed, has such hold on the mind as occasionally to embarrass
    the science as respects the true character of the physical
    agencies, and may be doing so even now to a degree which we at
    present little suspect. The same is the case with the idea of
    a magnetic fluid or fluids, or with the assumption of magnetic
    centres of action of which the resultants are at the poles.

    [Sidenote: THE FUNCTIONS OF THE ÆTHER.]

    How the magnetic force is transferred through bodies or through
    space we know not--whether the result is merely action at a
    distance, as in the case of gravity, or by some intermediate
    agency, as in the cases of light, heat, the electric current,
    and, as I believe, static electric action. The idea of magnetic
    fluids, as applied by some, or of magnetic centres of action,
    does not include that of the latter kind of transmission,
    but the idea of lines of force does. Nevertheless, because a
    particular method of representing the forces does not include
    such a mode of transmission, the latter is not disproved, and
    that method of representation which harmonises with it may be
    the most true to nature. The general conclusion of philosophers
    seems to be that such cases are by far the most numerous. And
    for my own part, considering the relation of a vacuum to the
    magnetic force, and the general character of magnetic phenomena
    external to the magnet, I am more inclined to the notion that
    in the transmission of the force there is such an action,
    external to the magnet, than that the effects are merely
    attraction and repulsion at a distance. _Such an action may be
    a function of the æther, for it is not at all unlikely that if
    there be an æther, it should have other uses than simply the
    conveyance of radiations._[55]

He then proceeds to recount the experimental evidence of revolving
magnets and loops of wire. Following out the old lines of so moving
the parts of the system that the magnetic lines were “cut” by the
copper conductors, and connecting the latter with a slow-period
galvanometer, to test the resultant induction, he found that “the
_amount_ of magnetic force” [or _flux_, as we should nowadays call it]
“is determinate for the same lines of force, whatever the distance of
the point or plane at which their power is exerted is from the magnet.”
The convergence or divergence of the lines of force caused, _per se_,
no difference in their amount. Obliquity of intersection caused no
difference, provided the same lines of force were cut. If a wire was
moving in a field of equal intensity, and with a uniform motion, then
the current produced was proportional to the velocity of motion. The
“quantity of electricity thrown into a current” was, _ceteris paribus_,
“directly as the amount of curves intersected.” Within the magnet,
running through its substance, existed lines of force of the _same
nature_ as those without, exactly equal in _amount_ to those without,
and were, indeed, _continuous_ with them. The conclusion must logically
be that every line of force is a closed circuit.

Having thus established the exact quantitative laws of magneto-electric
induction, he then advanced to make use of the induced current as a
means of investigating the presence, direction, and amount of magnetic
forces--in other words, to explore and measure magnetic fields. He
constructed revolving rectangles and rings furnished with a simple
commutator, to measure inductively the magnetic forces of the earth.
Then he employed the induced current to test the constancy of magnets
when placed near to other magnets in ways that might affect their
power. Next he considers the fields of magnetic force of two or more
associated magnets, and notes how their magnetic lines may coalesce
when they are so placed as to constitute parts of a common magnetic
circuit. The twenty-ninth series is brought to a close by a discussion
of the experimental way of delineating lines of magnetic force by means
of iron filings.

[Sidenote: THE ELECTROTONIC STATE.]

The paper on the “Physical Character of the Lines of Magnetic Force”
recapitulated the points established in the twenty-ninth series of
“Researches,” and emphasis is laid upon the logical necessity that
time must be required for their propagation. The physical effects
in a magnetic field, as equivalent to a tendency for the magnetic
lines to shorten themselves, and to repel one another laterally, are
considered, and are contrasted with the effects of parallel electric
currents. Commenting on the mutual relation between the directions of
an electric current and of its surrounding magnetic lines, he raises
the question whether or not they consist in a state of tension of the
æther. “Again and again,” he says, “the idea of an _electrotonic_ state
has been forced on my mind. Such a state would coincide and become
identified with that which would then constitute the physical lines
of magnetic force.” Then he traces out the analogy between a magnet,
with its “sphondyloid” (or spindle-form field) of magnetic lines, and
a voltaic battery immersed in water, with its re-entrant lines of flow
of circulating current. Incidentally, while discussing the principle
of the magnetic circuit, he points out that when a magnet is furnished
at its poles with masses of soft iron, it can both receive and retain
a higher magnetic charge than it does without them, “for these masses
carry on the physical lines of force, and deliver them to a body of
surrounding space, which is either widened, and therefore increased, in
the direction across the lines of force, or shortened in that direction
parallel to them, or both; and both are circumstances which facilitate
the conduction from pole to pole.”

[Sidenote: NOVELTY OF FARADAY’S VIEWS.]

Thus closed, with the exception of two fragmentary papers, one on
“Physical Lines of Force,” and the other on “Some Points in Magnetic
Philosophy,” in the years 1853 and 1854 respectively, the main
life-work of Faraday, his “Experimental Researches.” Their effect
in revolutionising electric science, if slow, was yet sure. Though
the principle of the dynamo was discovered and published in 1831,
nearly forty years elapsed before electric-lighting machinery became
a commercial product. Though the dependence of inductive actions,
both electromagnetic and electrostatic, upon the properties of
the intervening medium was demonstrated and elaborated in these
“Researches,” electricians for many years continued to propound
theories which ignored this fundamental fact. French and German writers
continued to publish treatises based on the ancient doctrines of
action at a distance, and of imaginary electric and magnetic fluids.
Von Boltzmann, a typical German of the first rank in science, says
that until there came straight from England the counter-doctrines
amidst which Faraday had lived, “we (in Germany and France) had all
more or less imbibed with our mothers’ milk the ideas of magnetic
and electric fluids acting direct at a distance.” And again, “The
theory of Maxwell”--that is, Faraday’s theory thrown by Maxwell into
mathematical shape--“is so diametrically opposed to the ideas which
have become customary to us, that we must first cast behind us all our
previous views of the nature and operation of electric forces before
we can enter into its portals.” The divergence of view between Faraday
and the Continental electricians is nowhere more clearly stated than
by Faraday’s great interpreter, Maxwell, in the _apologia_ which he
prefixed in 1873 to his “Treatise on Electricity and Magnetism,”
wherein, speaking of the differences between this work and those
recently published in Germany, he wrote:--

    One reason of this is that before I began the study of
    electricity I resolved to read no mathematics on the subject
    till I had first read through Faraday’s “Experimental
    Researches on Electricity.” I was aware that there was supposed
    to be a difference between Faraday’s way of conceiving
    phenomena and that of the mathematicians. So that neither he
    nor they were satisfied with each other’s language. I had also
    the conviction that this discrepancy did not arise from either
    party being wrong. I was first convinced of this by Sir William
    Thomson [Lord Kelvin], to whose advice and assistance, as well
    as to his published papers, I owe most of what I have learned
    on this subject.

    As I proceeded with the study of Faraday, I perceived that his
    method of conceiving the phenomena was also a mathematical one,
    though not exhibited in the conventional form of mathematical
    symbols. I also found that these methods were capable of being
    expressed in the ordinary mathematical forms, and thus compared
    with those of the professed mathematicians.

    For instance, Faraday, in his mind’s eye, saw lines of force
    traversing all space where the mathematicians saw centres of
    force attracting at a distance. Faraday saw a medium where
    they saw nothing but distance. Faraday sought the seat of the
    phenomena in real actions going on in the medium; they were
    satisfied that they had found it in a power of action at a
    distance impressed on electric fluids.

    When I had translated what I considered to be Faraday’s ideas
    into a mathematical form, I found that in general the results
    of the two methods coincided, so that the same phenomena were
    accounted for and the same laws of action deduced by both
    methods, but that Faraday’s methods resembled those in which
    we begin with the whole and arrive at the parts by analysis,
    while the ordinary mathematical methods were founded on the
    principle of beginning with the parts and building up the whole
    by synthesis.

    I found, also, that several of the most fertile methods of
    research discovered by the mathematicians could be expressed
    much better in terms of ideas derived from Faraday than in
    their original form.

    The whole theory, for instance, of potential, considered as
    a quantity which satisfies a certain partial differential
    equation, belongs essentially to the method which I have called
    of Faraday....

    If by anything I have here written I may assist any student
    in understanding Faraday’s modes of thought and expression, I
    shall regard it as the accomplishment of one of my principal
    aims: to communicate to others the same delight which I have
    found myself in reading Faraday’s “Researches.”

Clerk Maxwell may also be credited with the remark that Faraday’s work
had had the result of banishing the term “the electric fluid” into the
limbo of newspaper science.

[Sidenote: ELECTRIC LIGHT IN LIGHTHOUSES.]

Faraday’s work for Trinity House continued during these last years of
research work. He reported on such subjects as adulteration of white
lead, impure oils, Chance’s lenses, lighthouse ventilation, and fog
signals. Two systems of electric arc lighting for lighthouses--one by
Watson, using batteries, the other by Holmes, using a magneto-electric
machine--were examined in 1853 and 1854, but his report on them was
adverse. He “could not put up in a lighthouse what has not been
established beforehand, and is only experimental.” In 1856 he made five
reports, in 1857 six, and in 1858 twelve reports to Trinity House,
one of these being on the electric light at the South Foreland. In
1859 he reported on further trials in which Duboscq’s lamps were used.
In 1860 he gave a final report on the practicability and utility of
magneto-electric lighting, and expressed the hope it would be applied,
as there was _now_ no difficulty. In 1861 he inspected the machinery as
established at the Dungeness lighthouse. In 1862 he gave no fewer than
seventeen reports, visiting Dungeness, Grisnez, and the South Foreland.
In 1863 he again visited Dungeness. In 1864 he made twelve reports, and
examined the drawings and estimates for establishing the electric light
at Portland. His last report was in 1865, upon the St. Bees’ light, and
he then retired from this service.

His Friday night discourses were still continued during these years.
In 1855 he gave one on “Ruhmkorff’s Induction-coil.” In 1856 he gave
one on a process for silvering glass, and on finely divided gold. This
latter subject, the optical properties of precipitated gold, formed
the topic of the Bakerian lecture of that year--his last contribution
to the Royal Society. He gave another discourse on the same subject
in 1857, and also one on the conservation of force. In 1856, when
investigating the crystallisation of water, he discovered the
phenomenon of regelation of ice. In virtue of this property two pieces
of ice will freeze solidly together under pressure, even when the
temperature of the surrounding atmosphere is above the freezing point.
This discovery led on the one hand to the explanation of glacier
motions; on the other to important results in thermodynamic theory. In
1859 he gave two discourses, one on ozone, the other on phosphorescence
and fluorescence. He also gave two in 1860, on lighthouse illumination
by electric light, and on the electric silk-loom. In 1861 he discoursed
on platinum and on De la Rue’s eclipse photographs. The last of his
Friday night discourses was given on June 20th, 1862. It was on
Siemens’s gas furnaces. He had been down at Swansea watching the
furnaces in operation, and now proposed to describe their principle. It
was rather a sad occasion, for it was but too evident that his powers
were fast waning. Early in the evening he had the misfortune to burn
the notes he had prepared, and became confused. He concluded with a
touching personal explanation how with advancing years his memory had
failed, and that in justice to others he felt it his duty to retire.

At intervals he still attempted to work at research. In 1860 he sent a
paper to the Royal Society on the relations of electricity to gravity,
but, on the advice of Professor (afterwards Sir George) Stokes, it was
withdrawn. He had also in contemplation some experiments upon the time
required in the propagation of magnetism, and began the construction of
a complicated instrument, which was never finished.

[Sidenote: HYPOTHESIS AND EXPERIMENT.]

His very last experiment, as recorded in his laboratory notebook, is
of extraordinary interest, as showing how his mind was still at work
inquiring into the borderland of possible phenomena. It was on March
12th, 1862. He was inquiring into the effect of a magnetic field
upon a beam of light, which he was observing with a spectroscope to
ascertain whether there was any change produced in the refrangibility
of the light. The entry concludes: “Not the slightest effect on the
polarised or unpolarised ray was observed.” The experiment is of the
highest interest in magneto-optics. The effect for which Faraday
looked in vain in 1862 was discovered in 1897 by Zeeman. That Faraday
should have _conceived_ the existence of this obscure relation between
magnetism and light is a striking illustration of the acuteness of
mental vision which he brought to bear. Living and working amongst
the appliances of his laboratory, letting his thoughts play freely
around the phenomena, incessantly framing hypotheses to account for the
facts, and as incessantly testing his hypotheses by the touchstone of
experiment, never hesitating to push to their logical conclusion the
ideas suggested by experiment, however widely they might seem to lead
from the accepted modes of thought, he worked on with a scientific
prevision little short of miraculous. His experiments, even those which
at the time seemed unsuccessful, in that they yielded no positive
result, have proved to be a mine of amazing richness. The volumes
of his “Experimental Researches” are a veritable treasure-house of
science.




CHAPTER VI.

MIDDLE AND LATER LIFE.


Although to avoid discontinuity the account of Faraday’s researches has
in the previous chapter been followed to their close in 1862, we must
now return to his middle period of life, when his activities at the
Royal Institution were at their zenith.

[Sidenote: BREAKDOWN OF HEALTH.]

Mention has been made of the serious breakdown of Faraday’s health at
the close of 1839. Dr. Latham, whom he consulted as to his attacks of
giddiness, wrote to Brande:--

                                        Grosvenor Street,
                                            December 1, 1839.

    DEAR BRANDE,--I have been seeing our friend Faraday these two
    or three days, and been looking after his health. I trust he
    has no ailment more than rest of body and mind will get rid
    of. But rest is absolutely necessary for him. Indeed, I think
    it would be hardly prudent for him to lecture again for the
    present. He looks up to his work; but, in truth, he is not fit,
    and if he is pressed he will suddenly break down. When we meet,
    I will talk the matter over with you.

                                        Yours most sincerely,
                                                      P. M. LATHAM.


The advice was taken. He gave up nearly all research work, but tried
to go on with Friday night discourses and afternoon lectures in 1840.
Then came a more serious breakdown, and he rested for nearly four
years, with the exception of the Christmas lectures in 1841 and a few
Friday discourses in 1842 and 1843. This illness caused him great
distress of mind, mainly due to an idea that the physicians did not
understand his condition. When in this state he sometimes set down
pencil notes on scraps of paper to relieve his feelings. One such is
the following:--

    Whereas, according to the declaration of that true man of
    the world Talleyrand, the use of language is to conceal the
    thoughts; this is to declare in the present instance, when I
    say I am not able to bear much talking, it means really, and
    without any mistake, or equivocation, or oblique meaning, or
    implication, or subterfuge, or omission, that I am not able;
    being at present rather weak in the head, and able to work no
    more.

During these times of enforced idleness he used to amuse himself with
games of skill, with paperwork, and with visits to the theatre and to
the Zoological Gardens. Mrs. Faraday left the following note:--

    Michael was one of the earliest members of the Zoological
    Society, and the Gardens were a great resource to him when
    overwrought and distressed in the head. The animals were a
    continual source of interest, and we, or rather I, used to
    talk of the time when we should be able to afford a house
    within _my_ walking distance of the entrance; for I much feared
    he could not continue to live in the Institution with the
    continual calls upon his time and thought; but he always shrank
    from the notion of living away from the R. I.

His niece, Miss Reid, told how fond he was of seeing acrobats,
tumblers, dwarfs and giants; even a Punch and Judy show was an
unfailing source of delight. When travelling in Switzerland, as he did
on several occasions, accompanied by Mrs. Faraday and her brother,
George Barnard, the artist, he kept a journal, which reveals his
simple pleasures and enthusiasms. He is delighted with waterfalls and
avalanches, watches the cowherd collecting his cows and the shepherd
calling the sheep, which followed him, leaving the goats to straggle.
On one such visit (in 1841), in order that he might not be absent on
Sunday from his wife, he walked the whole distance from Leukerbad
to Thun, over the Gemmi--a distance of 45 miles--in one day. At
Interlaken, observing that clout-nail-making was practised as a local
industry, he wrote: “I love a smith’s shop and everything relating to
smithery. My father was a smith.”

[Sidenote: IMPRESSIONS OF LIEBIG.]

In 1844 he was well enough to attend the British Association meeting at
York. Liebig, who had also been there, wrote to him three months later
with some reminiscences. What had struck him most was the tendency
in England to ignore the more purely scientific works and to value
only those with a “practical” bearing. “In Germany it is quite the
contrary. Here, in the eyes of scientific men, no value, or at least
but a trifling one, is placed on the practical results. The enrichment
of science is alone considered worthy of attention.” Liebig further
expressed himself dissatisfied with the meeting at York. He had been
interested to make the acquaintance of so many celebrated men, but it
was, strictly, “a feast given to the geologists, the other sciences
serving only to decorate the table.” Then came a more personal note:--

    Often do my thoughts wander back to the period which I spent in
    England, among the many pleasant hours of which the remembrance
    of those passed with you and your amiable wife is to me always
    the dearest and most agreeable. With the purest pleasure I
    bring to mind my walk with her, in the botanical garden at
    York, when I was afforded a glance of the richness of her mind;
    what a rare treasure you possess in her! The breakfast in
    the little house with Snow Harris, and Graham, and our being
    together at Bishopthorpe, are still fresh in my memory.

If Liebig was disposed to underrate the useful applications of science,
Faraday certainly was not. Though his own research work was carried
on with the single aim of scientific progress; though he himself
never swerved aside into any branch research that might have yielded
money; yet he was ever ready to examine, and even to lecture upon,
the inventions of others. He accepted for the subjects of his Friday
night discourses all sorts of topics--artificial stone, machinery for
pen-making, lithography, Ruhmkorff’s induction coil, a process for
silvering mirrors, and lighthouse illumination by electric light. His
very last lecture was on Siemens’s gas-furnaces. He could be just as
enthusiastic over the invention of another as over some discovery of
his own. With respect to his lecture on the Ruhmkorff coil, Tyndall
describes him in a passage which is interesting, as containing an
epithet since adopted for another great man for whom Tyndall had less
respect than for Faraday:--

    I well remember the ecstasy and surprise of _the grand old
    man_, evoked by effects which we should now deem utterly
    insignificant.

Bence Jones says:--

    When he brought the discoveries of others before his hearers,
    one object, and one alone, seemed to determine all he said and
    did, and that was, “without commendation and without censure,”
    to do the utmost that could be done for the discoverer.

In so perfect a character it would be marvellous if there were not
some flaw. His persistent ignoring of Sturgeon, and his attribution
of the invention of the electromagnet to Moll and Henry, whose work
was frankly based on Sturgeon’s, is simply inexplicable. He failed to
appreciate the greatness of Dalton, and thought him an overrated man.

[Sidenote: PERSONAL CHARACTERISTICS.]

Amid all his overflowing kindliness of heart, Faraday preserved other
less obvious traits of character. Any act of injustice or meanness
called forth an almost volcanic burst of indignation. Hot flashes
of temper, fierce moments of wrath were by no means unknown. But he
exercised a most admirable self-control, and a habitual discipline
of soul that kept his temper under. Grim and forbidding, and even
exacting he could show himself to an idle or unfaithful servant. There
were those who feared as well as those who loved and admired him.
Dr. Gladstone says of him that he was no “model of all the virtues,”
dreadfully uninteresting, and discouraging to those who feel calm
perfection out of their reach. “His inner life was a battle, with its
wounds as well as its victory.” “It is true also,” he adds, “that
with his great caution and his repugnance to moral evil, he was more
disposed to turn away in disgust from an erring companion than to
endeavour to reclaim him.”

For thirty years Faraday was the foremost of lecturers on science
in London. From the first occasion when, in 1823, as Sir Roderick
Murchison narrates, he was called upon unexpectedly to act as
substitute for Professor Brande at one of his morning lectures at the
Royal Institution (then held in the subterranean laboratory), down to
the time of his latest appearance as a lecturer in 1862, he was without
a rival as the exponent of natural science.

As no man could achieve and retain such a position without possessing
both natural gifts and appropriate training, it is fitting to inquire
what were those gifts and what the training which were so happily
united in him.

    I was (he said) a very lively, imaginative person, and could
    believe in the Arabian Nights as easily as in the Encyclopædia;
    but facts were important to me, and saved me. I could trust a
    fact, and always cross-examined an assertion.

From the very first Faraday had an appreciation of the way in which
public lectures should be given. In his notes of Davy’s fourth lecture
of April, 1812, he wrote:--

    During the whole of these observations his delivery was easy,
    his diction elegant, his tone good, and his sentiments sublime.

His own first lecture was given in the kitchen of Abbott’s house, with
home-made apparatus placed on the kitchen table. To Abbott, after
only a few weeks of experience at the Royal Institution, he wrote the
letters upon lectures and lecturers, to which allusion was made on p.
15. These show a most remarkably sound perception of the material and
mental furniture requisite for success. From the third and fourth of
them are culled the following excerpts:--

[Sidenote: QUALIFICATIONS OF A LECTURER.]

    The most prominent requisite to a lecturer, though perhaps
    not really the most important, is a good delivery; for though
    to all true philosophers science and nature will have charms
    innumerable in every dress, yet I am sorry to say that the
    generality of mankind cannot accompany us one short hour
    unless the path is strewed with flowers. In order, therefore,
    to gain the attention of an audience (and what can be more
    disagreeable to a lecturer than the want of it?), it is
    necessary to pay some attention to the manner of expression.
    The utterance should not be rapid and hurried, and consequently
    unintelligible, but slow and deliberate, conveying ideas with
    ease from the lecturer, and infusing them with clearness and
    readiness into the minds of the audience. A lecturer should
    endeavour by all means to obtain a facility of utterance, and
    the power of clothing his thoughts and ideas in language smooth
    and harmonious, and at the same time simple and easy.

    With respect to the action of the lecturer, it is requisite
    that he should have some, though it does not here bear the
    importance that it does in other branches of oratory; for
    though I know of no species of delivery (divinity excepted)
    that requires less motion, yet I would by no means have a
    lecturer glued to the table or screwed on the floor. He must
    by all means appear as a body distinct and separate from the
    things around him, and must have some motion apart from that
    which they possess.

    A lecturer should appear easy and collected, undaunted and
    unconcerned, his thoughts about him, and his mind clear and
    free for the contemplation and description of his subject. His
    action should not be hasty and violent, but slow, easy, and
    natural, consisting principally in changes of the posture of
    the body, in order to avoid the air of stiffness or sameness
    that would otherwise be unavoidable. His whole behaviour
    should evince respect for his audience, and he should in no
    case forget that he is in their presence. No accident that
    does not interfere with their convenience should disturb his
    serenity, or cause variation in his behaviour; he should never,
    if possible, turn his back on them, but should give them full
    reason to believe that all his powers have been exerted for
    their pleasure and instruction.

    Some lecturers choose to express their thoughts
    extemporaneously immediately as they occur to the mind, whilst
    others previously arrange them and draw them forth on paper.
    But although I allow a lecturer to write out his matter, I do
    not approve of his reading it--at least, not as he would a
    quotation or extract.

    A lecturer should exert his utmost effort to gain completely
    the mind and attention of his audience, and irresistibly to
    make them join in his ideas to the end of the subject. He
    should endeavour to raise their interest at the commencement
    of the lecture, and by a series of imperceptible gradations,
    unnoticed by the company, keep it alive as long as the subject
    demands it. A flame should be lighted at the commencement, and
    kept alive with unremitting splendour to the end. For this
    reason I very much disapprove of breaks in a lecture, and where
    they can by any means be avoided they should on no account find
    place.... For the same reason--namely, that the audience should
    not grow tired--I disapprove of long lectures; one hour is long
    enough for anyone. Nor should they be allowed to exceed that
    time.

    A lecturer falls deeply beneath the dignity of his character
    when he descends so low as to angle for claps and asks for
    commendation. Yet have I seen a lecturer even at this point. I
    have heard him causelessly condemn his own powers. I have heard
    him dwell for a length of time on the extreme care and niceness
    that the experiment he will make requires. I have heard him
    hope for indulgence when no indulgence was wanted, and I have
    even heard him declare that the experiment now made cannot
    fail, from its beauty, its correctness, and its application,
    to gain the approbation of all.... I would wish apologies to
    be made as seldom as possible, and generally only when the
    inconvenience extends to the company. I have several times seen
    the attention of by far the greater part of the audience called
    to an error by the apology that followed it.

    ’Tis well, too, when the lecturer has the ready wit and
    the presence of mind to turn any casual circumstance to an
    illustration of his subject. Any particular circumstance that
    has become table-talk for the town, any local advantages or
    disadvantages, any trivial circumstance that may arise in
    company, give great force to illustrations aptly drawn from
    them, and please the audience highly, as they conceive they
    perfectly understand them.

    Apt experiments (to which I have before referred) ought to
    be explained by satisfactory theory, or otherwise we merely
    patch an old coat with new cloth, and the whole [hole] becomes
    worse. If a satisfactory theory can be given, it ought to be
    given. If we doubt a received opinion, let us not leave the
    doubt unnoticed and affirm our own ideas, but state it clearly,
    and lay down also our objections. If the scientific world is
    divided in opinion, state both sides of the question, and let
    each one judge for himself by noticing the most striking and
    forcible circumstances on each side. Then, and then only, shall
    we do justice to the subject, please the audience, and satisfy
    our honour, the honour of a philosopher.

[Sidenote: USE OF CRITICISM.]

One who already had set before himself such high ideals could not
fail at least to attempt to fulfil them. Accordingly, when in 1816 he
began to lecture to the City Philosophical Society, he began to attend
an evening class on elocution conducted by Mr. B. H. Smart, though
the pinch of poverty made it difficult to him to afford the needful
fees. Again, in 1823, previous to taking part in Brande’s laboratory
lectures, he took private lessons in elocution from Smart, at the
rate of half-a-guinea a lesson. After 1827, when he was beginning his
regular courses of lectures in the theatre, he often used to get Mr.
Smart to attend in order to criticise his delivery.

Amongst the rules found in his manuscript notes were the following:--

    Never to repeat a phrase.

    Never to go back to amend.

    If at a loss for a word, not to ch-ch-ch or eh-eh-eh, but to
    stop and wait for it. It soon comes, and the bad habits are
    broken and fluency soon acquired.

    Never doubt a correction given to me by another.

His niece, Miss Reid, who lived from 1830 to 1840 at the Institution
with the Faradays, gave the following amongst her recollections:--

    Mr. Magrath used to come regularly to the morning lectures, for
    the sole purpose of noting down for him any faults of delivery
    or defective pronunciation that could be detected. The list
    was always received with thanks; although his corrections
    were not uniformly adopted, he was encouraged to continue his
    remarks with perfect freedom. In early days he always lectured
    with a card before him with _Slow_ written upon it in distinct
    characters. Sometimes he would overlook it and become too
    rapid; in this case, Anderson had orders to place the card
    before him. Sometimes he had the word _Time_ on a card brought
    forward when the hour was nearly expired.

[Sidenote: AS LECTURER.]

In spite of his recourse to aids in acquiring elocutionary excellence,
his own style remained simple and unspoiled. “His manner,” says Bence
Jones, “was so natural, that the thought of any art in his lecturing
never occurred to anyone. For his Friday discourses, and for his
other set lectures in the theatre, he always made ample preparation
beforehand. His matter was always over-abundant. And, if his
experiments were always successful, this was not solely attributable
to his exceeding skill of hand. For, unrivalled as he was as a
manipulator, in the cases in which he attempted to show complicated
or difficult experiments, that which was to be shown was always well
rehearsed beforehand in the laboratory. He was exceedingly particular
about small and simple illustrations. He never merely _told_ his
hearers about an experiment, but _showed_ it to them, however simple
and well known it might be. To a young lecturer he once remarked: ‘If I
said to my audience, “This stone will fall to the ground if I open my
hand,” I should open my hand and let it fall. Take nothing for granted
as known; inform the eye at the same time as you address the ear.’ He
always endeavoured at the outset to put himself _en rapport_ with his
audience by introducing his subject on its most familiar side, and then
leading on to that which was less familiar. Before the audience became
aware of any transition, they were already assimilating new facts which
were thus brought within their range. Nor did he stay his discourse
upon the enunciation of facts merely. Almost invariably, as his
allotted hour drew towards its close, he gave rein to his imagination.
Those who had begun with him on the lower plane of simple facts and
their correlations were bidden to consider the wider bearings of
scientific principles and their relations to philosophy, to life, or to
ethics. While he never forced a peroration, nor dragged in a quotation
from the poets, his own scientific inspiration, as he outlined some
wide-sweeping speculation or suggestion for future discoveries, amply
supplied the fitting finale. If the rush of his ideas might sometimes
be compared to tearing through a jungle, it at least never degenerated
into sermonising; and never, save when he was physically ill, failed to
arouse an enthusiastic glow of response in his hearers. ‘No attentive
listener,’ says Mrs. Crosse, ‘ever came away from one of Faraday’s
lectures without having the limits of his spiritual vision enlarged, or
without feeling that his imagination had been stimulated to something
beyond the mere expression of physical facts.’”

He was not one who let himself dwell in illusions. When he did well he
was perfectly conscious of the fact, and enjoyed a modest satisfaction.
If he had failed of his best, he was conscious too of that. His
deliberate act in giving up all other lectures at the time when his
brain-troubles were gaining upon him, while retaining the Christmas
lectures to juveniles, was thoroughly characteristic. Of one of his
earlier courses of lectures he himself made--about 1832--the following
note:--

    The eight lectures on the operations of the laboratory at the
    Royal Institution, April, 1828, were not to my mind. There
    does not appear to be that opportunity of fixing the attention
    of the audience by a single clear, consistent, and connected
    chain of reasoning which occurs when a principle (_sic_) or
    one particular application is made.... I do not think the
    operations of the laboratory can be rendered useful and popular
    in lectures....

The matter of these same lectures was, however, the basis of his book
on Chemical Manipulation published in 1827. It went through three
editions, and was reprinted in America. But in 1838 he declined to let
a new edition be issued, as he considered the work out of date.

Besides the note quoted above from the Faraday MS. occurs the
following:--

    The six juvenile lectures given Christmas, 1827, were just what
    they ought to have been, both in matter and manner; but it
    would not answer to give an extended course in the same spirit.

Nineteen times did Faraday give the Christmas lectures. Those on the
Chemistry of a Candle were given more than once; and were the last he
gave, in 1860. They have been published, as were those on the Forces of
Nature. The lectures on Metals he was urged to publish, but declined in
the following terms:--

                              Royal Institution, January 3, 1859.

    DEAR SIR,--Many thanks to both you and Mr. Bentley. Mr.
    Murray made me an unlimited offer like that of Mr. Bentley’s
    many years ago, but for the reasons I am about to give you
    I had to refuse his kindness. He proposed to take them by
    shorthand, and so save me trouble, but I knew that would be a
    thorough failure; even if I cared to give time to the revision
    of the MS., still the lectures without the experiments and
    the vivacity of speaking would fall far behind those in the
    lecture-room as to effect. And then I do not desire to give
    time to them, for money is no temptation to me. In fact, I have
    always loved science more than money; and because my occupation
    is almost entirely personal I cannot afford to get rich. Again
    thanking you and Mr. Bentley, I remain,

                                        Very truly yours,
                                                  M. FARADAY.


[Sidenote: AN INSPIRED CHILD.]

Of his lectures Lady Pollock wrote:--

    He would play with his subject now and then, but very
    delicately; his sport was only just enough to enliven the
    attention. He never suffered an experiment to allure him away
    from his theme. Every touch of his hand was a true illustration
    of his argument.... But his meaning was sometimes beyond the
    conception of those whom he addressed. When, however, he
    lectured to children he was careful to be perfectly distinct,
    and never allowed his ideas to outrun their intelligence. He
    took great delight in talking to them, and easily won their
    confidence. The vivacity of his manner and of his countenance,
    and his pleasant laugh, the frankness of his whole bearing,
    attracted them to him. They felt as if he belonged to them; and
    indeed he sometimes, in his joyous enthusiasm, appeared like an
    inspired child.

    ... His quick sympathies put him so closely in relation with
    the child that he saw with the boy’s new wonder, and looked,
    and most likely felt for the moment, as if he had never seen
    the thing before. Quick feelings, quick movement, quick
    thought, vividness of expression and of perception, belonged to
    him. He came across you like a flash of light, and he seemed
    to leave some of his light with you. His presence was always
    stimulating.--_St. Paul’s Magazine_, June, 1870.

A writer in the _British Quarterly Review_ says:--

    He had the art of making philosophy charming, and this was due
    in no little measure to the fact that to grey-headed wisdom he
    united wonderful juvenility of spirit.... Hilariously boyish
    upon occasion he could be, and those who knew him best knew
    he was never more at home, that he never seemed so pleased,
    as when making an old boy of himself, as he was wont to say,
    lecturing before a juvenile audience at Christmas.

Caroline Fox (in “Memories of Old Friends”), under date June 13th,
1851, wrote in her journal:--

    We went to Faraday’s lecture on “Ozone.” He tried the various
    methods of making ozone which Schönbein had already performed
    in our kitchen, and he did them brilliantly. He was entirely at
    his ease, both with his audience and his chemical apparatus.

In the diary of H. Crabb Robinson is an appreciation of Faraday of some
interest:--

    May 8th, 1840.... Attended Carlyle’s second lecture. It gave
    great satisfaction, for it had uncommon thoughts and was
    delivered with unusual animation.... In the evening heard a
    lecture by Faraday. What a contrast to Carlyle! A perfect
    experimentalist with an intellect so clear. Within his sphere
    _un uomo compito_.

Many references to Faraday’s lectures occur in the life of Sir Richard
Owen (published 1894), chiefly extracted from Mrs. Owen’s diary. Two or
three extracts must suffice:--

    1839, Jan. 8th. At eight o’clock with R. to the Royal
    Institution to hear Faraday lecture on electricity, galvanism,
    and the electric eel. Faraday is the _beau idéal_ of a popular
    lecturer.

    1845, Jan. 31. To Faraday’s lecture at the Royal Institution.
    The largest crowd I have ever seen there. Many gentlemen were
    obliged to come into the ladies’ gallery, as they could not
    get seats elsewhere. After an exceedingly interesting lecture,
    Faraday said he had a few remarks to make on some new reform
    laws for the Institution. These remarks were admirably made,
    and no one could feel offended, although it was a direct
    attack on those gentlemen who helped to render the ladies very
    uncomfortable, sometimes by filling seats, and often front
    seats, in the part intended only for ladies. Wearing a hat in
    the library was one of the delinquencies, likewise sitting in
    the seats reserved for the directors, who were obliged by their
    office and duties to be last in. Mr. Faraday also remarked
    that the formation of two currents caused by certain gentlemen
    rushing upstairs the instant the lecture was over to fetch
    their lady friends was not conducive to the comfort of those
    coming downstairs. Everything taken very well.

    [Sidenote: ROYAL INSTITUTION LECTURES.]

    1849, May 28th. With R. to Royal Institution. We got there just
    before three, and there was a crowded audience as usual to hear
    Faraday’s lecture. The poor man entered and attempted to speak,
    but he was suffering from inflammation or excessive irritation
    of the larynx, and after some painful efforts to speak, a
    general cry arose of “Postpone,” and someone, apparently in
    authority, made a short speech from the gallery. Mr. Faraday
    still wished to try and force his voice, saying he was well
    aware of the difficulty of getting back the carriages, etc.,
    before the time for the lecture had elapsed, to say nothing of
    the disappointment to some; but every moment the cry increased.
    “No, no; you are too valuable to be allowed to injure yourself.
    Postpone, postpone.” Poor Faraday was quite overcome.

The interrupted lecture was resumed after a fortnight’s interval; and
he made up the full number of lectures by giving two extra discourses,
at one of which the Prince Consort was present.

    At another lecture [in 1856] Faraday explained the magnet and
    strength of attraction. He made us all laugh heartily; and when
    he threw a coalscuttle full of coals, a poker, and a pair of
    tongs at the great magnet, and they stuck there, the theatre
    echoed with shouts of laughter.

His friend De la Rive testified in striking terms to Faraday’s power as
a speaker.

    Nothing can give a notion of the charm which he imparted to
    these improvised lectures, in which he knew how to combine
    animated, and often eloquent, language with a judgment and art
    in his experiments which added to the clearness and elegance
    of his exposition. He exerted an actual fascination upon his
    auditors; and when, after having initiated them into the
    mysteries of science, he terminated his lecture, as he was in
    the habit of doing, by rising into regions far above matter,
    space, and time, the emotion which he experienced did not fail
    to communicate itself to those who listened to him, and their
    enthusiasm had no longer any bounds.

Faraday remained all his life a keen observer of other lecturers.
Visiting France in 1845, he went to hear Arago give an astronomical
lecture. “He delivered it in an admirable manner to a crowded
audience,” was his comment.

To the Secretary of the Institution, who in 1846 consulted him
regarding evening lectures, he said:

    I see no objection to evening lectures if you can find a fit
    man to give them. As to popular lectures (which at the same
    time are to be _respectable_ and _sound_), none are more
    difficult to find. Lectures which _really teach_ will never be
    popular; lectures which are popular will never _really teach_.
    They know little of the matter who think science is more
    easily to be taught or learned than A B C; and yet who ever
    learned his A B C without pain and trouble? Still, lectures can
    (generally) inform the mind, and show forth to the attentive
    man what he really has to learn, and in their way are very
    useful, especially to the public. I think they might be useful
    to us now, even if they only gave an answer to those who,
    judging by their own earnest desire to learn, think much of
    them. As to agricultural chemistry, it is no doubt an excellent
    and a popular subject, but I rather suspect that those who know
    least of it think that most is known about it.

[Sidenote: USE OF MODELS AND CARDS.]

His fondness for illustrating obscure points in his lectures by
models has been more than once alluded to. He would improvise these
out of wood, paper, wire, or even out of turnips or potatoes, with
much dexterity of hand. In one of his unpublished manuscripts, dating
about 1826, dealing with the then recently discovered phenomena of
electromagnetism, occurs the following note:--

    It is best for illustration to have a model of the constant
    position which the needle takes across the wire: _le voila_
    (Fig. 21).

    [Illustration: FIG. 21.]

Many such simple models were used in his lectures. He leaned upon them
to aid his defective memory; but they helped his audience quite as much
as they aided him. Reference was made on p. 7 to his use of cards, on
which to jot down notes of thoughts that occurred to him. One such runs
as follows:--

    Remember to do one thing at once.

    Also to finish a thing.

    Also to do a little if I could not do _much_.

    Pique about mathematics in chemists, and resolution to support
    the character of experiment--as better for the mass. Hence
    origin of the title _Exp. researches_.

    Influence of authority. Davy and difficulty of steering between
    _self-sufficiency_ and dependance (_sic_) on others.

    Aim at high things, but not presumptuously.

    Endeavour to succeed--expect not to succeed.

    _Criticise_ one’s own view in every way by experiment--if
    possible, leave no objection to be put by others.

Faraday’s enthusiasm about experimental researches was at times
unrestrained, and always contagious. Dumas describes how Faraday
repeated for him the experimental demonstration of the action of
magnetism on light. Having come to the final experiment, Faraday
rubbed his hands excitedly, while his eyes lit up with fire, and his
animated countenance told the passionate feelings which he brought to
the discovery of scientific truth. On another occasion Plücker, of
Bonn, then on a visit to London, showed Faraday in his own laboratory
the action of a magnet upon the luminous electric discharge in vacuum
tubes. “Faraday danced round them; and as he saw the moving arches of
light, he cried: ‘Oh, to live always in it!’” Once a friend met him
at Eastbourne in the midst of a tremendous storm, rubbing his hands
together gleefully because he had been fortunate enough to see the
lightning strike the church tower. To the Baroness Burdett-Coutts
he once wrote inviting her to see some experiments upon spectrum
analysis in his private room. _The experiments_, he wrote, _will not be
beautiful except to the intelligent_.

Yet another reminiscence is to be found in the Memorials of Joseph
Henry. It relates, probably, to the date of 1837, when Henry visited
Europe.

    Henry loved to dwell on the hours that he and Bache had spent
    in Faraday’s society. I shall never forget Henry’s account of
    his visit to King’s College, London, where Faraday, Wheatstone,
    Daniell, and he had met to try and evolve the electric spark
    from the thermopile. Each in turn attempted it and failed.
    Then came Henry’s turn. He succeeded, calling in the aid of
    his discovery of the effect of a long interpolar wire wrapped
    around a piece of soft iron. Faraday became as wild as a boy,
    and, jumping up, shouted: “Hurrah for the Yankee experiment!”

The following memorandum was found on a slip of paper in Faraday’s
“research drawer”:--

    THE FOUR DEGREES.

    The discoverer of a fact.
    The reconciling of it to known principles.
    Discovery of a fact not reconcilable.
    He who refers all to still more general principles.

                                                        M.F.


[Sidenote: FREEDOM OF SPECULATION.]

Faraday’s mind was of a very individual turn; he could not walk
along the beaten tracks, but must pursue truth wherever it led him.
His dogged tenacity for exact fact was accompanied by a perfect
fearlessness of speculation. He would throw overboard without
hesitation the most deeply-rooted notions if experimental evidence
pointed to newer ideas. He had learned to doubt the idea of _poles_;
so he outgrew the idea of _atoms_, which he considered an arbitrary
conception. Many who heard his bold speculations and his free coinage
of new terms deemed him vague and loose in thought. Nothing could be
more untrue. He let his mind play freely about the facts; he framed
thousands of hypotheses, only to let them go by if they were not
supported by facts. “He is the wisest philosopher,” he said in a
lecture on the nature of matter, “who holds his theory with some
doubt--who is able to proportion his judgment and confidence to the
value of the evidence set before him, taking a fact for a fact and a
supposition for a supposition, as much as possible keeping his mind
free from all source of prejudice; or, where he cannot do this (as in
the case of a theory), remembering that such a source is there.”

In one of his later experimental researches he wrote:--

    As an experimentalist, I feel bound to let experiment guide me
    into any train of thought which it may justify; being satisfied
    that experiment, like analysis, must lead to strict truth if
    rightly interpreted; and believing also that it is in its
    nature far more suggestive of new trains of thought and new
    conditions of natural power.

[Sidenote: WHY NO SUCCESSOR.]

Perhaps it was this very freedom of thought which debarred him from
enlisting other men as collaborators in his researches. His one
assistant for thirty years, Sergeant Anderson, was indeed invaluable
to him for his quality of implicit obedience. Other helpers in the
laboratory he had none. Apparently he found his researches to be of too
individual a character to permit him to deputise any part of his work.
He was never satisfied when told about another’s experiment; he must
perform it for himself. Often a discovery arose from some chance or
trivial incident of an otherwise unsuccessful experiment. The power of
“lateral vision,” which Tyndall has so strongly emphasised, was a prime
factor in his successes. That power could not be delegated to any mere
assistant. Many times did outsiders approach him, thinking to bring new
facts to his notice; never, save on the solitary occasion when a Mr.
William Jenkin drew his attention to the “extra-current” spark seen on
the breaking of an electric circuit, did such novelties turn out to
be really new. Alleged discoveries thus brought to him merely plagued
him. He thought that anyone who had the wit to observe any really new
phenomenon would be the person best qualified to work it out. His
method was to work on alone, dwelling amidst his experiments until the
mind, familiarising itself with the facts, was ready to suggest their
correlations. It was sometimes urged against him as a complaint that he
never took up any younger man to train him as his successor, even as
Davy had taken up himself and trained him in scientific work. One of
the miscellaneous notes, found after his death, throws some light on
this:--

    It puzzles me greatly to know what makes the successful
    philosopher. Is it industry and perseverance with a moderate
    proportion of good sense and intelligence? Is not a modest
    assurance or earnestness a requisite? Do not many fail because
    they look rather to the renown to be acquired than to the pure
    acquisition of knowledge, and the delight which the contented
    mind has in acquiring it for its own sake? I am sure I have
    seen many who would have been good and successful pursuers of
    science, and have gained themselves a high name, but that it
    was the name and the reward they were always looking forward
    to--the reward of the world’s praise. In such there is always a
    shade of envy or regret over their minds, and I cannot imagine
    a man making discoveries in science under these feelings. As to
    Genius and its power, there may be cases; I suppose there are.
    I have looked long and often for a genius for our Laboratory,
    but have never found one. But I have seen many who would, I
    think, if they had submitted themselves to a sound self-applied
    discipline of mind, have become successful experimental
    Philosophers.

To Dr. Becker he wrote:

    I was never able to make a fact my own without seeing it; and
    the descriptions of the best works altogether failed to convey
    to my mind such a knowledge of things as to allow myself to
    form a judgment upon them. It was so with _new_ things. If
    Grove, or Wheatstone, or Gassiot, or any other told me a new
    fact, and wanted my opinion either of its value, or the cause,
    or the evidence it could give on any subject, I never could say
    anything until I had seen the fact. For the same reason I never
    could work, as some Professors do most extensively, by students
    or pupils. All the work had to be my own.

[Sidenote: INCOME AND EXPENDITURE.]

Of Faraday’s social life and surroundings during his meridional and
later period much might be written. After his great researches of 1831
to 1836 scientific honours flowed in freely upon him, especially from
foreign academies and universities; and the fame he won at home would
have brought him, had he been so minded, an ample professional fortune
and all the artificial amenities of Society which follow the successful
money-maker. From all such mundane “success” he cut himself off when
in 1831 he decided to abandon professional fee-earning, and to devote
himself to the advancement of science. Probably the tenets of the
religious body to which he belonged were a leading factor in compelling
this decision. Not having laid upon him the necessity of providing
for a family, and accustomed to live in an unostentatious style, he
could contemplate the future without anxiety. With his pension, his
Woolwich lectures, and his Trinity House appointment, Faraday was in no
sense poor, though his Royal Institution professorship never brought
him so much as £300 a year until after he was over sixty years of age;
but on the other hand, his private charities were very numerous. How
much of his income was spent in that way can never be known; for the
very privacy of his deeds of kindness prevented any record from being
kept. Certain it is that his gifts to the aged poor and sick must have
amounted to several hundreds of pounds a year; for while his income
for many years must have averaged at least £1,000 or £1,100, and his
domestic expenditure could not have much exceeded half that sum, he
does not seem to have attempted to save anything. Nor did he grudge
time or strength to do kindly charitable acts in visiting the sick.

From about the year 1834 he resolutely declined invitations to dinners
and such social gaieties; not, as some averred, from any religious
asceticism, but that he might the more unrestrainedly devote himself to
his researches. “If,” says Mrs. Crosse, “Babbage, Wheatstone, Grove,
Owen, Tyndall, and a host of other distinguished scientists, were to be
met very generally in the society of the day, there was one man who was
very conspicuous by his absence--this was Faraday! His biographers say
that in earlier years he occasionally accepted Lady Davy’s invitations
to dinner; but I never heard of his going anywhere, except in obedience
to the commands of royalty.” He did indeed occasionally dine quietly
with Sir Robert Peel or Earl Russell; and of the few public dinners he
attended, he enjoyed most the annual banquet of the Royal Academy of
Arts.

Faraday does not, however, appear to have had any very direct relations
with the world of art. Once he was consulted by Lord John Russell
as to the removal of Raphael’s cartoons from Hampton Court to the
National Gallery. His advice was adverse, on account of the penetrating
power of dust. Though a sufficiently good draughtsman to prepare his
own drawings, he had little or no knowledge of the technicalities of
painting. Yet his sensitive and enthusiastic temperament had much in
common with that of the artist, and he enjoyed music, especially good
music, greatly. In early life he played the flute and knew many songs
by heart. He took bass parts in concerted singing, and is said to have
sung correctly in time and tune. In his circle of acquaintanceship
were numbered several painters of eminence--Turner, Landseer, and
Stanfield. His brother-in-law, Mr. George Barnard, the late well-known
water-colour artist, has written the following note:--

    My first and many following sketching trips were made with
    Faraday and his wife. Storms excited his admiration at all
    times, and he was never tired of looking into the heavens. He
    said to me once, “I wonder you artists don’t study the light
    and colour in the sky more, and try more for effect.” I think
    this quality in Turner’s drawings made him admire them so much.
    He made Turner’s acquaintance at Hullmandel’s, and afterwards
    often had applications from him for chemical information about
    pigments. Faraday always impressed upon Turner and other
    artists the great necessity there was to experiment for
    themselves, putting washes and tints of all their pigments in
    the bright sunlight, covering up one half, and noticing the
    effect of light and gases on the other....

    Faraday did not fish at all during these country trips, but
    just rambled about geologising or botanising.

[Sidenote: SCIENCE, LITERATURE, AND ART.]

Earlier in his career, Faraday and his brother-in-law used to enjoy
conversaziones of artists, actors, and musicians at Hullmandel’s.
Sometimes they went up the river in Hullmandel’s eight-oar boat,
camping gipsy-wise on the banks for dinner, and enjoying the singing
of Signor Garcia and his wife and of his daughter, afterwards Madame
Malibran. From these things, too, he withdrew very largely when he
ceased to dine out, though he still liked to hear the opera and
to visit the theatre. Curiously enough, he seems to have had very
little in common with literary men. In the last half of the previous
century there had been many intimate relations between the leaders
of literature and those of science. The circle which included Watt,
Boulton, and Wedgwood included also Priestley and Erasmus Darwin. In
our own time the names of Darwin, Huxley, Hooker, and Tyndall are to
be found in conjunction with those of Tennyson, Browning, and Jowett.
But the biographies of literary men and artists of the period from 1830
to 1850 bear few references to Faraday. He moved in his own world, and
that a world very much apart from literature or art. In his method of
working he was indeed an artist, often feeling his way rather than
calculating it, and arriving at his conclusions by what seemed insight
rather than by any direct process of reasoning. The discovery of
truth comes about in many ways; and if Faraday’s method in science
was artistic rather than scientific, it was amply justified by the
brilliant harvest of discoveries which it enabled him to reap.

As is well known, Faraday never took out any patents for his
discoveries; indeed, whenever in his investigations he seemed to come
near to the point where they began to possess a marketable value
from their application to the industries, he left them, to pursue
his pioneering inquiries in other branches. He sought, indeed, for
principles rather than for processes, for facts new to science rather
than for merchantable inventions. When he had made the discovery
of magneto-electric induction--the basis of all modern electric
engineering--he carried the research to the point of constructing
several experimental machines, and then abruptly turned away with these
memorable words:--

    I have rather, however, been desirous of discovering new facts
    and new relations dependent on magneto-electric induction than
    of exalting the force of those already obtained; being assured
    that the latter would find their full development hereafter.

[Sidenote: PRACTICAL UTILITIES.]

Several times was Faraday known, when asked about the possible utility
of some new scientific discovery, to quote Franklin’s rejoinder: “What
is the use of a baby?”

It is narrated of him that on one occasion, at a Trinity House dinner,
he and the Duke of Wellington had a little friendly chat, in the
course of which the Duke advised Faraday to give his speculations “a
practical turn as far as possible”--“a suggestion,” said Faraday, who
always spoke of the veteran with pleasure, “full of weight, coming
from such a man.” Faraday was, however, the last to despise the
importance of industrial applications of science. In his unpublished
manuscripts at the Royal Institution there are some curious references
to trials which he made of a meat-canning process, invented about
1848 by a Mr. Goldner, of Finsbury. He also had fancies for other
domestic applications, including wine-making. He used himself to
bind his own note-books. To a Mr. Woolnough, who had written a book
on the marbling of paper, he wrote a letter saying how much interest
he felt in the subject, “because of its associations with my early
occupation of bookbinding; and also because of the very beautiful
principles of natural philosophy which it involves.” He even, on one
occasion, produced a home-made pair of boots. His devotion to the
practical applications of science is attested by his untiring work for
improving the lighthouses of our coast. It is believed that his death
was accelerated by a severe cold caught when on a visit of lighthouse
inspection during stormy weather.

Faraday was never ashamed of the circumstance of his having risen
from a humble origin. In his letters he not unfrequently alludes to
things that remind him of his bookbinding experiences, or of boyish
episodes in his father’s smithy. Yet he had none of the vulgar
pride of ascent which too often dogs the path of the self-made man.
Severe self-discipline and genuine humility prevented either undue
proclamation or awkward reticence respecting his early life. His elder
brother Robert was a gasfitter. Faraday was not ashamed to help him to
secure work in his trade, nor to give him the benefit of his scientific
aid in perfecting appliances for ventilating by gas-burners. The
following characteristic story was told by Frank Barnard:--

    Robert was throughout life a warm friend and admirer of his
    younger brother, and not a whit envious at seeing himself
    passed in the social scale by him. One day he was sitting in
    the Royal Institution just previous to a lecture by the young
    and rising philosopher, when he heard a couple of gentlemen
    behind him descanting on the natural gifts and rapid rise of
    the lecturer. The brother--perhaps not fully apprehending the
    purport of their talk--listened with growing indignation while
    one of them dilated on the lowness of Faraday’s origin. “Why,”
    said the speaker, “I believe he was a mere shoeblack at one
    time.” Robert could endure this no longer; but turning sharply
    round he demanded: “Pray, sir, did he ever black your shoes?”
    “Oh! dear no, certainly not,” replied the gentleman, much
    abashed at the sudden inquisition into the facts of the case.

[Sidenote: SPIRIT MEDIUMS EXPOSED.]

In 1853 Faraday came before the public in a novel manner--as the
exposer of the then rampant charlatanry of table-turning and
spirit-rapping. The _Athenæum_ for July 2nd contains a long letter
from him on table-turning. He experimentally investigated the alleged
phenomena as produced by three skilful mediums in _séances_ at the
house of a friend. His mechanical skill was more than a match, however,
for that of the supposed spirits. When the observers assembled around
the table placed their hands in the orthodox way upon the table-top,
the table turned, apparently without any effort on the part of any
one of the party. This was eminently satisfactory for the spirits.
But when Faraday interposed between each hand and the table-top a
simple roller-mechanism which, if any individual in the circle applied
muscular forces tending to turn it, instantly indicated the fact, the
table remained immovable. Faraday wrote merely describing the facts,
and saying that the test apparatus was now on public view at 122,
Regent Street. He ends thus:--

    I must bring this long description to a close. I am a little
    ashamed of it, for I think, in the present age, and in this
    part of the world, it ought not to have been required.
    Nevertheless, I hope it may be useful. There are many whom I
    do not expect to convince; but I may be allowed to say that I
    cannot undertake to answer such objections as may be made. I
    state my own convictions as an experimental philosopher, and
    find it no more necessary to enter into controversy on this
    point than on any other in science, as the nature of matter, or
    inertia, or the magnetisation of light, on which I may differ
    from others. The world will decide sooner or later in all such
    cases, and I have no doubt very soon and correctly in the
    present instance.

This exposure excited great interest at the time, and there was an
active correspondence in _The Times_. The spiritualists, instead of
appreciating the services to truth rendered by the man of science,
railed bitterly at him. Even the refined and noble spirit of Mrs.
Browning was so dominated by the superstition of the moment that, as
shown by her recently published letters, she denounced Faraday in
singularly acrimonious terms, and taunted him for shallow materialism!
What Faraday thought of the hubbub evoked by his action is best learned
from a letter which he addressed three weeks later to his friend
Schönbein:--

    I have not been at work except in turning the tables upon
    the table-turners, nor should I have done that, but that so
    many inquiries poured in upon me, that I thought it better to
    stop the inpouring flood by letting all know at once what my
    views and thoughts were. What a weak, credulous, incredulous,
    unbelieving, superstitious, bold, frightened, what a ridiculous
    world ours is, as far as concerns the mind of man. How full
    of inconsistencies, contradictions, and absurdities it is.
    I declare that, taking the average of many minds that have
    recently come before me (and apart from that spirit which God
    has placed in each), and accepting for a moment that average
    as a standard, I should far prefer the obedience, affections,
    and instinct of a dog before it. Do not whisper this, however,
    to others. There is One above who worketh in all things, and
    who governs even in the midst of that misrule to which the
    tendencies and powers of men are so easily perverted.

He declined an invitation in 1855 to see manifestations by the medium
Home, saying that he had “lost too much time about such matters
already.” Nine years later the Brothers Davenport invited him to
witness their cabinet “manifestations.” Again he declined, and added:
“I will leave the spirits to find out for themselves how they can move
my attention. I am tired of them.”

In this year he wrote to _The Times_ respecting the disgraceful and
insanitary condition of the river Thames. In _Punch_ of the following
week appeared a cartoon representing Faraday presenting his card to old
Father Thames, who rises holding his nose to avoid the stench.

[Sidenote: FAILURE OF MEMORY.]

With increasing age the infirmity of loss of memory made itself
increasingly felt. He alludes frequently to this in his letters. To
one friend who upbraided him gently for not having replied to a letter
he says: “Do you remember that I forget?” To another he says he is
forgetting how to spell such words as “withhold” and “successful.” To
Matteucci, in 1849, he bemoans how, after working for six weeks at
certain experiments, he found, on looking back to his notes, he had
ascertained all the same results eight or nine months before, and had
entirely forgotten them! In the same year he wrote to Dr. Percy:--

    I cannot be on the Committee; I avoid everything of that kind,
    that I may keep my stupid head a little clear. As to being on a
    Committee and not working, that is worse still.

In 1859, in a letter to his niece, Mrs. Deacon, filled mainly with
religious thoughts, he says: “My worldly faculties are slipping away
day by day. Happy is it for all of us that the true good lies not in
them.”

From the journals of Walter White comes the following anecdote under
date December 22nd, 1858:--

    Mr. Faraday called to enquire on the part of Sir Walter
    Trevelyan whether a MS. of meteorological observations made
    in Greenland would be acceptable. The question answered, I
    expressed my pleasure at seeing him looking so well, and asked
    him if he were writing a paper for the Royal. He shook his
    head. “No: I am too old.” “Too old? Why, age brings wisdom.”
    “Yes, but one may overshoot the wisdom.” “You cannot mean that
    you have outlived your wisdom?” “Something like it, for my
    memory is gone. If I make an experiment, I forget before twelve
    hours are over whether the result was positive or negative; and
    how can I write a paper while that is the case? No, I must
    content myself with giving my lectures to children.”

From another source we learn of a hitherto unrecorded incident which
happened to Mr. Joseph Newton, for some time an assistant in the Royal
Mint. While arranging some precious material on the Royal Institution
theatre lecture-table, previous to a lecture on the Mint and minting
operations by Professor Brande, Mr. Newton noticed an elderly, spare,
and very plainly-dressed individual watching his movements. Imagining
that this person was a superior messenger of the Institution, Mr.
Newton volunteered some information as to the coinage of gold. “I
suppose,” said the Mint employee, “you have been some years at the
Royal Institution?” “Well, yes, I have, a good many,” responded the
dilapidated one. “I hope they treat you pretty liberally--I mean, that
they give you a respectable ‘screw,’ for that is the main point.” “Ah!
I agree with you there. I think that the labourer is worthy of his
hire, and I shouldn’t mind being paid a little better.” Mr. Newton’s
surprise, on returning to the Royal Institution in the evening, to find
that the man whom he had so recently patronised was none other than
the illustrious but modest Michael Faraday can better be imagined than
described.

A pretty instance, given on the authority of Lady Pollock, may be
recorded of the feeling aroused by Faraday’s presence when he returned
to his accustomed seat in the lecture-room of the Royal Institution,
after a protracted absence occasioned by illness:--

    As soon as his presence was recognised, the whole audience
    rose simultaneously and burst into a spontaneous utterance of
    welcome, loud and long. Faraday stood in acknowledgment of this
    enthusiastic greeting, with his fine head slightly bent; and
    then a certain resemblance to the pictures and busts of Lord
    Nelson, which was always observable in his countenance, was
    very apparent. His hair had grown white and long, his face had
    lengthened, and the agility of his movement was gone. The eyes
    no longer flashed with the fire of the soul, but they still
    radiated kindly thought; and ineffaceable lines of intellectual
    force and energy were stamped upon his face.

[Sidenote: HONOURS OFFERED AND DECLINED.]

In 1857 he was offered the Presidency of the Royal Society. A painting
preserved in the rooms of the Royal Society records the scene when Lord
Wrottesley, Grove, and Gassiot waited upon him as a deputation from
the Council, to press on him his acceptance of the highest place which
science has to offer. He hesitated and finally declined, even as he
had declined the suggestion of knighthood years before. “Tyndall,” he
said in private to his successor, “I must remain plain Michael Faraday
to the last; and let me now tell you, that if I accepted the honour
which the Royal Society desires to confer upon me, I could not answer
for the integrity of my intellect for a single year.” He also declined
the Presidency of the Royal Institution, which he had served for fifty
years. His one desire was for rest. “The reverent affection of his
friends was,” said Tyndall, “to him infinitely more precious than all
the honours of official life.”

Allusion has been made to Faraday’s tender and chivalrous regard
for his wife. Extracts from two letters, written in 1849 and 1863
respectively, must here suffice to complete the story:--

                                    Birmingham, Dr. Percy’s:
                              Thursday evening, September 13, 1849.

    MY DEAREST WIFE,--I have just left Dr. Percy’s hospitable
    table to write to you, my beloved, telling you how I have been
    getting on. I am very well, excepting a little faceache; and
    very kindly treated here. They all long most earnestly for your
    presence, for both Mrs. and Dr. Percy are anxious you should
    come; and this I know, that the things we have seen would
    delight you, but then I doubt your powers of running about as
    we do; and though I know that if time were given you could
    enjoy them, yet to press the matter into a day or two would
    be a failure. Besides this, after all, there is no pleasure
    like the tranquil pleasures of home, and here--even here--the
    moment I leave the table, I wish I were with you IN QUIET. Oh!
    what happiness is ours! My runs into the world in this way only
    serve to make me esteem that happiness the more. I mean to be
    at home on Saturday night, but it may be late first, so do not
    be surprised at that; for if I can, I should like to go on an
    excursion to the Dudley caverns, and that would take the day....

    Write to me, dearest. I shall get your letter on Saturday
    morning, or perhaps before.

    Love to father, Margery, and Jenny, and a thousand loves to
    yourself, dearest,

                              From your affectionate husband,
                                                        M. FARADAY.

       *       *       *       *       *

                                        5, Claremont Gardens, Glasgow:
                                            Monday, August 14, 1863.

    DEAREST,--Here is the fortnight complete since I left you and
    the thoughts of my return to _our home_ crowd in strongly upon
    my mind. Not that we are in any way uncared for, or left by
    our dear friends, save as I may desire for our own retirement.
    Everybody has overflowed with kindness, but you know their
    manner, and their desire, by your own experience with me. I
    long to see you, dearest, and to talk over things together, and
    call to mind all the kindness I have received. My head is full,
    and my heart also, but my recollection rapidly fails, even as
    regards the friends that are in the room with me. You will have
    to resume your old function of being a pillow to my mind, and a
    rest, a happy-making wife.

    My love to my dear Mary. I expect to find you together, but do
    not assume to know how things may be.

    Jeannie’s love with mine, and also Charlotte’s, and a great
    many others which I cannot call to mind.

    Dearest, I long to see and be with you, whether together or
    separate.

                              Your husband, very affectionate,
                                                          M. FARADAY


[Sidenote: THE WIFE AND THE QUEEN.]

In 1858 the Queen, at the suggestion of Prince Albert, who much
esteemed and valued Faraday’s genius, placed at his disposal for life
a comfortable house on the green near Hampton Court. Faraday’s only
hesitation in accepting the offer was a doubt whether he could afford
the needful repairs. On a hint of this reaching the Queen, she at once
directed that it should be put into thorough repair inside and out. He
still kept his rooms at the Royal Institution, and continued to live
there occasionally.

With the increasing infirmities of age, his anxieties for his wife
seemed to be the only trouble that marred the serenity of his thought.
Lady Pollock’s narrative gives the following particulars:--

    Sometimes he was depressed by the idea of his wife left without
    kin--of the partner of his hopes and cares deprived of him. She
    had been the first love of his ardent soul; she was the last;
    she had been the brightest dream of his youth, and she was the
    dearest comfort of his age; he never ceased for an instant to
    feel himself happy with her; and he never for one hour ceased
    to care for her happiness. It was no wonder, then, that he felt
    anxiety about her. But he would rally from such a trouble with
    his great religious trust, and looking at her with moist eyes,
    he would say, “I must not be afraid; you will be cared for, my
    wife; you will be cared for.”

    There are some who remember how tenderly he used to lead her to
    her seat at the Royal Institution when she was suffering from
    lameness; how carefully he used to support her; how watchfully
    he used to attend all her steps. It did the heart good to see
    his devotion, and to think what the man was and what he had
    been.

[Illustration: FIG. 22.--FARADAY’S HOME AT HAMPTON COURT.]

[Sidenote: CLOSE OF SCIENTIFIC CAREER.]

Gradually his powers waned. He gave his last juvenile lectures at
Christmas, 1860; and in October, 1861, being now seventy years of age,
he resigned his Professorship, while retaining the superintendence
of the laboratory. “Nothing,” he wrote to the managers, “would make
me happier in the things of this life than to make some scientific
discovery or development, and by that to justify the Board in their
desire to retain me in my position here.” His last research in the
laboratory was made on March 12, 1862. On June 20th he gave his last
Friday night discourse--on Siemens’s gas furnaces. He had, as his
notes show, already made up his mind to announce his retirement, and
the lecture was a sad and touching occasion, for the failure of his
powers was painfully evident. He continued for two years longer, and
with surprising activity, to work for Trinity House on the subject of
lighthouse illumination by the electric light. In 1865 he resigned
these duties to Dr. Tyndall. In 1864 he resigned his eldership in
the Sandemanian church. In March, 1865, he resigned the position of
superintendent of the house and laboratories of the Royal Institution.
He continued to attend the Friday evening meetings; but his tottering
condition of frame and mind was apparent to all. All through the winter
of 1865 and 1866 he became very feeble. Yet he took an interest in Mr.
Wilde’s description of his new magneto-electric machine. Almost the
last pleasure he showed on any scientific matter was when viewing the
long spark of a Holtz’s influence machine. He still enjoyed looking
at sunsets and storms. All through the summer and autumn of 1866 and
the spring of 1867 his physical powers waned. He was faithfully and
lovingly tended by his wife and his devoted niece, Jane Barnard.
He was scarcely able to move, but his mind “overflowed” with the
consciousness of the affectionate regard of those around him. He
gradually sank into torpor, saying nothing and taking little notice of
anything. Sitting in his chair in his study, he died peacefully and
painlessly on the 26th of August, 1867. On the 30th of August he was
quietly buried in Highgate Cemetery, his remains being committed to the
earth, in accordance with the custom of the religious body to which he
belonged, in perfect silence. None but personal friends were present,
the funeral being by his own verbal and written wishes strictly simple
and private. A simple unadorned tombstone marks the last resting-place
of Michael Faraday.




CHAPTER VII.

VIEWS ON THE PURSUIT OF SCIENCE AND ON EDUCATION.


Between Faraday and the scientific men of his time there subsisted
many various relations. The influence which he exerted as a lecturer
and as an experimental investigator was unique; but, apart from
such influences, those relations were mainly confined to individual
friendships. With the organisation of science he had relatively very
little to do. We have seen how highly he prized the honour of admission
to the Fellowship of the Royal Society; and it remains to be told of
the gratification with which he accepted the scientific honours which
he received from almost every academy and university in Europe. Yet
he took little part in the work of scientific societies as such. Four
years after his election as F.R.S. he served on the Council, and he
remained on till 1831. He served again in 1833 and 1835. He was not,
however, satisfied with the management of the Royal Society, nor with
the way in which its Fellowship was at that time bestowed on men who
had no real claims on science, but were nominated through influence.
Echoes of this discontent are to be found in various pamphlets of the
day by Moll, Babbage, South, and others. Faraday, who edited Moll’s
pamphlet on the “Decline of Science,” is believed to have had an even
larger share in its production. In 1830 the really scientific men
amongst the Fellows desired to place Sir John Herschel as President;
the less scientific preferred the Duke of Sussex. Faraday took the
unusual step of speaking on the question, advocating the principle
that eminence in science should be the sole qualification for the
Presidency. At the same meeting Herschel moved, and Faraday seconded,
a plan for reforming the Council by nominating a list of fifty Fellows
from whose number the Council should be chosen. They carried their
plan, and Faraday’s name was amongst those so selected to serve. But
the presidential election went in favour of the Duke of Sussex by 119
to 110 votes. After 1835 Faraday never served again on the Council. In
1843 he wrote to Matteucci:--

    I think you are aware that I have not attended at the Royal
    Society, either meetings or council, for some years. Ill health
    is one reason, and another that I do not like the present
    constitution of it, and want to restrict it to scientific men.
    As these my opinions are not acceptable, I have withdrawn from
    any management in it (still sending scientific communications
    if I discover anything I think worthy). This, of course,
    deprives me of power there.

[Sidenote: REFORM IN THE ROYAL SOCIETY.]

Two months earlier he wrote to Grove, who at that time was carrying out
the long-needed reforms, sympathising, but declining to co-operate:--

                                        Royal Institution,
                                            December 21, 1842.

    MY DEAR GROVE,--... As to the Royal Society, you know my
    feeling towards it is for what it has been, and I hope may be.
    Its present state is not wholesome. You are aware that I am
    not on the council, and have not been for years, and have been
    to no meeting there for years; but I do hope for better times.
    I do not wonder at your feeling--all I meant to express was a
    wish that its circumstances and character should improve, and
    that it should again become a desirable reunion of _all_ really
    scientific men. It has done much, is now doing much, in some
    parts of science, as its magnetic observations show, and I hope
    will some day become altogether healthy.

                              Ever, my dear Grove, yours sincerely,
                                                          M. FARADAY.


Though he continued down to 1860 to send researches for publication
to the Royal Society, he seldom attended its meetings.[56] He was not
even present in November, 1845, on the occasion of the reading of his
paper on the action of the magnet on light. In 1857 he declined the
Presidency, though urged by the unanimous wish of the Council, as
narrated on p. 225.

Though in the meridian of his active life, he took no part in the
founding of the British Association in 1831, but was at the Oxford
meeting in 1832, being one of the four scientific men (p. 65) selected
to receive the honorary degree of D.C.L. on that occasion. He also
communicated a paper on Electro-chemical Decomposition to the B.A.
meeting at Cambridge in 1833. He acted as president of the Chemical
Section of the Association in 1837 at Liverpool, and in 1846 at
Southampton; and he was chosen as vice-president of the Association
itself in the years 1844, at York (p. 224); 1849, at Birmingham (p.
256); and 1853, at Hull. He delivered evening discourses in 1847,
at Oxford, on Magnetic and Diamagnetic Phenomena; and in 1849, at
Birmingham, on Mr. Gassiot’s Battery. He also contributed to the
proceedings at the meetings at Ipswich in 1851 and at Liverpool in 1854.

His comparative aloofness from scientific organisations arose probably
from the exceedingly individual nature of his own researches--to which
allusion was made on p. 242--rather than from any lack of sympathy.
He had no jealousy of co-operation in science. To Tyndall, then at
Marburg, he wrote in 1850 rejoicing at the circumstance that the work
on the magnetic properties of crystals was being taken up by others.
“It is wonderful,” he says, “how much good results from different
persons working at the same matter. Each one gives views and ideas new
to the rest. When science is a republic, then it gains; and though I am
no republican in other matters, I am in that.” Other causes there were,
doubtless, tending to his isolation, amongst them an old jealousy, now
long dead, against the Royal Institution on the part of some of the
Fellows of the Royal Society. Above all, probably, was his detestation
of controversy.

[Sidenote: PRIORITY IN SCIENTIFIC DISCOVERY.]

[Sidenote: PRIORITY IN PUBLICATION.]

Priority in scientific discovery was a matter which deeply concerned
one whose life was devoted to scientific pioneering. To any question
as to scientific priority between himself and other workers he was
keenly sensitive. This was, indeed, natural in one who had voluntarily
relinquished fortune, and retired from lucrative professional work,
in the sole and single aim of advancing natural knowledge. His
single-minded and sensitive nature made him particularly scrupulous
in all such matters, and his early experiences must have added to the
almost excessive keenness of his perceptions. Having had in 1823,
when still merely assistant to Davy, to bear the double burden of a
serious misunderstanding with Dr. Wollaston as to the originality of
his discovery of the electro-magnetic rotations, and of a serious
estrangement from his master arising out of the liquid chlorine
discovery--an estrangement which threatened to cause his election to
the Royal Society to be indefinitely postponed--he was in later life
especially precise in dating and publishing his own researches. In
1831 there arose, concerning his great discovery of magneto-electric
induction, a curious misunderstanding. His discovery was, as we have
seen, made in September and October. He collected his results and
arranged them in the splendid memoir--the first in the series of
“Experimental Researches in Electricity”--which was read at the Royal
Society on November 24th. The _résumé_ of his work, which he wrote
five days later to Phillips, is given on pages 114–117. A fortnight
later he wrote a shorter and hasty letter in the same way to his
friend, M. Hachette of Paris--a letter which Faraday subsequently
well termed “unfortunate,” in view of the consequences that followed.
M. Hachette, a week later, communicated Faraday’s letter to the
Académie des Sciences on December 26th. It was published in _Le
Temps_ of December 28th. At that date the complete memoir read to
the Royal Society was not yet printed or circulated. The consequence
was that two Italian physicists, MM. Nobili and Antinori, seeing the
brief letter, and “considering that the subject was given to the
philosophical world for general pursuit,” immediately began researches
on magneto-electric induction in ignorance of Faraday’s full work.
Their results they embodied in a paper, in which they claimed to
have “verified, extended, and, perhaps, rectified the results of the
English philosopher,” accusing him of errors both in experiment and
theory, and even of a breach of good faith as to what he had said
about Arago’s rotations. This paper they dated January 31st, 1832;
but it was published in the belated number of the _Antologia_ for
November, 1831, where its appearance at an apparently earlier date
than Faraday’s original paper in the _Philosophical Transactions_ made
many Continental readers suppose that the researches of Nobili and
Antinori preceded those of Faraday. In June, 1832, Faraday published
in the _Philosophical Magazine_ a translation of Nobili’s memoir, with
his own annotations; and later in the year he wrote to Gay Lussac a
long letter on the errors of Nobili and Antinori. He showed how, in
spite of his efforts to clear up the misunderstanding, in spite of
his having sent several months previously to MM. Nobili and Antinori
copies of his original papers, no correction or retractation had
been made by them; and he concluded by a dignified protest that none
might say he had been too hasty to write that which might have been
avoided. It may be taken that the rule now recognised as to priority
of scientific publication--namely, that it dates from the day when the
discoverer communicates it formally to any of the recognised learned
societies--was virtually established by Faraday’s example. It will
be remembered that writing to De la Rive in 1845, to tell him of his
diamagnetic discoveries, he begged him to keep the matter secret,
adding: “I ought (in order to preserve the respect due to the Royal
Society) not to write a description to any one until the paper has
been received or even read there.” To younger men he inculcated the
necessity of proper and prompt publication of their researches if they
would reap the benefit of their work. To Sir William Crookes, then a
rising young chemist, he said: “Work, Finish, Publish.” Writing in 1853
to Professor Matteucci, who had been annoyed with him for allowing
Du Bois Reymond, with whom Matteucci had had some controversy about
priority, to dedicate his book to him, Faraday says: “Who has not to
put up in his day with insinuations and misrepresentations in the
accounts of his proceedings given by others, bearing for the time the
present injustice, which is often unintentional, and often originates
in hasty temper, and committing his fame and character to the judgment
of the men of his own and future time?”... “I see that that moves
you which would move me most--namely, the imputation of a want of
good faith--and I cordially sympathise with any one who is so charged
unjustly. Such cases have seemed to me almost the only ones for which
it is worth while entering into controversy.”... “These polemics of the
scientific world are very unfortunate things; they form the great stain
to which the beautiful edifice of scientific truth is subject. _Are
they inevitable?_”

Controversy whether in religion or science was to him alike detestable.
He took no part in politics. A letter to Tyndall (see “Faraday as a
Discoverer,” p. 39), written after the latter had told him of a rather
heated discussion at the British Association meeting in 1855, speaks of
his own efforts at forbearance. He says:--

    These great meetings, of which I think very well altogether,
    advance science chiefly by bringing scientific men together
    and making them to know and be friends with each other; and I
    am sorry when that is not the effect in every part of their
    course.... The real truth never fails ultimately to appear....
    It is better to be blind to the results of partisanship, and
    quick to see good will. One has more happiness in oneself in
    endeavouring to follow the things that make for peace. You can
    hardly imagine how often I have been heated in private when
    opposed, as I have thought unjustly and superciliously, and yet
    I have striven, and succeeded I hope, in keeping down replies
    of the like kind. And I know I have never lost by it.

[Sidenote: HATRED OF CONTROVERSY.]

During the years when he was examining the apparatus of rival inventors
for lighthouse illumination, he could calmly hear them described as
Mr. So-and-So’s electric lights, all the while knowing that it was
his own discovery of magneto-electric induction which had made the
mechanical production of electric light possible. Yet he fired up if
anyone dared to revive the priority dispute between Davy and Stephenson
as to the invention of the safety lamp. “Disgraceful subject,” was
his own comment. In his dispute with Snow Harris as to the design of
lightning rods, in which, as it is now known, Snow Harris was right;
in his dispute with Airy over the curved lines of force; in his minor
difficulties over Hare’s pile and Becquerel’s magnetic observations,
none could either assert his own position with more simple dignity, nor
admit with greater frankness the rights of his rival.

To Hare he wrote:--

    You must excuse me, however, for several reasons from answering
    it [Hare’s letter] at any length; the first is my distaste for
    controversy, which is so great that I would on no account our
    correspondence should acquire that character. I have often
    seen it do great harm, and yet remember few cases in natural
    knowledge where it has helped much either to pull down error or
    advance truth. Criticism, on the other hand, is of much value.

When we reflect how large a part of his experimental researches was
devoted to establishing the relations between the various forces of
nature, we cannot but think that Faraday must have regarded with
somewhat mixed feelings the publication in 1846 of Sir William Grove’s
volume on the Correlation of Forces. He had, in June, 1834, given a
course of lectures on the mutual relation of chemical and electrical
phenomena, and had dealt therein with the conversion of chemical and
electrical power into heat, and had speculated on the inclusion of
gravitation in these mutual relations. In 1853 Faraday marked the old
lecture notes of these lectures with his initials, and endorsed them
with the words “Correlation of Physical Forces.” Probably none rejoiced
more than he that Grove had undertaken the work of popularising the
notion which for a score of years had been familiar to himself. Yet
he was keen to resent an unjust reflection, as is shown by his letter
to Richard Phillips, republished in Vol. II. of the “Experimental
Researches,” p. 229, respecting Dr. John Davy’s Life of Sir Humphry.

Faraday has himself left on record (p. 10) that when he wrote to Davy
asking to be taken into his employment, his motive was his desire “to
escape from trade, which I thought vicious and selfish, and to enter
into the service of Science, which, I imagined, made its pursuers
amiable and liberal.” Davy had smiled at this boyish notion, and had
told him that the experience of a few years would correct his ideas.
Years afterwards he spoke of this matter to Mrs. Andrew Crosse in an
interview which she has recorded:--

    After viewing the ample appliances for experimental research,
    and feeling much impressed by the scientific atmosphere of the
    place, I turned and said, “Mr. Faraday, you must be very happy
    in your position and with your pursuits, which elevate you
    entirely out of the meaner aspects and lower aims of common
    life.”

    He shook his head, and with that wonderful mobility of
    countenance which was characteristic, his expression of
    joyousness changed to one of profound sadness, and he replied:
    “When I quitted business and took to science as a career, I
    thought I had left behind me all the petty meannesses and small
    jealousies which hinder man in his moral progress; but I found
    myself raised into another sphere, only to find poor human
    nature just the same everywhere--subject to the same weaknesses
    and the same self-seeking, however exalted the intellect.”

    These were his words as well as I can recollect; and, looking
    at that good and great man, I thought I had never seen a
    countenance which so impressed me with the characteristic of
    perfect unworldliness.

[Sidenote: HONOURS AND TITLES.]

Probably few men have ever been recipients of so many scientific
honours as Faraday. Beginning in the year 1823 with his election as a
corresponding member of the Académie des Sciences of Paris, and as an
honorary member of the Cambridge Philosophical Society, the list of
his diplomas and distinctions--some ninety-seven in number--ended in
1864 with his election as Associate of the Royal Academy of Sciences of
Naples. It included honours from almost every academy and university
of Europe. These honours Faraday valued very highly; and whilst he
consigned his various gold medals to a mere wooden box, his diplomas
were kept with the utmost care in a special diploma book, in which they
were mounted and indexed. To Mr. Spring Rice, who in 1838 asked him for
a list of his titles, he replied, enclosing the list, and adding this
remark: “One title, namely that of F.R.S., was sought and paid for;
all the rest are spontaneous offerings of kindness and goodwill from
the bodies named.” Years afterwards he was asked by Lord Wrottesley
to advise the Government as to how the position of science or of the
cultivators of science in England might be improved. The letter is so
characteristic that it cannot be spared:--

                              Royal Institution: March 10, 1854.

    MY LORD,--I feel unfit to give a deliberate opinion on the
    course it might be advisable for the Government to pursue
    if it were anxious to improve the position of science and
    its cultivators in our country. My course of life, and the
    circumstances which make it a happy one for me, are not those
    of persons who conform to the usages and habits of society.
    Through the kindness of all, from my Sovereign downwards,
    I have that which supplies all my need; and in respect of
    honours, I have, as a scientific man, received from foreign
    countries and sovereigns those which, belonging to very limited
    and select classes, surpass in my opinion anything that it is
    in the power of my own to bestow.

    I cannot say that I have not valued such distinctions; on the
    contrary, I esteem them very highly, but I do not think I have
    ever worked for or sought after them. Even were such to be now
    created here, the time is past when these would possess any
    attraction for me....

    Without thinking of the effect it might have upon distinguished
    men of science, or upon the minds of those who, stimulated
    to exertion, might become distinguished, I do think that a
    government should, _for its own sake_, honour the men who do
    honour and service to the country. I refer now to honours only,
    not to beneficial rewards. Of such honours, I think, there
    are none. Knighthoods and baronetcies are sometimes conferred
    with such intentions, but I think them utterly unfit for that
    purpose. Instead of conferring distinction, they confound the
    man who is one of twenty, or perhaps fifty, with hundreds of
    others. They depress rather than exalt him, for they tend to
    lower the especial distinction of mind to the commonplace
    of society. An intelligent country ought to recognise the
    scientific men amongst its people as a class. If honours are
    conferred upon eminence in any class, as that of the law or
    the army, they should be in this also. The aristocracy of
    the class should have other distinctions than those of lowly
    and high-born, rich and poor, yet they should be such as to
    be worthy of those whom the sovereign and the country should
    delight to honour; and, being rendered very desirable, and even
    enviable, in the eyes of the aristocracy by birth, should be
    unattainable except to that of science. Thus much, I think,
    the Government and the country ought to do, for their own sake
    and the good of science, more than for the sake of the men who
    might be thought worthy of such distinction. The latter have
    attained to their fit place, whether the community at large
    recognise it or not....

    I have the honour to be, my lord, your very faithful servant,

                                        M. FARADAY.


[Sidenote: HOW SCIENCE CAN BE HONOURED.]

To Professor Andrews he wrote in 1843 in a similar strain:--

    I have always felt that there is something degrading in
    offering rewards for intellectual exertion, and that societies
    or academies, or even kings and emperors, should mingle in the
    matter does not remove the degradation, for the feeling which
    is hurt is a point above their condition, and belongs to the
    respect which a man owes to himself.... Still, I think rewards
    and honours _good_ if properly distributed; but they should be
    given for what a man has done, and not offered for what he is
    to do.

When a friend wrote to him on hearing a rumour that he had himself been
knighted, his reply, published years after in the _London Review_, was:
“I am happy that I am not a Sir, and do not intend (if it depends upon
me) to become one. By the Prussian knighthood[57] I do feel honoured;
in the other I should not.”

On one occasion he commented rather sarcastically upon the British
Government and its stinginess as compared with those of all other
civilised countries in its aids to scientific progress. This complaint
is equally justified to-day. To many it may be news that England pays
to its Astronomer Royal--who must obviously be a person of very high
scientific qualifications--a salary less than those paid to the five
assistant under-secretaries in the Colonial and Foreign Offices; less
than that paid to the sergeants-at-arms in the Houses of Parliament;
less than that paid to the person appointed Director of Clothing in the
War Office. Enlightened England!

Faraday did not deem the pursuit of science to be necessarily
incompatible with what he termed “professional business”--that
is, expert work. Until the day when he abandoned all professional
engagements, so as to devote himself to researches, he had been
receiving a considerable and growing income from this source. But
he objected to the indignities to which this work exposed him from
lawyers, who would not understand that he took no partisan view. He
could not endure the browbeating of cross-examining counsel. The late
Lord Cardwell was witness to a gentle but crushing reproof which he
once administered to a barrister who attempted to bully him. A writer
in the _British Quarterly Review_ attributes to a specific case his
determination to cease expert work.

    He gave evidence once in a judicial case, when the scientific
    testimony, starting from given premises, was so diverse that
    the presiding judge, in summing up launched something like a
    reproach at the scientific witnesses. “Science has not shone
    this day,” was his lordship’s remark. From that time forth
    no one ever saw Faraday as a scientific witness before a law
    tribunal.

[Sidenote: UNIVERSITY DEGREES IN SCIENCE.]

Amongst the honours received by Faraday there was one of which,
in 1838, he said that he felt it equal to any other he had
received--namely, that of Member of the Senate of the University of
London, to which position he was nominated in 1836 by the Crown. For
twenty-seven years he remained a senator, and when, in 1859, the
project for creating degrees in science was on foot, he was one of
the committee who drew up a report and scheme of examination for the
Senate. To the Rev. John Barlow he wrote on this matter:--

    The Senate of the University accepted and approved of the
    report of the Committee for Scientific Degrees, so that that
    will go forward (if the Government approve), and will come into
    work next year. It seems to give much satisfaction to all who
    have seen it, though the subject is beset with difficulties;
    for when the depth and breadth of science came to be
    considered, and an estimate was made of how much a man ought to
    know to obtain a right to a degree in it, the amount in words
    seemed to be so enormous as to make me hesitate in demanding it
    from the student; and though in the D.S. one could divide the
    matter and claim eminence in one branch of science, rather than
    good general knowledge in all, still in the B.S., which is a
    progressive degree, a more extended though a more superficial
    acquaintance seemed to be required. In fact, the matter is
    so new, and there is so little that can serve as a previous
    experience in the founding and arranging these degrees, that
    one must leave the whole endeavour to shape itself as the
    practice and experience accumulates.

When, in 1863, his feebleness impelled him to resign this position, he
wrote to Dr. Carpenter:--

    The position of a senator is one that should not be held by
    an inactive man to the exclusion of an active one. It has
    rejoiced my heart to see the progress of the University, and
    of education under its influence and power; and that delight I
    hope to have so long as life shall be spared to me.

He had little sympathy with either text-book science or with mere
examinations. “I have far more confidence,” he wrote, “in the one man
who works mentally and bodily at a matter than in the six who merely
talk about it. Nothing is so good as an experiment which, whilst
it sets error right, gives an absolute advancement in knowledge.”
In another place he wrote:--“Let the imagination go, guarding it
by judgment and principles, but holding it in and directing it by
experiment.” For book-learned chemistry and mere chemical theory, apart
from experimental facts, he had an undisguised contempt. Writing to
General Portlock on the subject of chemical education, he stated that
he had been one of the Senate of the University of London appointed to
consider especially the best method of examination. They had decided
on examination by papers, accompanied by _vivâ voce_. “We think,” he
added, “that no numerical value can be attached to the questions,
because everything depends on _how they are answered_.” Then, referring
to the teaching at Woolwich, he says, “My instructions always have
been to look to the note-books for the result.” “Lectures alone cannot
be expected to give more than a general idea of this most extensive
branch of science, and it would be too much to expect that young men
who at the utmost hear only fifty lectures on chemistry should be
able to answer with much effect, in writing, to questions set down on
paper, when we know by experience that daily work for eight hours in
_practical laboratories_ for _three months_ does not go very far to
confer such ability.”

[Sidenote: SCIENCE AND THE UNIVERSITIES.]

He had, at an earlier date, declined to be appointed as examiner in the
University. He had previously declined the professorship of chemistry
in University College; and he had also declined the chemical chair in
the University of Edinburgh. This was not, however, from any want of
sympathy with university work, or failure to appreciate the ideal of a
university as a seat of learning. Writing to Tyndall, in 1851, about
another university--that at Toronto--he said: “I trust it is a place
where a man of science and a true philosopher is required, and where,
in return, such a man would be nourished and cherished in proportion to
his desire to advance natural knowledge.”

At the same time he had an exceeding repugnance to the custom of
expecting candidates for professorial chairs to produce “testimonials”
of their qualifications. When his intimate friend Richard Phillips was
a candidate for the very chair which Faraday refused at University
College, Faraday declined on principle to give a testimonial. “I should
indeed have thought,” he added, “his character had been known to
be such that it would rather have been degraded than established by
certificates.”

Similarly, in 1851, he told Tyndall, then an applicant for the Chair of
Physics at Toronto, that he had in every case refused for many years
past to give any on the application of candidates. “Nevertheless,” he
added, “I wish to say that when I am asked about a candidate by those
who have the choice or appointment, I never refuse to answer.”

[Sidenote: SCIENCE IN EDUCATION.]

On general education, Faraday’s ideas were much in advance of his
time. From the epoch when as a young man he lectured to the City
Philosophical Society on the means of obtaining knowledge and on mental
inertia, down to the close of his career, he consistently advocated
the cultivation of the experimental method and the use of science as
a means of training the faculties. A concise account of his views is
to be found in the lecture he gave in 1854 before the Prince Consort
on “Mental Education,” a lecture which prescribes the self-educating
discipline of scientific study and experiment as a means of correcting
deficiency of judgment. It included a powerful plea for suspense of
judgment and for the cultivation of the faculty of proportionate
judgment. In 1862 he was examined at some length by the Royal
Commissioners upon Public Schools. With them he pleaded strongly for
the introduction of science into the school curricula; and when asked
at what age it might be serviceable to introduce science-teaching,
replied: “I think one can hardly tell that until after experience for
some few years. All I can say is this that at my juvenile lectures at
Christmas time I have never found a child too young to understand
intelligently what I told him; they came to me afterwards with
questions which proved their capability.”

One passage from the close of a lecture given in 1858 deserves to be
recorded for its fine appreciation of “the kind of education which
science offers to man”:--

    It teaches us to be neglectful of nothing, not to despise
    the _small_ beginnings--they precede of necessity _all great
    things_.... It teaches a continual comparison of the _small
    and great_, and that under differences almost approaching
    the infinite, for the small as often contains the great in
    principle as the great does the small; and thus the mind
    becomes comprehensive. It teaches to deduce principles
    carefully, to hold them firmly, or to suspend the judgment,
    to discover and obey _law_, and by it to be bold in applying
    to the greatest what we know of the smallest. It teaches us,
    first by tutors and books, to learn that which is already known
    to others, and then by the light and methods which belong to
    science to learn for ourselves and for others; so making a
    fruitful return to man in the future for that which we have
    obtained from the men of the past. Bacon in his instruction
    tells us that the scientific student ought not to be as the
    ant, who gathers merely, nor as the spider who spins from her
    own bowels, but rather as the bee who both gathers and produces.

    All this is true of the teaching afforded by any part of
    physical science. Electricity is often called wonderful,
    beautiful; but it is so only in common with the other forces of
    nature. The beauty of electricity or of any other force is not
    that the power is mysterious, and unexpected, touching every
    sense at unawares in turn, but that it is under _law_, and that
    the taught intellect can even now govern it largely. The human
    mind is placed above, and not beneath it, and it is in such a
    point of view that the mental education afforded by science is
    rendered super-eminent in dignity, in practical application and
    utility; for by enabling the mind to apply the natural power
    through law, it conveys the gifts of God to man.

[Sidenote: ON MATHEMATICS.]

A peculiar interest attaches to Faraday’s attitude towards the study
of mathematics. He who had never had any schooling beyond the common
school of his parish had not advanced beyond the simplest algebra in
his mastery over symbolic reasoning. Several times in his “Experimental
Researches” he deplores what he termed “my imperfect mathematical
knowledge.” Of Poisson’s theory of magnetism he said: “I am quite unfit
to form a judgment.” Dr. Scoffern repeats a pleasantry of Faraday’s
having on a certain occasion boasted that he had once in the course of
his life performed a mathematical operation--when he turned the handle
of Babbage’s calculating machine. Certain it is that he went through
the whole of his magnificent researches without once using even a sine
or a cosine, or anything more recondite than the simple rule-of-three.
He expressed the same kind of regret at his unfamiliarity with the
German language--“the language of science and knowledge,” as he
termed it in writing to Du Bois Reymond--which prevented him from
reading the works of Professor “Ohms.” Nevertheless he valued the
mathematical powers of others, and counselled Tyndall to work out his
experimental results, “so that the mathematicians may be able to take
it up.” Yet he never relaxed his preference for proceeding along the
lines of experimental investigation. His curious phrase (p. 239) as
to his pique respecting mathematics is very significant, as is also
his note of jubilation in his letter to Phillips (p. 117) at finding
that pure experiment can successfully rival mathematics in unravelling
the mysteries which had eluded the efforts of Poisson and Arago.
He himself attributed to his defective memory his want of hold upon
symbolic reasoning. To Tyndall he wrote in 1851, when thanking him for
a copy of one of his scientific memoirs:--

    Such papers as yours make me feel more than ever the loss of
    memory I have sustained, for there is no reading them, or at
    least retaining the argument, under such deficiency.

    Mathematical formulæ more than anything require quickness and
    surety in receiving and retaining the true value of the symbols
    used; and when one has to look back at every moment to the
    beginning of a paper, to see what H or A or B mean, there is
    no making way. Still, though I cannot hold the whole train of
    reasoning in my mind at once, I am able fully to appreciate
    the value of the results you arrive at, and it appears to me
    that they are exceedingly well established and of very great
    consequence. These elementary laws of action are of so much
    consequence in the development of the nature of a power which,
    like magnetism, is as yet new to us.

Again to Clerk Maxwell, in 1857, he wrote:--

    There is one thing I would be glad to ask you. When a
    mathematician engaged in investigating physical actions and
    results has arrived at his own conclusions, may they not be
    expressed in common language as fully, clearly, and definitely
    as in mathematical formulæ? If so, would it not be a great boon
    to such as we to express them so--translating them out of their
    hieroglyphics that we also might work upon them by experiment?
    I think it must be so, because I have always found that you
    could convey to me a perfectly clear idea of your conclusions,
    which, though they may give me no full understanding of the
    steps of your process, gave me the results neither above nor
    below the truth, and so clear in character that I can think and
    work from them.

    If this be possible, would it not be a good thing if
    mathematicians, writing on these subjects, were to give us
    their results in this popular useful working state as well as
    in that which is their own and proper to them?

The achievement of Faraday in finding for the expression of
electromagnetic laws means which, though not symbolic, were simple,
accurate, and in advance of the mathematics of his time, has been
alluded to on page 217. Liebig, in his discourse on “Induction and
Deduction,” refers to Faraday thus:--

    I have heard mathematical physicists deplore that Faraday’s
    records of his labours were difficult to read and understand,
    that they often resembled rather abstracts from a diary. But
    the fault was theirs, not Faraday’s. To physicists who have
    approached physics by the road of chemistry, Faraday’s memoirs
    sound like an admirably beautiful music.

[Sidenote: MAXWELL AND VON HELMHOLTZ.]

Von Helmholtz, in his Faraday lecture of 1881, has also touched on this
aspect.

    Now that the mathematical interpretation of Faraday’s
    conceptions regarding the nature of electric and magnetic
    forces has been given by Clerk Maxwell, we see how great a
    degree of exactness and precision was really hidden behind the
    words which to Faraday’s contemporaries appeared either vague
    or obscure; and it is in the highest degree astonishing to
    see what a large number of general theorems, the methodical
    deduction of which requires the highest powers of mathematical
    analysis, he found by a kind of intuition, with the security of
    instinct, without the help of a single mathematical formula.

Two other passages from Von Helmholtz are worthy of being added:--

    And now, with a quite wonderful sagacity and intellectual
    precision, Faraday performed in his brain the work of a great
    mathematician without using a single mathematical formula.
    He saw with his mind’s eye that magnetised and dielectric
    bodies ought to have a tendency to contract in the direction
    of the lines of force, and to dilate in all directions
    perpendicular to the former, and that by these systems of
    tensions and pressures in the space which surrounds electrified
    bodies, magnets, or wires conducting electric currents, all
    the phenomena of electrostatic, magnetic, electromagnetic
    attraction, repulsion, and induction could be explained,
    without recurring at all to forces acting directly at a
    distance. This was the part of his path where so few could
    follow him; perhaps a Clerk Maxwell, a second man of the same
    power and independence of intellect, was needed to reconstruct
    in the normal methods of science the great building the plan of
    which Faraday had conceived in his mind, and attempted to make
    visible to his contemporaries.

    Nobody can deny that this new theory of electricity and
    magnetism, originated by Faraday and developed by Maxwell, is
    in itself well consistent, in perfect and exact harmony with
    all the known facts of experience, and does not contradict any
    one of the general axioms of dynamics, which have been hitherto
    considered as the fundamental truths of all natural science,
    because they have been found valid, without any exception, in
    all known processes of nature.

And, after dealing with the phenomena discussed by Faraday, Von
Helmholtz adds these pregnant words:--

    Nevertheless, the fundamental conceptions by which Faraday
    was led to these much-admired discoveries have not received
    an equal amount of consideration. They were very divergent
    from the trodden path of scientific theory, and appeared
    rather startling to his contemporaries. His principal aim was
    to express in his new conceptions only facts, with the least
    possible use of hypothetical substances and forces. This was
    really an advance in general scientific method, destined to
    purify science from the last remnants of metaphysics. Faraday
    was not the first, and not the only man, who had worked in
    this direction, but perhaps nobody else at his time did it so
    radically.

Clerk Maxwell said of him:

    The way in which Faraday made use of his lines of force in
    co-ordinating the phenomena of electric induction shows him to
    have been a mathematician of high order, and one from whom the
    mathematicians of the future may derive valuable and fertile
    methods.

It is fitting to include in this review of Faraday’s place in relation
to the mathematical side of physics some words of Lord Kelvin, taken
from his preface to the English edition of Hertz’s “Electric Waves”:--

    Faraday, with his curved lines of electric force, and
    his dielectric efficiency of air and of liquid and solid
    insulators, resuscitated the idea of a medium through which,
    and not only through which but _by_ which, forces of attraction
    or repulsion, seemingly acting at a distance, are transmitted.

    The long struggle of the first half of the eighteenth century
    was not merely on the question of a medium to serve for
    gravific mechanism, but on the correctness of the Newtonian
    law of gravitation as a matter of fact, however explained. The
    corresponding controversy in the nineteenth century was very
    short, and it soon became obvious that Faraday’s idea of the
    transmission of electric force by a medium not only did not
    violate Coulomb’s law of relation between force and distance,
    but that, if real, it must give a thorough explanation of that
    law. Nevertheless, after Faraday’s discovery of the different
    specific inductive capacities of different insulators, twenty
    years passed before it was generally accepted in Continental
    Europe. But before his death, in 1867, he had succeeded in
    inspiring the rising generation of the scientific world
    with something approaching to faith that electric force is
    transmitted by a medium called ether, of which, as had been
    believed by the whole scientific world for forty years, light
    and radiant heat are transverse vibrations. Faraday himself
    did not rest with this theory of electricity alone. The very
    last time I saw him at work at the Royal Institution was in
    an underground cellar, which he had chosen for freedom from
    disturbance, and he was arranging experiments to test the
    time of propagation of magnetic force from an electromagnet
    through a distance of many yards of air to a fine steel needle,
    polished to reflect light; but no result came from those
    experiments. About the same time, or soon after, certainly not
    long before the end of his working time, he was engaged (I
    believe at the Shot Tower, near Waterloo Bridge, on the Surrey
    side) in efforts to discover relations between gravity and
    magnetism, which also led to no result.

[Sidenote: KELVIN’S APPRECIATION.]

Lord Kelvin, who was himself the first to perceive that Faraday’s ideas
were not inconsistent with mathematical expression, and to direct Clerk
Maxwell and others to this view, had, in 1854, delighted the old man
by bringing mathematical support to the conception of lines of force.
In 1857 he sent to Faraday a copy of one of his papers, and received
in acknowledgment a letter of warm encouragement, which, however, does
not appear to have been preserved. Lord Kelvin’s reply is its own best
commentary:--

    Such expressions from you would be more than a sufficient
    reward for anything I could ever contemplate doing in science.
    I feel strongly how little I have done to deserve them, but
    they will encourage me with a stronger motive than I have
    ever had before to go on endeavouring to see in the direction
    you have pointed, which I long ago learned to believe is the
    direction in which we must look for a deeper insight into
    nature.




CHAPTER VIII

RELIGIOUS VIEWS.


The name of Glasites or Sandemanians is given to a small sect of
Christians which separated from the Scottish Presbyterian Church
about 1730 under the leadership of the Rev. John Glas. Most of the
congregations which sprang up in England were formed in consequence
of the dissemination of the writings and by the preaching of Robert
Sandeman, son-in-law and successor of Glas. Hence the double name. The
Sandemanian Church in London was constituted about 1760. It still has
a chapel in Barnsbury, though the sect as a whole--never numerous--has
dwindled to a small remnant.[58] The religious census of 1851 showed
but six congregations in England and six in Scotland. As it never was
a proselytising body, it is probable that it has diminished since that
date. John Glas was deposed in 1728 by the Presbyterian Courts from his
position as minister in the Scottish Church, because he taught that
the Church should be governed only by the doctrines of Christ and His
apostles, and not be subject to any League or Covenant. He held that
the formal establishment by any nation of a professed religion was
the subversion of primitive Christianity; that Christ did not come to
establish any worldly authority, but to give a hope of eternal life to
His people whom He should choose of His own sovereign will; that “the
Bible,” and it alone, with nothing added to it nor taken away from it
by man, was the sole and sufficient guide for each individual, at all
times and in all circumstances; that faith in the divinity and work
of Christ is the gift of God, and that the evidence of this faith is
obedience to the commandment of Christ.

[Sidenote: THE SANDEMANIAN CREED.]

The tenets of Glas are somewhat obscure and couched in mystical
language. They prescribe a spiritual union which binds its members into
one body as a Church without its being represented by any corresponding
outward ecclesiastical polity. He died in 1773. Sandeman, who spent
most of his life in preaching these doctrines, died about the same time
in New England. He caused to be inscribed on his tomb that “he boldly
contended for the ancient faith that the bare death of Jesus Christ,
without a deed or thought on the part of man, is sufficient to present
the chief of sinners spotless before God.”

[Sidenote: A PRIMITIVE CHURCH.]

The Sandemanians try--so far as modern conditions permit--to live up
to the practice of the Christian Church as it was in the time of the
Apostles. At their chapel they “broke bread” every Lord’s day in the
forenoon, making this a common meal between the morning and afternoon
services, and taking their places by casting lots. And weekly, at
their simple celebration of the Lord’s Supper at the close of the
afternoon service, before partaking, they collect money for the support
of the poor and for expenses. In some places they dined together at
one another’s houses instead of at the chapel. “They esteem the lot
as a sacred thing. The washing of the feet is also retained: not, it
would seem, on any special occasion, but the ablution is performed
‘whenever it can be an act of kindness to a brother to do so.’ Another
peculiarity of this religious body is their objection to second
marriages.”[59] Members are received into the Church on the confession
of sin and profession of faith made publicly at one of the afternoon
services. In admitting a new member they give the kiss of charity.
They deem it wrong to save up money; “the Lord will provide” being an
essential item of faith. Traces of this curious fatalism may be found
in one of Faraday’s letters to his wife (p. 52). He seems always to
have spent his surplus income on charity. The Sandemanians have neither
ordained ministers nor paid preachers. In each congregation, however,
there are chosen elders (presbyters or bishops), of whom there must
always be a plurality, and of whom two at least must be present at
every act of discipline. The elders take it in turns to preside at the
worship, and are elected by the unanimous choice of the congregation.
The sole qualification for this office, which is unpaid, is that
earnestness of purpose and sincerity of life which would have been
required in Apostolic times for the office of bishop or presbyter. No
difference of opinion is tolerated, but is met by excommunication,
which amongst families so connected by marriage produces much
unhappiness, since they hold to the Apostle’s injunction, “With such an
one, no, not to eat.”

The foregoing summary is needed to enable the reader to comprehend
the relationship of Faraday to this body. His father and grandfather
had belonged to this sect. In 1763 there was a congregation at Kirkby
Stephen (the home of Faraday’s mother) numbering about thirty persons;
and there appears to have been a chapel--now used as a barn--in
Clapham. A strong religious feeling had been dominant in the Faraday
family through the preceding generation. James Faraday, on his removal
to London, there joined the Sandemanian congregation, which at that
time met in a small chapel in St. Paul’s Alley, Barbican, since pulled
down. It had, when founded in 1762, held its first meetings in the hall
of the Glovers’ Company, and later in Bull and Mouth Street, till 1778.
James Faraday’s wife, mother of Michael Faraday, never formally joined
the Sandemanian Church, though a regular attendant of the congregation.
Michael Faraday was from a boy brought up in the practice of attending
this simple worship, and in the atmosphere of this primitive religious
faith. Doubtless such surroundings exercised a moulding influence on
his mind and character. The attitude of abstinence from attempts to
proselytise, on the part of the church, finds its reflex in Faraday’s
habitual reticence, towards all save only the most intimate of friends,
on matters of religious faith. “Never once,” says Professor Tyndall,
“during an intimacy of fifteen years, did he mention religion to me,
save when I drew him on to the subject. He then spoke to me without
hesitation or reluctance; not with any apparent desire to ‘improve the
occasion,’ but to give me such information as I sought. He believed the
human heart to be swayed by a power to which science or logic opened no
approach; and right or wrong, this faith, held in perfect tolerance of
the faiths of others, strengthened and beautified his life.”

[Sidenote: HIS PROFESSION OF FAITH.]

Of his spiritual history down to the time of his marriage very little
is known, for he made no earlier profession of faith. It is not to
be supposed that he who was so scrupulous of truth, so single-minded
in every relation of life, would accept the religious belief of his
fathers without satisfying his conscience as to the rightness of its
claims. Yet none of his letters or writings of that period show any
trace[60] of that stress of soul through which at one time or another
every sincere and earnest seeker after truth must pass before he
finds anchorage. Certain it is that he clung with warm attachment to
the little self-contained sect amongst whom he had been brought up.
Its influence, though contracting his activities by precluding all
Christian communion or effort outside their circle, and cutting him
off from so much that other Christian bodies hold good, fenced him
effectually from dreams of worldliness, and furnished him with that
very detachment which was most essential to his scientific pursuits.
One month after his marriage he made his confession of sin and
profession of faith before the Sandemanian Church. It was an act of
humility the more striking in that it was done without any consultation
with his wife, to whom he was so closely attached, and who was already
a member of the congregation. When she asked him why he had not told
her what he was about to do, he replied: “That is between me and my
God.”

In 1844 he wrote to Lady Lovelace as follows:--

“You speak of religion, and here you will be sadly disappointed in
me. You will perhaps remember that I guessed, and not very far aside,
your tendency in this respect. Your confidence in me claims in return
mine to you, which indeed I have no hesitation in giving on fitting
occasions, but these I think are very few, for in my mind religious
conversation is generally in vain. _There is no philosophy in my
religion._ I am of a very small and despised sect of Christians, known,
if known at all, as Sandemanians, and our hope is founded on the faith
that is in Christ. But though the natural works of God can never by
any possibility come in contradiction with the higher things that
belong to our future existence, and must with everything concerning
Him ever glorify Him, still I do not think it at all necessary to tie
the study of the natural sciences and religion together, and, in my
intercourse with my fellow creatures, that which is religious and that
which is philosophical have ever been two distinct things.”

His own views were stated by himself at the commencement of a lecture
on _Mental Education_ in 1854:--

    High as man is placed above the creatures around him, there
    is a higher and far more exalted position within his view;
    and the ways are infinite in which he occupies his thoughts
    about the fears, or hopes, or expectations of a future life.
    I believe that the truth of that future cannot be brought to
    his knowledge by any exertion of his mental powers, however
    exalted they may be; that it is made known to him by other
    teaching than his own, and is received through simple belief
    of the testimony given. Let no one suppose for a moment that
    the self-education I am about to commend, in respect of the
    things of this life, extends to any considerations of the hope
    set before us, as if man by reasoning could find out God. It
    would be improper here to enter upon this subject further than
    to claim an absolute distinction between religious and ordinary
    belief. I shall be reproached with the weakness of refusing to
    apply those mental operations which I think good in respect
    of high things to the very highest. I am content to bear the
    reproach.

One of his friends wrote: “When he entered the meeting-house he left
his science behind, and he would listen to the prayer and exhortation
of the most illiterate brother of his sect with an attention which
showed how he loved the word of truth, from whomsoever it came.”

[Sidenote: AS ELDER AND PREACHER.]

“The most remarkable event,” says Dr. Bence Jones, “of his life in 1840
was his election as an elder of the Sandemanian Church. During that
period when in London he preached on alternate Sundays.” This was not
an entirely new duty, for he had been occasionally called upon by the
elders, from the date of his admission in 1821, to exhort the brethren
at the week-day evening meetings, or to read the Scriptures in the
congregation. Bence Jones says that, though no one could lecture like
Faraday, many might preach with more effect. The eager and vivacious
manner of the lecture-room was exchanged for a devout earnestness
that was in complete contrast. His addresses have been described as a
patchwork of texts cited rapidly from the Old and New Testaments; and
they were always extempore, though he prepared careful notes on a piece
of card beforehand. Of these, samples are given in Bence Jones’s “Life
and Letters.” His first discourse as an elder was on Matt. xi. 28–30,
dilating on Christ’s character and example. “Learn of Me.” The ground
of humility of Christians must be the infinite distance between them
and their Pattern. He quoted 1 John ii. 6; 1 Peter ii. 21; Phil. iii.
17; 1 Cor. xi. 1; and 1 Cor. xiv. 1.

An exceedingly vivid view of Faraday as elder of the Church was given
in 1886[61] by the late Mr. C. C. Walker, himself at one time a member
of the Sandemanian congregation in London; a congregation, moreover,
which included several persons of distinction--Cornelius Varley, the
engraver, and George Barnard, the water-colour painter.

    At Faraday’s chapel there was a presiding elder, supported by
    the rest of the elders on two rows of seats elevated across
    the end of the chapel, one row above the other. The ground
    floor was filled with the old-fashioned high pews, and there
    was a gallery above on both sides, also with pews. Faraday sat
    in a pew on the ground floor, about the middle. There was a
    large table on the floor of the chapel in front of the elders’
    seats. The presiding elder usually preached. Such was the place
    Faraday worshipped in, situated at the end of a narrow dirty
    court, surrounded by squalid houses of the poorest of the poor,
    and so little known that although I knew every street, lane
    and alley of the whole district, and this alley itself, at the
    bottom of which the chapel was, I never knew of the existence
    of the meeting-house till I learned about thirty-five years
    ago that there was a chapel there to which the world-renowned
    Faraday not only went, but where he preached. This led me to
    make a search, and to my great delight, I found it, though with
    some difficulty. Although the neighbourhood was uncleanly, not
    so was the interior of the chapel, nor the dining room, with
    its tables and forms, all of which were spotless.

    Faraday’s father was a blacksmith, and worshipped here. He
    brought up his family religiously, and Faraday from his
    earliest days attended the chapel. Here he met Miss Barnard,
    his future wife. Mr. Barnard was a respectable “working
    silversmith,” as manufacturing silversmiths were then called,
    to distinguish them from the shopkeepers who then, as now,
    called themselves “silversmiths,” though frequently making none
    of the goods they sell. His manufactory was for a time at Amen
    Court, Paternoster Row; afterwards it was removed to a large
    building erected by the firm at Angel Street, near the General
    Post Office, and the business has since been carried on by the
    sons and grandsons.

    [Sidenote: RELIGIOUS SERVICE.]

    Mr. Barnard and his family worshipped at the Sandemanian
    Chapel. To this chapel Faraday walked every Sunday morning from
    his earliest days; he never kept a carriage, and on religious
    principles would not hire a cab or omnibus on the Lord’s
    day.[62]

    The service commenced at eleven in the morning and lasted till
    about one, after which the members--“brothers and sisters,”
    as they called each other--had their midday meal “in common”
    in the room attached to the chapel, which has already been
    referred to. The afternoon worship usually ended about five
    o’clock, after partaking of the Lord’s Supper. The services
    were very much like those of the Congregationalists, and
    consisted of extempore prayers, hymns, reading the Scripture,
    and a sermon, usually by the presiding elder. Faraday had been
    an elder for a great many years, and for a considerable time
    was the presiding elder, and consequently preached; but during
    this time relinquished his office. There was one peculiarity
    in the service; the Scriptures were not read by the presiding
    elder, but he called on one of the members to read; and when
    Faraday was there--which he always was when in London--the
    presiding elder named “Brother Michael Faraday,” who then
    left his pew, passing along the aisle, out of the chapel, up
    the stairs at the back, and reappeared behind the presiding
    elder’s seat, who had already opened the large Bible in front
    of him, and pointed out the chapter to be read. It was one of
    the richest treats that it has been my good fortune to enjoy to
    hear Faraday read the Bible. The reader was quite unaware what
    he was to read until it was selected and when one chapter of
    the Old Testament was finished another would be given, probably
    from the New Testament. Usually three chapters were read, and
    sometimes four, in succession; but if it had been half a dozen
    there would have been no weariness, for the perfection of the
    reading, with its clearness of pronunciation, its judicious
    emphasis, the rich musical voice, and the perfect charm of
    the reader, with his natural reverence, made it a delight to
    listen. I have heard most of those who are considered our best
    readers in church and chapel, but have never heard a reader
    that I considered equal to Faraday.

    At this distance of time his tones are always in my ears.

       *       *       *       *       *

    I was told by members of the chapel that he was most assiduous
    in visiting the poorer brethren and sisters at their own homes,
    comforting them in their sorrows and afflictions, and assisting
    them from his own purse. Indeed, they said, he was continually
    pressed to be the guest of the high and noble (which we may
    well believe), but he would, if possible, decline, preferring
    to visit some poor sister in trouble, assist her, take a cup
    of tea with her, read the Bible and pray. Though so full of
    religion, he was never obtrusive with it; it was too sacred a
    thing.

Tyndall has preserved another vivid reminiscence of Faraday’s inner
life, which he wrote down after one of the earliest dinners which he
had in the Royal Institution.

“At two o’clock he came down for me. He, his niece, and myself formed
the party. ‘I never give dinners,’ he said; ‘I don’t know how to give
dinners; and I never dine out. But I should not like my friends to
attribute this to a wrong cause. I act thus for the sake of securing
time for work, and not through religious motives as some imagine.’ He
said grace. I am almost ashamed to call his prayer a ‘saying’ of grace.
In the language of Scripture, it might be described as the petition
of a son into whose heart God had sent the Spirit of His Son, and who
with absolute trust asked a blessing from his Father. We dined on
roast beef, Yorkshire pudding, and potatoes, drank sherry, talked of
research and its requirements, and of his habit of keeping himself free
from the distractions of society. He was bright and joyful--boylike,
in fact, though he is now sixty-two. His work excites admiration, but
contact with him warms and elevates the heart. Here, surely, is a
strong man. I love strength, but let me not forget the example of its
union with modesty, tenderness, and sweetness, in the character of
Faraday.”

There is a story told by the Abbé Moigno that one day at Faraday’s
request he introduced him to Cardinal Wiseman. In the frank interview
which followed, the Cardinal did not hesitate to ask Faraday whether,
in his deepest conviction, he believed all the Church of Christ, holy,
catholic, and apostolic, was shut up in the little sect in which he was
officially an elder. “Oh, no!” was Faraday’s reply; “but I do believe
from the bottom of my soul that Christ is with us.”

[Sidenote: ELDERSHIP INTERRUPTED.]

The course of Faraday’s eldership was, however, interrupted. It was
expected of an elder that he should attend every Sunday. One Sunday
he was absent. When it was discovered that his absence was due to his
having been “commanded” to dine with the Queen at Windsor, and that so
far from expressing penitence, he was prepared to defend his action,
his office became vacant. He was even cut off from ordinary membership.
Nevertheless, he continued for years to attend the meetings just as
before. He would even return from the provincial meetings of the
British Association to London for the Sunday, so as not to be absent.
In 1860 he was received back as an elder, which office he held again
for about three years and a half, and finally resigned it in 1864.

It is doubtful whether Faraday ever attempted to form any connected
ideas as to the nature or method of operation of the Divine government
of the physical world, in which he had such a whole-souled belief.
Newton has left us such an attempt. Kant in his own way has put forward
another. So did Herschel; and so in our time have the authors of “The
Unseen Universe.” To Faraday all such “natural theology” would have
seemed vain and aimless. It was no part of the lecturer on natural
philosophy to speculate as to final causes behind the physical laws
with which he dealt. Nor, on the other hand, was it the slightest use
to the Christian to inquire in what way God ruled the universe: it was
enough that He did rule it.

[Sidenote: RELIGION AND SCIENCE.]

Faraday’s mental organisation, which made it possible for him to
erect an absolute barrier between his science and his religion,
was an unusual one. The human mind is seldom built in such rigid
compartments that a man whose whole life is spent in analysing,
testing, and weighing truths in one department of knowledge, can cut
himself off from applying the same testing and inquiring processes
in another department. The founder of the sect had taught them that
the Bible alone, with nothing added to it or taken away from it by
man, was the only and sufficient guide for the soul. Apparently
Faraday never admitted the possibility of human flaw in the printing,
editing, translation, collation, or construction of the Bible. He
apparently never even desired to know how it compared with the oldest
manuscripts, or what was the evidence for the authenticity of the
various versions. Having once accepted the views of his sect as to the
absolute inspiration of the English Bible as a whole, he permitted no
subsequent question to be raised as to its literal authority. Tyndall
once described this attitude of mind in his own trenchant way by saying
that when Faraday opened the door of his oratory he closed that of his
laboratory. The saying may seem hard, but it is essentially true. To
few indeed is such a limitation of character possible: possibly it may
be unique. We may reverence the frank single-minded simplicity of soul
which dwelt in Faraday, and may yet hold that, whatever limitation
was right for him, others would do wrong if they refused to bring
the powers of the mind--God-given as they believe--to bear upon the
discovery of truth in the region of Biblical research. Yet may none of
them dream of surpassing in transparent honesty of soul, in genuine
Christian humility, in the virtues of kindness, earnestness, and
sympathetic devotion, the great and good man who denied himself that
freedom.




FOOTNOTES


[1] Faraday’s usual place of work at bookbinding was a little room on
the left of the entrance. (_See_ the story of his visit there with
Tyndall in after years, as narrated in Tyndall’s “Faraday,” p. 8.)

[2] Still preserved in Faraday’s Diploma-book, now in the possession of
the Royal Society.

[3] An account of this machine will be found in the _Argonaut_, vol.
ii., p. 33.

[4] “When he [Faraday] was young, poor, and altogether unknown,
Masquerier was kind to him; and now that he is a great man he does not
forget his old friend.”--Diary of H. Crabb Robinson, vol. iii., p. 375.

[5] He always sat in the gallery over the clock.

[6] See Dr. Paris’s “Life of Davy,” vol. ii., p. 2; or Bence Jones’s
“Life and Letters of Faraday,” vol. i., p. 47.

[7] His duties as laid down by the managers were these:--“To attend
and assist the lecturers and professors in preparing for, and during
lectures. Where any instruments or apparatus may be required, to attend
to their careful removal from the model-room and laboratory to the
lecture-room, and to clean and replace them after being used, reporting
to the managers such accidents as shall require repair, a constant
diary being kept by him for that purpose. That in one day in each week
he be employed in keeping clean the models in the repository, and that
all the instruments in the glass cases be cleaned and dusted at least
once within a month.”

[8] The City Philosophical Society was given up at the time when
Mechanics’ Institutes were started in London, Tatum selling his
apparatus to that established in Fleet Street, the forerunner of the
Birkbeck Institution. Many of the City Society’s members joined the
Society of Arts.

[9] Two passages may be quoted. “Finally, Sir H. has no valet except
myself ... and ’tis the name more than the thing which hurts.” “When I
return home, I fancy I shall return to my old profession of bookseller,
for books still continue to please me more than anything else.”

[10] The meeting at which it was actually originated was held under the
presidency of Sir Joseph Banks, P.R.S., nominally as a meeting for the
_Assistance of the Poor!_

[11] A writer in the _Quarterly Journal of Science_ for 1868, p. 50,
says: “We have reason to know that Davy was slightly annoyed that the
certificate proposing Faraday for election should have originated with
Richard Phillips, and that he should not have been consulted before
that gentleman was allowed to take the matter in hand.” This is absurd,
because the President was by long-standing etiquette debarred from
signing the certificates of any but foreign members, as the certificate
book of the Royal Society attests.

[12] See p. 12.

[13] Liddon’s “Life of E. B. Pusey” (1893), p. 219.

[14] For this information and many particulars of this transaction I am
indebted to Dr. J. H. Gladstone, F.R.S.

[15] “It was probably in a four-wheeled velocipede that Faraday was
accustomed, some thirty years ago, to work his way up and down the
steep roads near Hampstead and Highgate. This machine appears to have
been of his own construction, and was worked by levers and a crank
axle in the same manner as the rest of the four-wheeled class.”--_The
Velocipede: its past, its present, and its future._ By J. F. B. Firth.
London, 1869.

[16] Except on nickel and cobalt, which are also para-magnetic metals.

[17] For a graphic account by Hansteen of the circumstances of
Oersted’s discovery, see Bence Jones’s “Life and Letters of Faraday,”
vol. ii. p. 390.

[18] “To the effect which takes place in this conductor [or uniting
wire] and in the surrounding space, we shall give the name of the
_conflict of electricity_.”...

“From the preceding facts we may likewise collect that this conflict
performs circles; for without this condition, it seems impossible that
the one part of the uniting wire, when placed below the magnetic pole,
should drive it towards the east, and when placed above it towards the
west; for it is the nature of a circle that the motions in opposite
parts should have an opposite direction.”--H. C. OERSTED, _Ann. of
Phil._, Oct., 1820, pp. 273–276.

[19] This is an error due to haste in writing.

[20] See a paper by the author in the _Philosophical Magazine_ for
June, 1895, entitled “Note on a Neglected Experiment of Ampère.”

[21] Compare Dumas, “Éloge Historique de Michel Faraday,” p. xxxiii.,
who gives the above statement. Arago’s own account to the _Académie_
differs slightly.

[22] This ring Faraday is represented as holding in his hand in the
beautiful marble statue by Foley which stands in the Entrance Hall of
the Royal Institution. The ring itself is still preserved at the Royal
Institution amongst the Faraday relics. The accompanying cut (Fig. 4)
is facsimiled from Faraday’s own sketch in his laboratory note-book.

[23] Now in the possession of the author, to whom it was given by his
kinswoman Lady Wilson, youngest daughter of Richard Phillips.

[24] The day of the Annual Meeting and election of Council of the Royal
Society.

[25] This is a slip in the description; the momentary current induced
in the secondary wire on making the current in the primary is
_inverse_: it is succeeded by a momentary _direct_ current when the
primary current is stopped.

[26] This doubtless refers to Whewell, of Cambridge, whom he was in the
habit of consulting on questions of nomenclature.

[27] A man of fashion who had, without any claim to distinction, wormed
himself into scientific society, posed as a savant, and had delivered a
high-flown oration on botany at the Royal Institution.

[28] The use of this term, as distinguished from production, to
distinguish between the primary generation of a current in a voltaic
cell, a thermopile, or a friction-machine, by chemical or molecular
action, and its indirect production without contact or communication of
any material sort, as by motion of a wire near a magnet or by secondary
influence from a neighbouring primary current while that current is
varying in strength or proximity, is exceedingly significant. Faraday’s
own meaning in adopting it is best grasped by referring to p. 1 of the
“Experimental Researches”:--

    “On the _Induction_ of Electric Currents.”... The general
    term _induction_ which, as it has been received into
    scientific language, may also, with propriety, be used to
    express the power which electrical currents may possess of
    inducing any particular state upon matter in their immediate
    neighbourhood.... I propose to call this action of the current
    from the voltaic battery _volta-electric induction_ ... but as
    a distinction in language is still necessary, I propose to call
    the agency thus exerted by ordinary magnets _magneto-electric
    or magne-electric_ induction.


[29] “Experimental Researches,” i. 25, art. 85. This copper disc is
still preserved at the Royal Institution. It was shown in action by the
author of this work, at a lecture at the Royal Institution delivered
April 11th, 1891. Fig. 6 is reproduced in facsimile from Faraday’s
laboratory note-book.

[30] “Experimental Researches,” i. art. 135.

[31] _Ib._, art. 155.

[32] _Ib._, art. 158.

[33] _Ib._, art. 219.

[34] “Experimental Researches,” i. art. 220.

[35] _Ib._, art. 222.

[36] _Ib._, iii. art. 3192.

[37] “Ann. Chim. Phys.,” li. 76, 1832.

[38] The great magnet of the Royal Society, which was at this time lent
to Mr. Christie.

[39] [Original footnote by Faraday.] By magnetic curves, I mean the
lines of magnetic force, however modified by the juxtaposition of
poles, which would be depicted by iron filings; or those to which a
very small magnetic needle would form a tangent.

[40] The entire uselessness as well as the misleading effects of
such unscientific nomenclature might well be taken to heart by those
electrophysiologists and electrotherapeutists who still indulge in the
jargon of “franklinisation,” “faradisation,” and “galvanisation.”

[41] In modern language this would be called the time-integral of
the discharge. The statement is strictly true if the galvanometer
(as was the case with Faraday’s) is one of relatively long period of
oscillation.

[42] From ἄνω _upwards_ and ὁδός _a way_; and κατά _downwards_ and ὁδός
_a way_. The words _cathode_ and _cation_ are now more usually spelled
_kathode_ and _kation_. Faraday sometimes spelled the word _cathion_
(Exp. Res. Art. 1351), as did also Whewell (Hist. of Ind. Sciences,
vol. iii. p. 166).

[43] Literally, _the travellers_, the things which are going.

[44] The term _induction_ appears to have been originally used, in
contradistinction to _contact_ or _conduction_, to connote those
effects which apparently are in the class of actions at a distance.
Thus we may have induction of a charge by a charge, or of a magnet-pole
by a magnet-pole. To these Faraday had added the induction of a current
by a current, and the induction of a current by a moving magnet. Amid
such varying adaptations of the word _induction_, there is much gain
in allotting to the electrostatic induction of charges by charges the
distinguishing name of _influence_, as suggested by Priestley.

[45] “Faraday as a Discoverer,” p. 67.

[46] Newton’s third letter to Bentley.

[47] Faraday’s definition is:--“By a _diamagnetic_, I mean a body
through which lines of magnetic force are passing, and which does not
by their action assume the usual magnetic state of iron or loadstone.”
It was thus a term strictly analogous to the term _dielectric_ used for
bodies through which lines of electric force might pass.

[48] _i.e._ Specimen No. 174. Its composition was equal parts by weight
of boracic acid, oxide of lead, and silica.

[49] Subsequent investigation has reduced this figure to about 186,400
miles per second, or about 30,000,000,000 centimetres per second.

[50] The accompanying diagram (Fig. 20) was not given by Faraday. It
was pencilled by the author more than twenty years ago in the margin
of his copy of Faraday’s “Experimental Researches,” vol. iii., p. 450,
opposite this passage.

[51] The discourse was to have been delivered by Wheatstone himself,
who, however, at the last moment, overcome by the shyness from which he
suffered to an almost morbid degree, quitted the Institution, and left
the delivery of the discourse to Faraday.

[52] The italics here are mine. S. P. T.

[53] It is right to add that what, according to the theory explained in
the text, must be the correct explanation of the peculiar phenomena of
magnetic induction depending on magnecrystallic properties was clearly
stated in the form of a conjecture by Faraday in his twenty-second
series in the following terms: “Or we might suppose that the crystal
is a little more apt for magnetic induction, or a little less apt
for diamagnetic induction, in the direction of the magnecrystallic
axis than in other directions” (Sir William Thomson, _Philosophical
Magazine_, 1851, or “Papers on Electrostatics and Magnetism,” p. 476).

[54] This is exactly Stokes’s theorem of “tubes” of force. S. P. T.

[55] The italics are mine. S. P. T.

[56] Once again did Faraday intervene in Royal Society affairs at
the crucial time when Lord Rosse was elected President in 1848. The
following excerpts from the journals of Walter White show the cause:--

“November 25th.--There have been many secret conferences this
week--much trimming and time-serving. Alas for human nature!”

“November 30th.--The eventful day, the ballot begun. Mr. Faraday made
some remarks about the list.”

[57] He was a Chevalier of the Prussian Order of Merit, also Commander
in the Legion of Honour, and Knight Commander of the Order of St.
Maurice and St. Lazarus.

[58] Faraday’s nephew, Frank Barnard, stated in 1871 that the London
congregation included amongst its members not more than twenty men,
mostly quite poor, only seven or eight of them being masters of their
own businesses, and that Faraday was for some time the wealthiest man
of the fraternity.

[59] C. M. Davies: “Unorthodox London,” page 284.

[60] A letter from his nephew, Frank Barnard, to Dr. Gladstone says:
“I believe that in his younger days he had his period of hesitation,
of questioning in that great argument. I have heard that, so alive was
he to the necessity of investigating anything that seemed important,
he visited Joanna Southcote, perhaps to learn what that woman’s
pretensions were: I think he was a mere lad at that time. But this
period once passed, he questioned no more, for the more he saw that
Nature was mighty, the more he felt that God was mightier; and to any
cavillings upon the doubts of Colenso or the reality of the Mosaic
cosmogony, I believe he would simply have replied in the apostle’s
words: ‘Is anything too hard for God?’...

“I once heard him say from the pulpit, ‘I hope none of my hearers will
in these matters listen to the thing called philosophy.’”

[61] _Manchester Guardian_, November 27.

[62] [This is not altogether accurate. Certainly in his later life
Faraday used to hire a cab to take him and Mrs. Faraday to the chapel.
S. P. T.]




INDEX


  Abbott, Benjamin, 7, 8, 97, 227;
    letters to, 7, 9, 15, 22, 25, 26, 41, 44, 228

  Acoustical researches, 136

  Action at a distance unthinkable, 128, 153, 157, 216

  Admiralty, Scientific adviser to the, 68

  Æther, the, Speculations upon, 193, 213

  Airy, Sir George, Dispute with, 269

  Aloofness from scientific organisations, 264

  Ampère, Andrée Marie:
    Meeting with, 19;
    his researches, 80, 82, 85, 105, 126

  Analyst, Faraday’s professional work as, 51, 61, 63, 274

  Anderson, Sergeant:
    engaged as assistant, 96;
    his implicit obedience, 97, 242

  Andrews, Professor T., Letter to, 273

  Apparatus, Simplicity of, 239

  Arago, F.:
    Meeting with, 34, 238;
    his notations, 106, 116, 118;
    his philosophical reserve, 107

  Armstrong, Lord, on electrification of steam, 170

  Artists amongst acquaintances, 246

  Astley’s Theatre, 51

  Athenæum Club, 59

  Atmospheric magnetism, 206, 209, 210

  Atoms or centres of force, 241

  Autobiographical notes, 8, 17, 50, 58, 70, 71, 73, 76, 223, 243


  B.

  Babbage, Charles, 107, 116, 262

  Barnard, Edward, 46

  ----, Frank, 250, 286

  ----, George, 46, 51, 74, 89, 224, 246, 294

  ----, Miss Jane, 46, 259

  ----, ---- Sarah (Mrs. Faraday), 46, 294

  Becker, Dr., Letter to, 244

  Bence Jones’s “Life and Letters of Faraday,” 7, 26, 40, 43, 48, 57,
        58, 78, 108, 199, 226, 231, 293

  Benzol, Discovery of, 94, 101

  Bidwell, S., magnetic action of light, 184

  Biographies of Faraday (_see_ PREFACE)

  Boltzmann:
    on crystalline dielectrics, 166;
    on the doctrines of Faraday and Maxwell, 216

  Bookbinding, 5, 6, 17, 249

  Bookselling, 5, 17, 26, 31

  Books by Faraday:
    “On the Means of Obtaining Knowledge,” 41;
    “Chemical Manipulations,” 101, 233;
    “On Alleged Decline of Science in England” (editor), 110;
    “Experimental Researches in Electricity and Magnetism,” 102;
    “Experimental Researches in Chemistry and Physics,” 76;
    “On the Prevention of Dry Rot in Timber,” 149;
    “Chemistry of a Candle,” 234;
    “The Forces of Nature,” 234

  Boots, a home-made pair of, 249

  Brande, W. F., Prof., 39, 57

  Breakdown in health, 170, 199, 222, 259

  British Association, 64, 224, 264, 268, 297

  Browning, Mrs. E. B., denounces Faraday, 251

  Burdett-Coutts, Baroness, Letter to, 240


  C.

  Cards, Use of, to assist memory, 7, 239

  Charge, electric, Query as to seat of, 154

  ----, The nature of an electric, 152

  Charitable gifts, 245, 296

  Chemical researches, 45, 82, 87;
    analysis of caustic lime, 76;
    new chlorine compounds, 87;
    liquefaction of chlorine, 93;
    discovery of benzol, 94;
    sulpho-naphthalic acid, 100

  Chemistry, How to examine in, 277

  Children and Faraday, 233, 235

  Chlorine, Liquefaction of, 55, 91

  Christmas lectures, 33, 37, 61, 101, 233, 234, 235, 258

  City Philosophical Society, 14, 16, 40, 41, 230

  Clerk Maxwell, J.:
    article on Faraday, 135;
    theory of conduction, 155;
    electromagnetic theory of light, 199;
    on Faraday’s conception of electric action, 217;
    letter to, on mathematics, 281

  Closing days of Faraday’s life, 259

  Coinage of new words, 116, 143, 144, 163, 188, 205

  Commonplace books, 40, 89

  Conduction, Theory of, 155

  Conservation of energy, 167, 219

  Contact theory of cells, 168

  Continent, Visits to, 16, 17, 74, 224

  Controversy, Detestation of, 268

  Convolutions of the forces of nature, 167, 172, 269, 270

  Copper disc experiment, 113

  Criticism, Uses of, 14, 231, 240, 269

  Crosse, Mrs. A., Reminiscences of, 233, 245, 270

  Crystallisation in relation to electric properties, 166, 167

  Crystals in the magnetic field, 200, 202

  Current, Conception of a, 146, 163

  Cutting the magnetic lines, 134, 213

  Crookes, Sir W., Advice to, 267


  D.

  Dalton, John, 65, 226

  Dance, Mr., gives Faraday tickets, 8;
    message to, 30

  Daniell, Prof. J. F., 64

  Davy, Sir Humphry:
    lectures of, 8, 36, 227;
    note to Faraday, 11;
    engages Faraday, 12;
    travels abroad, 17;
    his aristocratic leanings, 25;
    researches on electric arc, 37;
    invention of safety lamp, 37, 42, 269;
    writes to Faraday, 44, 45;
    misunderstanding with, 56;
    his jealousy of Faraday, 56, 59;
    his electromagnetic discovery, 80;
    and the liquefaction of chlorine, 93

  Davy-Faraday laboratory, The, 36

  De la Rive, Auguste, 29, 66, 105, 237;
    letters to, 29, 185

  ---- ---- ----, Gustave, 20, 28, 116, 141;
    letters to, 83, 85, 91, 207, 267

  De la Rue, Warren:
    his lecture, 39;
    his eclipse photographs, 219

  Diamagnetic, A, 179

  ---- polarity, 192, 210

  Diamagnetism, Discovery of, 186

  Dielectric medium, 153, 159, 163

  Diploma-book, 271

  Discharge, electric, Forms of, 137, 162

  ---- ----, Dark, 162

  Discoveries, Value of, 63, 224, 248

  Displacement currents, 166

  Doctrine of conservation of energy, 167, 219

  ---- of correlation of forces, 172, 269, 270

  ---- of electrons, 148

  Domestic affairs, 49, 69, 244, 257

  Doubtful knowledge, Aversion for, 46, 92

  Dry rot in timber, 149

  Dumas:
    Reminiscences by, 20, 59, 240;
    and Arago’s copper, 106;
    discovery of oxalamide, 137


  E.

  Eddy-currents, Effects due to, 107, 191, 204

  Education, Views on, 278

  Eel, The electric, 167

  Electric light for lighthouses, 218, 269

  Electrical machine, Faraday’s own, 6

  ---- ----, The “new,” 121

  Electrochemical laws, 141, 147

  Electrodes, 143

  Electrolysis, 143

  Electrolytes, 143

  Electromagnetic rotations discovered, 51, 83, 87

  Electromagnetism, Foundations of, 77

  Electrons, Doctrine of, 148

  Electrotonic state, 116, 126, 166, 215

  Elocution, Lessons in, 43, 230

  Enthusiasm, 15, 89, 225, 240

  Ether, The (_see_ ÆTHER)

  Evolution of electricity from magnetism, 108, 114

  Examinations in chemistry, 277

  Experiment, Love of, 117, 230, 276

  ---- the touchstone of hypothesis, 221

  ---- _versus_ mathematics, 117, 239, 280

  Experimental researches in electricity and magnetism:
    the first series, 113;
    the last series, 216;
    Clerk Maxwell on, 218

  Expert work, 51, 61, 63, 274

  Explosions in the laboratory, 94


  F.

  Faraday, James, 1, 2, 224

  Faraday, Michael:
    born, 1;
    schooling of, 2;
    goes as errand boy, 3;
    apprenticed as bookbinder and stationer, 5;
    journeyman bookbinder, 9;
    attends Tatum’s lectures, 6;
    attends Sir H. Davy’s lectures, 8;
    acts as Davy’s amanuensis, 10;
    engaged at Royal Institution, 12;
    his foreign tour with Davy, 16;
    visits Paris, 18;
    visits Florence, 21;
    visits Geneva, 22, 28;
    returns to Royal Institution, 34;
    lectures at City Philosophical Society, 40, 43;
    loyalty to Davy, 42, 59, 269;
    begins original work, 46;
    falls in love, 46;
    his poem to Miss Barnard, 46;
    his wedding, 49;
    made superintendent of laboratory, 49, 98;
    discovers electromagnetic rotations, 51;
    elected F.R.S., 59;
    made D.C.L. of Oxford, 65;
    awarded Copley Medal, 69;
    declines professorship in London University, 66;
    receives a pension in Civil List, 72;
    appointed adviser to Trinity House, 67;
    appointed elder in Sandemanian church, 293;
    discovers magneto-electric induction, 112, 115;
    discovers magneto-optic rotation, 176;
    discovers diamagnetism, 186;
    readmitted to Sandemanian church, 297;
    exposes spiritualistic phenomena, 250;
    declines Presidency of Royal Society, 255;
    declines presidency of Royal Institution, 255;
    resigns professorship at Royal Institution, 259;
    resigns advisership to Trinity House, 259;
    resigns eldership in Sandemanian church, 259;
    decease and funeral, 260

  ----, Robert, 1, 2, 6, 249, 250

  ----, Sarah (Mrs. Faraday), 49, 50, 51, 223, 225, 255, 257, 291;
    letters to, 47, 48, 52, 53, 256

  Faraday’s father, 1, 2, 224, 289

  ---- mother, 1, 2, 12, 17, 22, 33, 41, 69, 289

  Fatalism, 52, 288

  Fees for professional work, 51, 61, 244, 274

  Field, The magnetic; first use of this term, 188

  Fishes, electrical, Researches on, 20, 139, 167

  Fluids, Alleged electric and magnetic, 212, 216, 218

  Foreign travel, 16, 17, 74, 224

  Fox, Caroline, Reminiscences of, 235

  _Fraser’s Magazine_ and Faraday’s pension, 72

  Fresnel’s announcement, 105

  Friday evenings at the Royal Institution, 33, 60, 100, 101, 149, 166,
        170, 192, 203, 219, 220, 225, 232, 236, 259

  Fuller, John, founds the Fullerian professorships, 36

  Funeral, 260


  G.

  Gases, Liquefaction of, 55, 91, 171

  ----, Magnetic properties of, 204, 208

  Gassiot, J. P., Reminiscences by, 13

  German language, Views on the, 280

  Gladstone, Dr. J. Hall, 69, 290

  Glass, Researches on, 95

  Glassites (_see_ SANDEMANIANS)

  Gold, Optical properties of, 219

  Gravity in relation to electricity, 204, 220, 285

  ----, Speculations as to, 195, 203

  Grove, Sir Wm., 263, 269

  Gymnotus, 167


  H.

  Hachette, Letter to, 266

  Hampton Court, House at, 257, 258

  Hare, R., Letter to, 269

  Harris, Sir W. Snow, 64, 269

  Heat, Effect of, on magnetism, 208

  Heavy-glass, 100, 176

  Helmholtz, Prof. H. von, 282, 283

  Henry, Professor Joseph, Reminiscence by, 241

  Herschel, Sir John, 57, 95, 107, 116, 131, 262, 297

  Home life, 49, 69, 223, 244, 257

  Honours awarded to Faraday, 69, 199, 244, 255, 271

  ----, scientific, Views on, 271

  Hypotheses, Free use of, 221, 241


  I.

  Ice a non-conductor, 140

  ----, Regelation of, 219

  Identity of electricity from different sources, 137

  Imagination, Use of the, 160, 227, 276

  Incandescent electric lamps, 199

  Income, 68, 245

  Indignation against wrong, 227

  Induced currents, 114

  Induction (electromagnetic), Discovery of, 114

  ---- (electrostatic), or influence, 153

  ----, Meaning of the term, 119

  Inductive capacity, 159

  Influence (_see_ INDUCTION)

  Inner conflicts, 226, 290

  Iodine, Davy’s experiments on, 19, 24, 27

  Ions, Origin of term, 144, 145


  J.

  Jenkin, Wm., observes spark at break, 150, 243

  Jones (_see_ BENCE JONES)

  Journals of foreign travel, 18, 224

  Juvenile lectures at Royal Institution, 33, 37, 61, 101, 233, 234,
        235, 258


  K.

  Keble, Rev. J., and the hodge-podge of philosophers, 65

  Kelvin, Lord:
    theory of electromotive forces, 148;
    on theory of magnetic permeability in æolotropic media, 201;
    on Faraday’s views of electricity, 284;
    letter from, 285

  Kerr, Dr. John:
    electro-optic discovery, 173;
    magneto-optic discovery, 182

  Kindliness, 226

  Knighthood no honour, 273

  Kundt, Aug., magneto-optic discovery, 182


  L.

  Laboratories at Albemarle Street, 36, 51, 66, 80, 84, 96

  Lateral effects of current, 151, 165, 170

  Lectures at Royal Institution:
    Davy’s, 8, 36;
    Faraday’s first, 227;
    Juvenile, 33, 37, 61, 101, 233, 234, 235, 258;
    afternoon, 37, 166

  ----, Friday night discourses, 33, 60, 100, 101, 149, 166, 170, 192,
        203, 219, 220, 225, 232, 236, 259

  Lectures at the London Institution, 101

  ---- at the British Association, 264

  ---- at St. George’s Hospital, 166

  ---- at Woolwich, 66, 101

  Lecturing, Views about, 16, 226, 232, 238

  Letters from Faraday to:
    Abbott, B., 7, 9, 15, 22, 25, 26, 41, 44, 228;
    Andrews, T., 273;
    Barnard, Miss Sarah, 47, 48;
    Becker, Dr., 244;
    Burdett-Coutts, Baroness, 240;
    Davy, Sir H., 10;
    De la Rive, A., 29, 185;
    De la Rive, G., 83, 85, 91, 207, 267;
    Deacon, Mrs., 253;
    Faraday, Mrs., 52, 53, 256;
    Grove, Sir Wm., 263;
    Hare, R., 269;
    Lovelace, Lady, 291;
    Matteucci, Prof. C., 253, 262, 267;
    Melbourne, Lord, 71;
    Moore, Miss, 207;
    Murray, Mr. John, 234;
    Paris, Dr. J. A., 10, 93;
    Percy, Dr. J., 253;
    Phillips, R., 61, 109, 114, 194, 270, 277;
    Riebau, G., 30;
    Royet, Dr. P., 99;
    Schönbein, Professor, 206, 252;
    the Deputy-Master of Trinity House, 67;
    Tyndall, Prof. J., 210, 264, 268, 277, 278, 280;
    Whewell, Rev. W., 145;
    Young, Dr. T., 97

  ---- to Faraday:
    From Sir H. Davy, 44, 45;
    from Baron Liebig, 225;
    from Sir W. Thomson (Lord Kelvin), 285;
    from Rev. W. Whewell, 116, 144, 145, 163, 205

  Liebig, J. von, Reminiscences by, 224, 282

  Light, Action of magnetism on, 176

  ----, Electromagnetic theory of, 197, 199, 213

  Lighthouses, Scientific work for, 67, 199, 218, 259

  Lines of force, 113, 133, 195, 208, 211, 213, 285;
    vibrations of, 195

  Liquefaction of gases, 55, 91, 171

  London University (_see_ UNIVERSITY)

  Love of children, 233, 235

  ----, Poetical diatribe against, and recantation, 40, 47

  Lovelace, Lady, Letter to, 291

  Love-letters of Faraday, 47, 48, 52, 58, 256


  M.

  Magnecrystallic forces, 201

  Magnetic lines, 113, 133, 195, 213, 214

  Magnetisation by light, 183

  ---- of light, 176

  Magnetism and cold, 167

  ---- of gases, 204

  ---- of rotation, Alleged, 106, 121

  Magneto-electric discovery, 95, 112

  ---- induction, 115

  ---- light, 120, 130, 218, 259

  ---- machines, 122, 125, 126, 218, 259

  Magneto-optical researches, 176, 182, 220

  Magrath, E., 7, 14, 60, 231

  Marcet, Mrs., Conversations on Chemistry, 6

  Masquerier teaches Faraday to draw, 8

  Mathematics _versus_ experiment, 117, 239, 280

  ----, Faraday’s views on, 280, 281

  ---- and Faraday’s methods, 217, 282

  Matteucci, C., Letters to, 253, 262, 267

  Maxwell (_see_ CLERK MAXWELL)

  Mayo, Herbert, Impromptu by, 117

  Meat-canning processes, 243

  Medium, Action in a, 157, 213, 216

  ----, The part played by the, 128, 153, 158, 194, 213

  Melbourne, Lord, and Faraday’s pension, 69

  Memory, Troubles of a defective, 7, 63, 74, 253

  Mental education, Views on, 278, 292

  Models, Use of, 104, 239

  Moigno, Abbé, Reminiscence by, 297

  Moll, G.:
    his electromagnets, 120;
    pamphlet on “Decline of Science,” 110, 262

  Moore, Miss, Letter to, 207

  Morichini’s experiments on magnetisation by light, 21, 183

  Murchison, Sir R., Reminiscence by, 227

  Music, Enjoyment of, 246


  N.

  Natural theology, Views on, 298

  New electrical machine, 121

  Newman, Rev. J. H., and the British Association, 65

  Newton, Mr. Jos., Reminiscence by, 254

  Nobili and Antinori, their mistake, 266

  Non-inductive winding, 150

  Notebooks a better test than examinations, 277

  ----, Faraday’s own, 8, 50, 73, 87, 90, 91, 108, 111, 118, 129, 141,
        143, 150, 153, 156, 167, 177, 180, 181, 182, 220


  O.

  Oersted’s discovery of electromagnetism, 77, 78

  Optical glass, Research on, 95, 100

  ---- illusions, Research on, 136

  ---- relations of electricity, 91, 149, 155, 167, 172, 174, 175

  ---- ---- of magnetism, 176, 182, 220

  Order and method, 68, 99, 200

  Owen, Lady, Reminiscences by, 236

  Oxford and the philosophers, 64

  Oxygen, Magnetic properties of, 208


  P.

  Paris, Dr. J. A., Letters to, 10, 93

  Passive state of iron, 167

  Peel, Sir Robert, 69, 70, 246

  Pension:
    declined, 71;
    accepted, 72

  Percy, Dr. John, Letter to, 253

  Permeability, Magnetic, in crystals, 201

  ---- ----, Research on, 206

  Personal appearance, 4, 18, 74, 255

  Phillips, Richard, 7, 44, 52, 54, 57, 59, 61, 84, 87, 193;
    letters to, 61, 109, 114, 194, 270, 277

  Phosphorescence, Lectures on, 136, 219

  Plücker, Julius:
    on magneto-optic action, 203;
    shows electric discharge, 240

  Poetry by Faraday, 40, 47

  Poisson:
    on Arago’s rotations, 107;
    on magnetic theory, 201

  Polar forces in crystals, 94, 200, 202

  Polemics in science hateful, 268

  Poles are only doors, 141, 241

  Politics, Indifference to, 19, 21, 33, 268

  Pollock, Lady, Reminiscences by, 235, 254, 257

  Practical applications of science, 63, 216, 224, 248, 259

  Preaching, Style of, 293

  Preservation of Raphael’s cartoons, 246

  Prince Consort, H.R.H. the, 237, 257, 278

  Principle of all dynamo machines, 216

  Priority in discovery, 265

  Professional work for fees, 51, 61, 274

  ---- ---- relinquished, 61, 274, 275

  Professorship of Chemistry at University College, The, 66, 277;
    declined, 66

  Professorships at the Royal Institution, 36

  Proportional judgment advocated, 242

  Public Schools Commission, Evidence given before, 278

  _Punch_, Caricature in, 252

  Pusey and science, 65


  Q.

  _Quarterly Journal of Science_, 39, 46, 75, 76, 82, 88, 92, 94, 104

  Queen Victoria, 257, 297


  R.

  Radiant matter, 40

  Rain torpedo, The, 20

  Ray-vibrations, Thoughts on, 193

  Regelation of ice, 219

  Reid, Miss, Reminiscences by, 223, 231

  Religious belief, 51, 289, 291

  Religious character, 71, 244, 245

  Remuneration of science, 44, 68, 244, 274

  Repulsions, magnetic, New, 190

  Research, Royal Institution as place for, 37

  ---- unhampered by other duties, 37

  Researches, Original:
    the four degrees of, 241;
    Faraday’s first, 76;
    Faraday’s last, 220;
    division into periods, 75;
    summary of, 216

  Residences:
    Weymouth Street, 2;
    Royal Institution, 13, 68;
    Hampton Court Cottage, 258

  Retardation of discharge, 161

  Riebau, George:
    Faraday’s employer, 3, 7, 22;
    Faraday apprenticed to, 51;
    letters and messages to, 29, 34

  Ring, The famous experiment with the, 108

  Robinson, H. Crabb, Reminiscences by, 8, 236

  Röntgen on displacement currents, 166

  Rotation of plane of polarisation of light, 177

  Rotations, electromagnetic, Discovery of, 51, 83, 87

  Royal Institution:
    foundation of, 35;
    Davy’s lectures at, 8, 36, 39;
    precarious state of, 22, 29, 35, 36, 68;
    laboratories of, 36;
    lectures at the, 37, 166;
    Christmas lectures, 33, 37, 61, 101, 233, 234, 235, 258;
    Friday night meetings, 33, 60, 100, 101, 149, 166, 170, 192, 203,
        219, 220, 225, 232, 236, 259;
    Presidency offered and declined, 255

  Royal Society:
    first papers read to the, 52, 263;
    candidature for Fellowship in the, 56, 57, 59;
    Faraday’s election as Fellow of the, 59;
    committee on optical glass, 95, 99;
    Member of Council, 136, 261;
    Presidency offered to him, 255, 263;
    dissatisfaction with, 262

  Ruhmkorff’s induction-coil, 219, 225

  Rumford, Benjamin Count of:
    founds the Royal Institution, 35;
    Faraday dines with, 34


  S.

  Sacrifice for Science, 63, 64, 234, 244

  Safety-lamp:
    Faraday aids Davy to invent the, 42;
    controversy about, 269

  Salaries paid to scientific men, 44, 68, 244, 274

  Sandemanians, 4, 51, 286

  Schönbein, Prof., Letters to, 206, 252

  Science in education, 279

  ---- teaching, Views on, 278

  Scientific societies, 261

  Scoffern, Dr., Anecdote by, 280

  Self-induction investigated, 150, 151

  Sermons, Faraday’s, 293

  Shaftesbury, Earl of, 69

  Sirium, _alias_ Vestium, 46, 77

  Sisters, His letters to his, 32

  Smart, B. H., teaches elocution, 43, 230

  Snow-Harris (_see_ HARRIS)

  Social character, 245

  Society of Arts, 14

  Source of electromotive force in cell, 168

  South, Sir James, 6, 57, 69, 70, 97, 262

  Spark from a magnet, 64, 119, 130

  Specific inductive capacity, 159

  Spiritualists, Opinion of, 251

  Steel, Research on, 82

  Stinginess of British Government towards science, 274

  Sturgeon, W.:
    his invention of the electromagnet, 102, 226;
    on Arago’s rotations, 107

  Submarine cables, 161

  Sunday observance, 24, 51, 55, 224, 295, 297


  T.

  Table-turning explained, 251

  Tatum’s lectures, 6, 14

  Testimonials of candidates, Repugnance to, 277

  Thames impurities, 252

  Thomson, Sir W. (_see_ KELVIN)

  Thoughts on ray-vibrations, 193

  Thunderstorms enjoyed, 240

  Time of propagation of magnetism, 220, 284

  Toronto, what its university might have been, 277, 278

  Torpedo, The, 20

  Trinity House, Scientific adviser to, 67, 199, 218, 259

  Tubes of force, 211

  Turner, J. W. M., R.A., Advice to, about pigments, 246

  Tyndall, Prof.:
    reminiscences by, 4, 49, 74, 175, 187, 225, 255, 290, 296, 299;
    his “Faraday as a Discoverer,” 4, 130, 157, 169, 202;
    letters to, 210, 264, 268, 277, 278, 280


  U.

  Utility of discoveries, 63, 224, 248

  University College, Professorship in, 66, 277

  University of London:
    Senator of, 275;
    degrees in science, 275


  V.

  Varley, Cornelius, 5, 294

  Velocipede riding, 74

  Vesuvius, Ascents of, 22, 33

  Vibrations, Thoughts on ray-, 193

  Visits to the sick, 245, 296

  Volta, Count Alessandro, Meeting with, 22

  Volta-electric induction, 115

  Voltameter, 146


  W.

  Water, On freezing of, 203

  Wellington, The Duke of, on practical application of discovery, 248

  Wheatstone, Sir Charles:
    on velocity of discharge, 149, 161;
    his electric chronoscope, 192

  Whewell, Rev. W., Correspondence with, about terms, 116, 144, 145,
        163, 205

  White, Walter, Reminiscences by, 253, 263

  William IV., King, 72, 73

  Wiseman, Cardinal, Meeting with, 297

  Wollaston, Dr. W. H., Misunderstanding with, 51, 56, 57, 58, 84, 89

  Woolwich Academy lectures, 66, 101

  Working, Method of, 66, 242, 247


  Y.

  Young, Dr. T., Letter from, 97


  Z.

  Zeeman’s magneto-optic discovery, 220



PRINTED BY CASSELL & COMPANY, LIMITED, LA BELLE SAUVAGE, LONDON, E.C.




Transcriber’s Notes


Punctuation, some hyphenation, and spelling were made consistent when a
predominant preference was found in the original book; otherwise they
were not changed. The original book inconsistently followed “electro”
with a hyphen, and that has not been changed here.

Simple typographical errors were corrected; unbalanced quotation
marks were remedied when the change was obvious, and otherwise left
unbalanced.

Illustrations in this eBook have been positioned between paragraphs
and outside quotations. In versions of this eBook that support
hyperlinks, the page references in the List of Illustrations lead to
the corresponding illustrations.

Running page headers in the original book are shown here as sidenotes,
placed between paragraphs and near the topics to which they refer.

Footnotes, originally at the bottoms of pages, have been renumbered
into a single sequence, collected, and moved to just above the Index.

The index was reformatted slightly and was not checked systematically
for proper alphabetization or correct page references.