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  THE
  MARTYRS OF SCIENCE,
  OR
  THE LIVES
  OF
  GALILEO, TYCHO BRAHE, AND KEPLER.

  BY

  SIR DAVID BREWSTER, K.H. D.C.L.,
  PRINCIPAL OF THE UNITED COLLEGE OF ST SALVATOR AND ST LEONARD,
  ST ANDREWS; FELLOW OF THE ROYAL SOCIETY OF LONDON; VICE-PRESIDENT
  OF THE ROYAL SOCIETY OF EDINBURGH; CORRESPONDING MEMBER
  OF THE INSTITUTE OF FRANCE; AND MEMBER OF THE
  ACADEMIES OF ST PETERSBURG, STOCKHOLM,
  BERLIN, COPENHAGEN, GOTTINGEN,
  PHILADELPHIA, &c. &c.

  LONDON:
  JOHN MURRAY, ALBEMARLE STREET.
  1841.

  G. S. TULLIS, PRINTER, CUPAR.




  TO THE
  RIGHT HON. FRANCIS LORD GRAY,
  F.R.S., F.R.S.E.

MY LORD,

In submitting this volume to the public under your Lordship's auspices,
I avail myself of the opportunity thus afforded me of expressing the
deep sense which I entertain of the friendship and kindness with which
your Lordship has so long honoured me.

Although in these days, when Science constitutes the power and wealth of
nations, and encircles the domestic hearth with its most substantial
comforts, there is no risk of its votaries being either persecuted or
neglected, yet the countenance of those to whom Providence has given
rank and station will ever be one of the most powerful incitements to
scientific enterprise, as well as one of its most legitimate rewards.
Next to the satisfaction of cultivating Science, and thus laying up the
only earthly treasure which we can carry along with us into a better
state, is that of having encouraged and assisted others in the same
beneficent labours. That your Lordship may long continue to enjoy these
sources of happiness is the earnest prayer of,

MY LORD,

Your Lordship's

Most faithful and obedient servant,

DAVID BREWSTER.

ST LEONARDS, ST ANDREWS,

October 12, 1840.




CONTENTS.


LIFE OF GALILEO.

                                                                   Page.
CHAPTER I.                                                             1

  Peculiar interest attached to his Life--His Birth--His early
  studies--His passion for Mathematics--His work on the Hydrostatic
  Balance--Appointed Lecturer on Mathematics at Pisa--His antipathy
  to the Philosophy of Aristotle--His contentions with the
  Aristotelians--Chosen Professor of Mathematics in Padua--Adopts the
  Copernican system, but still teaches the Ptolemaic doctrine--His
  alarming illness--He observes the new Star in 1604--His Magnetical
  experiments,

CHAPTER II.                                                           20

  Cosmo, Grand Duke of Tuscany, invites Galileo to Pisa--Galileo
  visits Venice in 1609, where he first hears of the Telescope--He
  invents and constructs one, which excites a great
  sensation--Discovers Mountains in the Moon, and Forty Stars in the
  Pleiades--Discovers Jupiter's Satellites in 1610--Effect of this
  discovery on Kepler--Manner in which these discoveries were
  received--Galileo appointed Mathematician to Cosmo--Mayer claims the
  discovery of the Satellites of Jupiter--Harriot observes them in
  England in October 1610,

CHAPTER III.                                                          42

  Galileo announces his discoveries in Enigmas--Discovers the
  Crescent of Venus--the Ring of Saturn--the Spots on the
  Sun--Similar Observations made in England by Harriot--Claims of
  Fabricius and Scheiner to the discovery of the Solar
  Spots--Galileo's Letters to Velser on the claims of Scheiner--His
  residence at the Villa of Salviati--Composes his work on Floating
  Bodies, which involves him in new controversies,

CHAPTER IV.                                                           56

  Galileo treats his Opponents with severity and sarcasm--He is aided
  by the Sceptics of the day--The Church Party the most
  powerful--Galileo commences the attack, and is answered by Caccini,
  a Dominican--Galileo's Letter to the Grand Duchess of Tuscany, in
  support of the motion of the Earth and the stability of the
  Sun--Galileo visits Rome--Is summoned before the Inquisition--And
  renounces his opinions as Heretical--The Inquisition denounces the
  Copernican system--Galileo has an audience of the Pope, but still
  maintains his opinions in private society--Proposes to find out the
  Longitude at Sea by means of Jupiter's Satellites--His negotiation
  on this subject with the Court of Spain--Its failure--He is unable
  to observe the three Comets of 1618, but is involved in the
  controversy to which they gave rise,

CHAPTER V.                                                            72

  Urban VIII., Galileo's friend, raised to the Pontificate--Galileo
  goes to Rome to offer his congratulations--The Pope loads Galileo
  with presents, and promises a Pension to his Son--Galileo in
  pecuniary difficulties, owing to the death of his patron,
  Cosmo--Galileo again rashly attacks the Church, notwithstanding the
  Pope's kindness--He composes his System of the World, to
  demonstrate the Copernican System--Artfully obtains a license to
  print it--Nature of the work--Its influence on the public mind--The
  Pope resolves on suppressing it--Galileo summoned before the
  Inquisition--His Trial--His Defence--His formal Abjuration of his
  Opinions--Observations on his conduct--The Pope shews great
  indulgence to Galileo, who is allowed to return to his own house at
  Arcetri as the place of his confinement,

CHAPTER VI.                                                          102

  Galileo loses his favourite Daughter--He falls into a state of
  melancholy and ill health--Is allowed to go to Florence for its
  recovery in 1638--But is prevented from leaving his House or
  receiving his Friends--His friend Castelli permitted to visit him
  in the presence of an Officer of the Inquisition--He composes his
  celebrated Dialogues on Local Motion--Discovers the Moon's
  Libration--Loses the sight of one Eye--The other Eye attacked by
  the same Disease--Is struck Blind--Negociates with the Dutch
  Government respecting his Method of finding the Longitude--He is
  allowed free intercourse with his Friends--His Illness and Death in
  1642--His Epitaph--His Social, Moral, and Scientific Character,

       *       *       *       *       *


LIFE OF TYCHO BRAHE.

CHAPTER I.                                                           123

  Tycho's Birth, Family, and Education--An Eclipse of the Sun turns
  his attention to Astronomy--Studies Law at Leipsic--But pursues
  Astronomy by stealth--His Uncle's Death--He returns to Copenhagen,
  and resumes his Observations--Revisits Germany--Fights a Duel, and
  loses his Nose--Visits Augsburg, and meets Hainzel--Who assists him
  in making a large Quadrant--Revisits Denmark--And is warmly
  received by the King--He settles at his Uncle's Castle of
  Herritzvold--His Observatory and Laboratory--Discovers the new Star
  in Cassiopeia--Account of this remarkable Body--Tycho's Marriage
  with a Peasant Girl--Which irritates his Friends--His Lectures on
  Astronomy--He visits the Prince of Hesse--Attends the Coronation of
  the Emperor Rudolph at Ratisbon--He returns to Denmark,

CHAPTER II.                                                          145

  Frederick II. patronizes Tycho--And resolves to establish him in
  Denmark--Grants him the Island of Huen for Life--And Builds the
  splendid Observatory of Uraniburg--Description of the Island, and
  of the Observatory--Account of its Astronomical Instruments--Tycho
  begins his Observations--His Pupils--Tycho is made Canon of
  Rothschild, and receives a large Pension--His Hospitality to his
  Visitors--Ingratitude of Wittichius--Tycho sends an Assistant to
  take the Latitude of Frauenburg and Konigsberg--Is visited by
  Ulric, Duke of Mecklenburg--Change in Tycho's fortunes,

CHAPTER III.                                                         160

  Tycho's Labours do honour to his Country--Death of Frederick
  II.--James VI. of Scotland visits Tycho at Uraniburg--Christian IV.
  visits Tycho--The Duke of Brunswick's visit to Tycho--The Danish
  Nobility, jealous of his fame, conspire against him--He is
  compelled to quit Uraniburg--And to abandon his Studies--Cruelty of
  the Minister Walchendorp--Tycho quits Denmark with his Family and
  Instruments--Is hospitably received by Count Rantzau--Who
  introduces him to the Emperor Rudolph--The Emperor invites him to
  Prague--He gives him a Pension of 3000 Crowns--And the Castle of
  Benach as a Residence and an Observatory--Kepler visits Tycho--Who
  obtains for him the Appointment of Mathematician to Rudolph,

CHAPTER IV.                                                          179

  Tycho resumes his Astronomical Observations--Is attacked with a
  Painful Disease--His Sufferings and Death in 1601--His Funeral--His
  Temper--His Turn for Satire and Raillery--His Piety--Account of his
  Astronomical Discoveries--His Love of Astrology and
  Alchymy--Observations on the Character of the Alchymists--Tycho's
  Elixir--His Fondness for the Marvellous--His Automata and Invisible
  Bells--Account of the Idiot, called Lep, whom he kept as a
  Prophet--History of Tycho's Instruments--His Great Brass Globe
  preserved at Copenhagen--Present state of the Island of Huen,

       *       *       *       *       *


LIFE OF JOHN KEPLER.

CHAPTER I.                                                           203

  Kepler's Birth in 1571--His Family--And early Education--The
  Distresses and Poverty of his Family--He enters the Monastic School
  of Maulbronn--And is admitted into the University of Tubingen,
  where he distinguishes himself, and takes his Degree--He is
  appointed Professor of Astronomy and Greek in 1594--His first
  speculations on the Orbits of the Planets--Account of their
  Progress and Failure--His "Cosmographical Mystery" published--He
  Marries a Widow in 1597--Religious troubles at Gratz--He retires
  from thence to Hungary--Visits Tycho at Prague in 1600--Returns to
  Gratz, which he again quits for Prague--He is taken ill on the
  road--Is appointed Tycho's Assistant in 1601--Succeeds Tycho as
  Imperial Mathematician--His Work on the New Star of 1604--Singular
  specimen of it,

CHAPTER II.                                                          220

  Kepler's Pecuniary Embarrassments--His Inquiries respecting the Law
  of Refraction--His Supplement to Vitellio--His Researches on
  Vision--His Treatise on Dioptrics--His Commentaries on Mars--He
  discovers that the orbit of Mars is an Ellipse, with the Sun in one
  focus--And extends this discovery to all the other Planets--He
  establishes the two first laws of Physical Astronomy--His Family
  Distresses--Death of his Wife--He is appointed Professor of
  Mathematics at Linz--His Method of Choosing a Second Wife--Her
  Character, as given by Himself--Origin of his Treatise on
  Gauging--He goes to Ratisbon to give his Opinion to the Diet on the
  change of Style--He refuses the Mathematical Chair at Bologna,

CHAPTER III.                                                         237

  Kepler's continued Embarrassments--Death of Mathias--Liberality of
  Ferdinand--Kepler's "Harmonies of the World"--The Epitome of the
  Copernican Astronomy--It is prohibited by the Inquisition--Sir
  Henry Wotton, the British Ambassador, invites Kepler to
  England--He declines the Invitation--Neglect of Genius by the
  English Government--Trial of Kepler's Mother--Her final
  Acquittal--And Death at the age of Seventy-five--The States of
  Styria burn publicly Kepler's Calendar--He receives his Arrears of
  Salary from Ferdinand--The Rudolphine Tables published in 1628--He
  receives a Gold Chain from the Grand Duke of Tuscany--He is
  Patronised by the Duke of Friedland--He removes to Sagan, in
  Silesia--Is appointed Professor of Mathematics at Rostoch--Goes to
  Ratisbon to receive his Arrears--His Death, Funeral, and
  Epitaph--Monument Erected to his Memory in 1803--His Family--His
  Posthumous Volume, entitled "The Dream, or Lunar Astronomy,"

CHAPTER IV.                                                          252

  Number of Kepler's published Works--His numerous Manuscripts in 22
  folio volumes--Purchased by Hevelius, and afterwards by Hansch--Who
  publishes Kepler's Life and Correspondence at the expense of
  Charles VI.--The History of the rest of his Manuscripts, which are
  deposited in the Library of the Academy of Sciences at St
  Petersburg--General Character of Kepler--His Candour in
  acknowledging his Errors--His Moral and Religious Character--His
  Astrological Writings and Opinions considered--His Character as an
  Astronomer and a Philosopher--The Splendour of his
  Discoveries--Account of his Method of Investigating Truth,




LIFE OF GALILEO.




CHAPTER I.

     _Peculiar interest attached to his Life--His Birth--His early
     studies--His passion for Mathematics--His work on the Hydrostatic
     Balance--Appointed Lecturer on Mathematics at Pisa--His antipathy
     to the Philosophy of Aristotle--His contentions with the
     Aristotelians--Chosen professor of Mathematics in Padua--Adopts the
     Copernican system, but still teaches the Ptolemaic doctrine--His
     alarming illness--He observes the new Star in 1604--His magnetical
     experiments._


The history of the life and labours of Galileo is pregnant with a
peculiar interest to the general reader, as well as to the philosopher.
His brilliant discoveries, the man of science regards as his peculiar
property; the means by which they were made, and the development of his
intellectual character, belong to the logician and to the philosopher;
but the triumphs and the reverses of his eventful life must be claimed
for our common nature, as a source of more than ordinary instruction.

The lengthened career which Providence assigned to Galileo was filled up
throughout its rugged outline with events even of dramatic interest. But
though it was emblazoned with achievements of transcendent magnitude,
yet his noblest discoveries were the derision of his contemporaries, and
were even denounced as crimes which merited the vengeance of Heaven.
Though he was the idol of his friends, and the favoured companion of
princes, yet he afterwards became the victim of persecution, and spent
some of his last hours within the walls of a prison; and though the
Almighty granted him, as it were, a new sight to descry unknown worlds
in the obscurity of space, yet the eyes which were allowed to witness
such wonders, were themselves doomed to be closed in darkness.

Such were the lights and shadows in which history delineates

    "The starry Galileo with his woes."[1]

      [1] Childe Harold, canto iv. stanza liv.


But, however powerful be their contrasts, they are not unusual in
their proportions. The balance which has been struck between his days of
good and evil, is that which regulates the lot of man, whether we study
it in the despotic sway of the autocrat, in the peaceful inquiries of
the philosopher, or in the humbler toils of ordinary life.

Galileo Galilei was born at Pisa, on the 15th of February, 1564, and was
the eldest of a family of three sons and three daughters. Under the name
of Bonajuti, his noble ancestors had filled high offices at Florence;
but about the middle of the 14th century they seem to have abandoned
this surname for that of Galileo. Vincenzo Galilei, our author's father,
was himself a philosopher of no mean powers; and though his talents seem
to have been exercised only in the composition of treatises on the
theory and practice of music, yet he appears to have anticipated even
his son in a just estimate of the philosophy of the age, and in a
distinct perception of the true method of investigating truth.[2]

     [2] Life of Galileo, Library of Useful Knowledge, p. 1.

The early years of Galileo were, like those of almost all great
experimental philosophers, spent in the construction of instruments and
pieces of machinery, which were calculated chiefly to amuse himself and
his schoolfellows. This employment of his hands, however, did not
interfere with his regular studies; and though, from the straitened
circumstances of his father, he was educated under considerable
disadvantages, yet he acquired the elements of classical literature, and
was initiated into all the learning of the times. Music, drawing, and
painting were the occupations of his leisure hours; and such was his
proficiency in these arts, that he was reckoned a skilful performer on
several musical instruments, especially the lute; and his knowledge of
pictures was held in great esteem by some of the best artists of his
day.

Galileo seems to have been desirous of following the profession of a
painter: but his father had observed decided indications of early
genius; and, though by no means able to afford it, he resolved to send
him to the university to pursue the study of medicine. He accordingly
enrolled himself as a scholar in arts at the university of Pisa, on the
5th of November, 1581, and pursued his medical studies under the
celebrated botanist Andrew Cæsalpinus, who filled the chair of medicine
from 1567 to 1592.

In order to study the principles of music and drawing, Galileo found it
necessary to acquire some knowledge of geometry. His father seems to
have foreseen the consequences of following this new pursuit, and though
he did not prohibit him from reading Euclid under Ostilio Ricci, one of
the professors at Pisa, yet he watched his progress with the utmost
jealousy, and had resolved that it should not interfere with his medical
studies. The demonstrations, however, of the Greek mathematician had too
many charms for the ardent mind of Galileo. His whole attention was
engrossed with the new truths which burst upon his understanding; and
after many fruitless attempts to check his ardour and direct his
thoughts to professional objects, his father was obliged to surrender
his parental control, and allow the fullest scope to the genius of his
son.

From the elementary works of geometry, Galileo passed to the writings of
Archimedes; and while he was studying the hydrostatical treatise[3] of
the Syracusan philosopher, he wrote his essay on the hydrostatical
balance,[4] in which he describes the construction of the instrument,
and the method by which Archimedes detected the fraud committed by the
jeweller in the composition of Hiero's crown. This work gained for its
author the esteem of Guido Ubaldi, who had distinguished himself by his
mechanical and mathematical acquirements, and who engaged his young
friend to investigate the subject of the centre of gravity in solid
bodies. The treatise on this subject, which Galileo presented to his
patron, proved the source of his future success in life.

     [3] De Insidentibus in Fluido.

     [4] Opere di Galileo. Milano, 1810, vol. iv. p. 248-257.

Through the Cardinal del Monte, the brother-in-law of Ubaldi, the
reigning Duke of Tuscany, Ferdinand de Medici was made acquainted with
the merits of our young philosopher; and, in 1589, he was appointed
lecturer on mathematics at Pisa. As the salary, however, attached to
this office was only sixty crowns, he was compelled to enlarge this
inadequate income by the additional occupation of private teaching, and
thus to encroach upon the leisure which he was anxious to devote to
science.

With this moderate competency, Galileo commenced his philosophical
career. At the early age of eighteen, when he had entered the
university, his innate antipathy to the Aristotelian philosophy began to
display itself. This feeling was strengthened by his earliest inquiries;
and upon his establishment at Pisa he seems to have regarded the
doctrines of Aristotle as the intellectual prey which, in his chace of
glory, he was destined to pursue. Nizzoli, who flourished near the
beginning of the sixteenth century, and Giordano Bruno, who was burned
at Rome in 1600, led the way in this daring pursuit; but it was reserved
for Galileo to track the Thracian boar through its native thickets, and,
at the risk of his own life, to strangle it in its den.

With the resolution of submitting every opinion to the test of
experiment, Galileo's first inquiries at Pisa were directed to the
mechanical doctrines of Aristotle. Their incorrectness and absurdity
soon became apparent; and with a zeal, perhaps, bordering on
indiscretion, he denounced them to his pupils with an ardour of manner
and of expression proportioned to his own conviction of the truth. The
detection of long-established errors is apt to inspire the young
philosopher with an exultation which reason condemns. The feeling of
triumph is apt to clothe itself in the language of asperity; and the
abettor of erroneous opinions is treated as a species of enemy to
science. Like the soldier who fleshes his first spear in battle, the
philosopher is apt to leave the stain of cruelty on his early
achievements. It is only from age and experience, indeed, that we can
expect the discretion of valour, whether it is called forth in
controversy or in battle. Galileo seems to have waged this stern warfare
against the followers of Aristotle; and such was the exasperation which
was excited by his reiterated and successful attacks, that he was
assailed, during the rest of his life, with a degree of rancour which
seldom originates in a mere difference of opinion. Forgetting that all
knowledge is progressive, and that the errors of one generation call
forth the comments, and are replaced by the discoveries, of the next,
Galileo did not anticipate that his own speculations and incompleted
labours might one day provoke unmitigated censure; and he therefore
failed in making allowance for the prejudices and ignorance of his
opponents. He who enjoys the proud lot of taking a position in advance
of his age, need not wonder that his less gifted contemporaries are left
behind. Men are not necessarily obstinate because they cleave to deeply
rooted and venerable errors, nor are they absolutely dull when they are
long in understanding and slow in embracing newly discovered truths.

It was one of the axioms of the Aristotelian mechanics, that the heavier
of two falling bodies would reach the ground sooner than the other, and
that their velocities would be proportional to their weights. Galileo
attacked the arguments by which this opinion was supported; and when he
found his reasoning ineffectual, he appealed to direct experiment. He
maintained, that all bodies would fall through the same height in the
same time, if they were not unequally retarded by the resistance of the
air: and though he performed the experiment with the most satisfactory
results, by letting heavy bodies fall from the leaning tower of Pisa,
yet the Aristotelians, who with their own eyes saw the unequal weights
strike the ground at the same instant, ascribed the effect to some
unknown cause, and preferred the decision of their master to that of
nature herself.

Galileo could not brook this opposition to his discoveries; nor could
the Aristotelians tolerate the rebukes of their young instructor. The
two parties were, consequently, marshalled in hostile array; when,
fortunately for both, an event occurred, which placed them beyond the
reach of danger. Don Giovanni de Medici, a natural son of Cosmo, had
proposed a method of clearing out the harbour of Leghorn. Galileo, whose
opinion was requested, gave such an unfavourable report upon it, that
the disappointed inventor directed against him all the force of his
malice. It was an easy task to concentrate the malignity of his enemies
at Pisa; and so effectually was this accomplished, that Galileo resolved
to accept another professorship, to which he had been previously
invited.

The chair of mathematics in the university of Padua having been vacant
for five years, the republic of Venice had resolved to fill it up; and,
on the recommendation of Guido Ubaldi, Galileo was appointed to it, in
1592, for a period of six years.

Previous to this event, Galileo had lost his father, who died, in 1591,
at an advanced age. As he was the eldest son, the support of the family
naturally devolved upon him; and this sacred obligation must have
increased his anxiety to better his circumstances, and therefore added
to his other inducements to quit Pisa. In September 1592, he removed to
Padua, where he had a salary of only 180 florins, and where he was again
obliged to add to his income by the labours of tuition. Notwithstanding
this fruitless occupation of his time, he appears to have found leisure
for composing several of his works, and completing various inventions,
which will be afterwards described. His manuscripts were circulated
privately among his friends and pupils; but some of them strayed beyond
this sacred limit, and found their way into the hands of persons, who
did not scruple to claim and publish, as their own, the discoveries and
inventions which they contained.

It is not easy to ascertain the exact time when Galileo became a convert
to the doctrines of Copernicus, or the particular circumstances under
which he was led to adopt them. It is stated by Gerard Voss, that a
public lecture of Moestlin, the instructor of Kepler, was the means of
making Galileo acquainted with the true system of the universe. This
assertion, however, is by no means probable; and it has been ably shown,
by the latest biographer of Galileo,[5] that, in his dialogues on the
Copernican system, our author gives the true account of his own
conversion. This passage is so interesting, that we shall give it
entire.

     [5] Life of Galileo, in Library of Useful Knowledge, p. 9.

"I cannot omit this opportunity of relating to you what happened to
myself at the time when this opinion (the Copernican system) began to be
discussed. I was then a very young man, and had scarcely finished my
course of philosophy, which other occupations obliged me to leave off,
when there arrived in this country, from Rostoch, a foreigner, whose
name, I believe, was Christian Vurstisius (Wurteisen), a follower of
Copernicus. This person delivered, on this subject, two or three
lectures in a certain academy, and to a crowded audience. Believing that
several were attracted more by the novelty of the subject than by any
other cause, and being firmly persuaded that this opinion was a piece of
solemn folly, I was unwilling to be present. Upon interrogating,
however, some of those who were there, I found that they all made it a
subject of merriment, with the exception of one, who assured me that it
was not a thing wholly ridiculous. As I considered this individual to be
both prudent and circumspect, I repented that I had not attended the
lectures; and, whenever I met any of the followers of Copernicus, I
began to inquire if they had always been of the same opinion. I found
that there was not one of them who did not declare that he had long
maintained the very opposite opinions, and had not gone over to the new
doctrines till he was driven by the force of argument. I next examined
them one by one, to see if they were masters of the arguments on the
opposite side; and such was the readiness of their answers, that I was
satisfied they had not taken up this opinion from ignorance or vanity.
On the other hand, whenever I interrogated the Peripatetics and the
Ptolemeans--and, out of curiosity, I have interrogated not a
few--respecting their perusal of Copernicus's work, I perceived that
there were few who had seen the book, and not one who understood it. Nor
have I omitted to inquire among the followers of the Peripatetic
doctrines, if any of them had ever stood on the opposite side; and the
result was, that there was not one. Considering, then, that nobody
followed the Copernican doctrine, who had not previously held the
contrary opinion, and who was not well acquainted with the arguments of
Aristotle and Ptolemy; while, on the other hand, nobody followed Ptolemy
and Aristotle, who had before adhered to Copernicus, and had gone over
from him into the camp of Aristotle;--weighing, I say, these things, I
began to believe that, if any one who rejects an opinion which he has
imbibed with his milk, and which has been embraced by an infinite
number, shall take up an opinion held only by a few, condemned by all
the schools, and really regarded as a great paradox, it cannot be
doubted that he must have been induced, not to say driven, to embrace it
by the most cogent arguments. On this account I have become very curious
to penetrate to the very bottom of the subject."[6]

     [6] Systema Cosmicum, Dial. ii. p. 121.

It appears, on the testimony of Galileo himself, that he taught the
Ptolemaic system, in compliance with the popular feeling, after he had
convinced himself of the truth of the Copernican doctrines. In the
treatise on the sphere, indeed, which bears his name,[7] and which must
have been written soon after he went to Padua, and subsequently to 1592,
the stability of the earth, and the motion of the sun, are supported by
the very arguments which Galileo afterwards ridiculed; but we have no
means of determining whether or not he had then adopted the true system
of the universe. Although he might have taught the Ptolemaic system in
his lectures after he had convinced himself of its falsehood, yet it is
not likely that he would go so far as to publish to the world, as true,
the very doctrines which he despised. In a letter to Kepler, dated in
1597, he distinctly states that he _had, many years ago, adopted the
opinions of Copernicus_; but that _he had not yet dared to publish his
arguments in favour of them, and his refutation of the opposite
opinions_. These facts would leave us to place Galileo's conversion
somewhere between 1593 and 1597, although _many_ years cannot be said
to have elapsed between these two dates.

     [7] The authenticity of this work has been doubted. It was printed
     at Rome, in 1656, from a MS. in the library of Somaschi, at Venice.
     See Opere di Galileo, tom. vii. p. 427.

At this early period of Galileo's life, in the year 1593, he met with an
accident which had nearly proved fatal. A party at Padua, of which he
was one, were enjoying, at an open window, a current of air, which was
artificially cooled by a fall of water. Galileo unfortunately fell
asleep under its influence; and so powerful was its effect upon his
robust constitution, that he contracted a severe chronic disorder,
accompanied with acute pains in his body, and loss of sleep and
appetite, which attacked him at intervals during the rest of his life.
Others of the party suffered still more severely, and perished by their
own rashness.

Galileo's reputation was now widely extended over Europe. The Archduke
Ferdinand (afterwards Emperor of Germany), the Landgrave of Hesse, and
the Princes of Alsace and Mantua, honoured his lectures with their
presence; and Prince Gustavus Adolphus of Sweden also received
instructions from him in mathematics, during his sojourn in Italy.

When Galileo had completed the first period of his engagement at Padua,
he was re-elected for other six years, with an increased salary of 320
florins. This liberal addition to his income is ascribed by Fabbroni to
the malice of one of his enemies, who informed the Senate that Galileo
was living in illicit intercourse with Marina Gamba. Without inquiring
into the truth of the accusation, the Senate is said to have replied,
that if "he had a family to support, he had the more need of an
increased salary." It is more likely that the liberality of the republic
had been called forth by the high reputation of their professor, and
that the terms of their reply were intended only to rebuke the malignity
of the informer. The mode of expression would seem to indicate that one
or more of Galileo's children had been born previous to his re-election
in 1598; but as this is scarcely consistent with other facts, we are
disposed to doubt the authenticity of Fabbroni's anecdote.

The new star which attracted the notice of astronomers in 1604, excited
the particular attention of Galileo. The observations which he made upon
it, and the speculations which they suggested, formed the subject of
three lectures, the beginning of the first of which only has reached
our times. From the absence of parallax, he proved that the common
hypothesis of its being a meteor was erroneous, and that, like the fixed
stars, it was situated far beyond the bounds of our own system. The
popularity of the subject attracted crowds to his lecture-room; and
Galileo had the boldness to reproach his hearers for taking so deep an
interest in a temporary phenomenon, while they overlooked the wonders of
creation which were daily presented to their view.

In the year 1606, Galileo was again appointed to the professorship at
Padua, with an augmented stipend of 520 florins. His popularity had now
risen so high, that his audience could not be accommodated in his
lecture-room; and even when he had assembled them in the school of
medicine, which contained 1000 persons, he was frequently obliged to
adjourn to the open air.

Among the variety of pursuits which occupied his attention, was the
examination of the properties of the loadstone. In 1607, he commenced
his experiments; but, with the exception of a method of arming
loadstones, which, according to the report of Sir Kenelm Digby, enabled
them to carry twice as much weight as before, he does not seem to have
made any additions to our knowledge of magnetism. He appears to have
studied with care the admirable work of our countryman, Dr Gilbert, "De
Magnete," which was published in 1600; and he recognised in the
experiments and reasonings of the English philosopher the principles of
that method of investigating truth which he had himself adopted. Gilbert
died in 1603, in the 63d year of his age, and probably never read the
fine compliment which was paid to him by the Italian philosopher--"I
extremely praise, admire, and envy this author."




CHAPTER II.

     _Cosmo, Grand Duke of Tuscany, invites Galileo to Pisa--Galileo
     visits Venice in 1609, where he first hears of the Telescope--He
     invents and constructs one, which excites a great
     sensation--Discovers Mountains in the Moon, and Forty Stars in the
     Pleiades--Discovers Jupiter's Satellites in 1610--Effect of this
     discovery on Kepler--Manner in which these discoveries were
     received--Galileo appointed Mathematician to Cosmo--Mayer claims
     the discovery of the Satellites of Jupiter--Harriot observes them
     in England in October 1610._


In the preceding chapter we have brought down the history of Galileo's
labours to that auspicious year in which he first directed the telescope
to the heavens. No sooner was that noble instrument placed in his hands,
than Providence released him from his professional toils, and supplied
him with the fullest leisure and the amplest means for pursuing and
completing the grandest discoveries.

Although he had quitted the service and the domains of his munificent
patron, the Grand Duke of Tuscany, yet he maintained his connection with
the family, by visiting Florence during his academic vacations, and
giving mathematical instruction to the younger branches of that
distinguished house. Cosmo, who had been one of his pupils, now
succeeded his father Ferdinand; and having his mind early imbued with a
love of knowledge, which had become hereditary in his family, he felt
that the residence of Galileo within his dominions, and still more his
introduction into his household, would do honour to their common
country, and reflect a lustre upon his own name. In the year 1609,
accordingly, Cosmo made proposals to Galileo to return to his original
situation at Pisa. These overtures were gratefully received; and in the
arrangements which Galileo on this occasion suggested, as well as in the
manner in which they were urged, we obtain some insight into his temper
and character. He informs the correspondent through whom Cosmo's offer
was conveyed, that his salary of 520 florins at Padua would be increased
to as many crowns at his re-election, and that he could enlarge his
income to any extent he pleased, by giving private lectures and
receiving pupils. His public duties, he stated, occupied him only sixty
half-hours in the year; but his studies suffered such interruptions from
his domestic pupils and private lectures, that his most ardent wish was
to be relieved from them, in order that he might have sufficient rest
and leisure, before the close of his life, to finish and publish those
great works which he had projected. In the event, therefore, of his
returning to Pisa, he hoped that it would be the first object of his
serene highness to give him leisure to complete his works without the
drudgery of lecturing. He expresses his anxiety to gain his bread by his
writings, and he promises to dedicate them to his serene master. He
enumerates, among these books, two on the system of the universe, three
on local motion, three books of mechanics, two on the demonstration of
principles, and one of problems; besides treatises on sound and speech,
on light and colours, on the tides, on the composition of continuous
quantity, on the motions of animals, and on the military art. On the
subject of his salary, he makes the following curious observations:--

"I say nothing," says he, "on the amount of my salary; being convinced
that, as I am to live upon it, the graciousness of his highness would
not deprive me of any of those comforts, of which, however, I feel the
want of less than many others; and, therefore, I say nothing more on the
subject. Finally, on the title and profession of my service, I should
wish that, to the title of mathematician, his highness would add that of
philosopher, as I profess to have studied a greater number of years in
philosophy, than months in pure mathematics; and how I have profited by
it, and if I can or ought to deserve this title, I may let their
highnesses see, as often as it shall please them to give me an
opportunity of discussing such subjects in their presence with those who
are most esteemed in this knowledge."

During the progress of this negotiation, Galileo went to Venice, on a
visit to a friend, in the month of April or May 1609. Here he learned,
from common rumour, that a Dutchman had presented to prince Maurice of
Nassau an optical instrument, which possessed the singular property of
causing distant objects to appear nearer the observer. This Dutchman was
Hans or John Lippershey, who, as has been clearly proved by the late
Professor Moll of Utrecht,[8] was in the possession of a telescope made
by himself so early as 2d October 1608. A few days afterwards, the truth
of this report was confirmed by a letter which Galileo received from
James Badorere at Paris, and he immediately applied himself to the
consideration of the subject. On the first night after his return to
Padua, he found, in the doctrines of refraction, the principle which he
sought. He placed at the ends of a leaden tube two spectacle glasses,
both of which were plain on one side, while one of them had its other
side convex, and the other its second side concave, and having applied
his eye to the concave glass, he saw objects pretty large and pretty
near him. This little instrument, which magnified only three times, he
carried in triumph to Venice, where it excited the most intense
interest. Crowds of the principal citizens flocked to his house to see
the magical toy; and after nearly a month had been spent in gratifying
this epidemical curiosity, Galileo was led to understand from Leonardo
Deodati, the Doge of Venice, that the senate would be highly gratified
by obtaining possession of so extraordinary an instrument. Galileo
instantly complied with the wishes of his patrons, who acknowledged the
present by a mandate conferring upon him for life his professorship at
Padua, and generously raising his salary from 520 to 1000 florins.[9]

     [8] On the First Invention of Telescopes.--_Journ. R. Instit._,
     1831., vol i., p. 496.

     [9] Viviani _Vita del' Galileo_, p. 69.

Although we cannot doubt the veracity of Galileo, when he affirms that
he had never seen any of the Dutch telescopes, yet it is expressly
stated by Fuccarius, that one of these instruments had at this time been
brought to Florence; and Sirturus assures us that a Frenchman, calling
himself a partner of the Dutch inventor, came to Milan in May 1609, and
offered a telescope to the Count de Fuentes. In a letter from Lorenzo
Pignoria to Paolo Gualdo, dated from Padua, on the 31st of August 1609,
it is expressly said, that, at the re-election of the professors,
Galileo had contrived to obtain 1000 florins for life, which was alleged
to be on account of an eye-glass like the one which was sent from
Flanders to the Cardinal Borghese.

In a memoir so brief and general as the present, it would be out of
place to discuss the history of this extraordinary invention. We have no
hesitation in asserting that a method of magnifying distant objects was
known to Baptista Porta and others; but it seems to be equally certain
that an _instrument_ for producing these effects was first constructed
in Holland, and that it was from that kingdom that Galileo derived the
knowledge of its existence. In considering the contending claims, which
have been urged with all the ardour and partiality of national feeling,
it has been generally overlooked, _that a single convex lens_, whose
focal length exceeds the distance at which we examine minute objects,
performs the part of a telescope, when an eye, placed behind it, sees
distinctly the inverted image which it forms. A lens, twenty feet in
focal length, will in this manner magnify twenty times; and it was by
the same principle that Sir William Herschel discovered a new satellite
of Saturn, by using only the mirror of his forty-feet telescope. The
instrument presented to Prince Maurice, and which the Marquis Spinola
found in the shop of John Lippershey, the spectacle maker of Middleburg,
must have been an astronomical telescope consisting of two convex
lenses. Upon this supposition, it differed from that which Galileo
constructed; and the Italian philosopher will be justly entitled to the
honour of having invented that form of the telescope which still bears
his name, while we must accord to the Dutch optician the honour of
having previously invented the astronomical telescope.

The interest which the exhibition of the telescope excited at Venice did
not soon subside: Sirturi[10] describes it as amounting almost to
phrensy. When he himself had succeeded in making one of these
instruments, he ascended the tower of St Mark, where he might use it
without molestation. He was recognised, however, by a crowd in the
street; and such was the eagerness of their curiosity, that they took
possession of the wondrous tube, and detained the impatient philosopher
for several hours, till they had successively witnessed its effects.
Desirous of obtaining the same gratification for their friends, they
endeavoured to learn the name of the inn at which he lodged; but Sirturi
fortunately overheard their inquiries, and quitted Venice early next
morning, in order to avoid a second visitation of this new school of
philosophers. The opticians speedily availed themselves of the new
instrument. Galileo's tube,--or the double eye-glass, or the cylinder,
or the trunk, as it was then called, for Demisiano had not yet given it
the appellation of _telescope_,--was manufactured in great quantities,
and in a very superior manner. The instruments were purchased merely as
philosophical toys, and were carried by travellers into every corner of
Europe.

     [10] De Telescopio.

The art of grinding and polishing lenses was at this time very
imperfect. Galileo, and those whom he instructed, were alone capable of
making tolerable instruments. It appears, from the testimony of Gassendi
and Gærtner, that, in 1634, a good telescope could not be procured in
Paris, Venice, or Amsterdam; and that, even in 1637, there was not one
in Holland which could shew Jupiter's disc well defined.

After Galileo had completed his first instrument, which magnified only
_three_ times, he executed a larger and a better one, with a power of
about _eight_. "At length," as he himself remarks, "sparing neither
labour nor expense," he constructed an instrument so excellent, that it
bore a magnifying power of more than _thirty_ times.

The first celestial object to which Galileo applied his telescope was
the moon, which, to use his own words, appeared as near as if it had
been distant only two semidiameters of the earth. He then directed it to
the planets and the fixed stars, which he frequently observed with
"incredible delight."[11]

     [11] Incredibili animi jucunditate.

The observations which he made upon the moon possessed a high degree of
interest. The general resemblance of its surface to that of our own
globe naturally fixed his attention; and he was soon able to trace, in
almost every part of the lunar disc, ranges of mountains, deep hollows,
and other inequalities, which reverberated from their summits and
margins the rays of the rising sun, while the intervening hollows were
still buried in darkness. The dark and luminous spaces he regarded as
indicating seas and continents, which reflected, in different degrees,
the incidental light of the sun; and he ascribed the phosphorescence, as
it has been improperly called, or the secondary light, which is seen on
the dark limb of the moon in her first and last quarters, to the
reflection of the sun's light from the earth.

These discoveries were ill received by the followers of Aristotle.
According to their preconceived opinions, the moon was perfectly
spherical, and absolutely smooth; and to cover it with mountains, and
scoop it out into valleys, was an act of impiety which defaced the
regular forms which Nature herself had imprinted. It was in vain that
Galileo appealed to the evidence of observation, and to the actual
surface of our own globe. The very irregularities on the moon were, in
his opinion, the proof of divine wisdom; and had its surface been
absolutely smooth, it would have been "but a vast unblessed desert, void
of animals, of plants, of cities, and of men--the abode of silence and
inaction--senseless, lifeless, soulless, and stripped of all those
ornaments which now render it so varied and so beautiful."

In examining the fixed stars, and comparing them with the planets,
Galileo observed a remarkable difference in the appearance of their
discs. All the planets appeared with round globular discs like the moon;
whereas the fixed stars never exhibited any disc at all, but resembled
lucid points sending forth twinkling rays. Stars of all magnitudes he
found to have the same appearance; those of the fifth and sixth
magnitude having the same character, when seen through a telescope, as
Sirius, the largest of the stars, when seen by the naked eye. Upon
directing his telescope to nebulæ and clusters of stars, he was
delighted to find that they consisted of great numbers of stars which
could not be recognised by unassisted vision. He counted no fewer than
_forty_ in the cluster called the _Pleiades_, or _Seven Stars_; and he
has given us drawings of this constellation, as well as of the belt and
sword of Orion, and of the nebula of Præsepe. In the great nebula of the
Milky Way, he descried crowds of minute stars; and he concluded that
this singular portion of the heavens derived its whiteness from still
smaller stars, which his telescope was unable to separate.

Important and interesting as these discoveries were, they were thrown
into the shade by those to which he was led during an accurate
examination of the planets with a more powerful telescope. On the 7th of
January 1610, at one o'clock in the morning, when he directed his
telescope to Jupiter, he observed three stars near the body of the
planet, two being to the east and one to the west of him. They were all
in a straight line, and parallel to the ecliptic, and appeared brighter
than other stars of the same magnitude. Believing them to be fixed
stars, he paid no great attention to their distances from Jupiter and
from one another. On the 8th of January, however, when, from some cause
or other,[12] he had been led to observe the stars again, he found a
very different arrangement of them: all the three were on the west side
of Jupiter, _nearer one another than before_, and almost at equal
distances. Though he had not turned his attention to the extraordinary
fact of the mutual approach of the stars, yet he began to consider how
Jupiter could be found to the east of the three stars, when but the day
before he had been to the west of two of them. The only explanation
which he could give of this fact was, that the motion of Jupiter was
_direct_, contrary to astronomical calculations, and that he had got
before these two stars by his own motion.

     [12] Nescio quo fato ductus.

In this dilemma between the testimony of his senses and the results of
calculation, he waited for the following night with the utmost anxiety;
but his hopes were disappointed, for the heavens were wholly veiled in
clouds. On the 10th, two only of the stars appeared, and both on the
east of the planet. As it was obviously impossible that Jupiter could
have advanced from west to east on the 8th of January, and from east to
west on the 10th, Galileo was forced to conclude that the phenomenon
which he had observed arose from the motion of the stars, and he set
himself to observe diligently their change of place. On the 11th, there
were still only two stars, and both to the east of Jupiter; but the more
eastern star was now _twice as large as the other one_, though on the
preceding night they had been perfectly equal. This fact threw a new
light upon Galileo's difficulties, and he immediately drew the
conclusion, which he considered to be indubitable, "_that there were in
the heavens three stars which revolved round Jupiter, in the same manner
as Venus and Mercury revolve round the sun_." On the 12th of January, he
again observed them in new positions, and of different magnitudes; and,
on the 13th, he discovered a fourth star, which completed the _four_
secondary planets with which Jupiter is surrounded.

Galileo continued his observations on these bodies every clear night
till the 22d of March, and studied their motions in reference to fixed
stars that were at the same time within the field of his telescope.
Having thus clearly established that the four new stars were satellites
or moons, which revolved round Jupiter in the same manner as the moon
revolves round our own globe, he drew up an account of his discovery, in
which he gave to the four new bodies the names of the _Medicean Stars_,
in honour of his patron, Cosmo de Medici, Grand Duke of Tuscany. This
work, under the title of "Nuncius Sidereus," or the "Sidereal
Messenger," was dedicated to the same prince; and the dedication bears
the date of the 24th of March, only two days after he concluded his
observations.

The importance of this great discovery was instantly felt by the enemies
as well as by the friends of the Copernican system. The planets had
hitherto been distinguished from the fixed stars only by their relative
change of place, but the telescope proved them to be bodies so near to
our own globe as to exhibit well-defined discs, while the fixed stars
retained, even when magnified, the minuteness of remote and lucid
points. The system of Jupiter, illuminated by four moons performing
their revolutions in different and regular periods, exhibited to the
proud reason of man the comparative insignificance of the globe he
inhabits, and proclaimed in impressive language that that globe was not
the centre of the universe.

The reception which these discoveries met with from Kepler is highly
interesting, and characteristic of the genius of that great man. He was
one day sitting idle, and thinking of Galileo, when his friend
Wachenfels stopped his carriage at his door, to communicate to him the
intelligence. "Such a fit of wonder," says he, "seized me at a report
which seemed to be so very absurd, and I was thrown into such agitation
at seeing an old dispute between us decided in this way, that between
his joy, my colouring, and the laughter of both, confounded as we were
by such a novelty, we were hardly capable, he of speaking, or I of
listening. On our parting, I immediately began to think how there could
be any addition to the number of the planets without overturning my
'Cosmographic Mystery,' according to which Euclid's five regular solids
do not allow more than six planets round the sun.... I am so far from
disbelieving the existence of the four circumjovial planets, that I long
for a telescope, to anticipate you, if possible, in discovering _two_
round Mars, as the proportion seems to require, _six_ or _eight_ round
Saturn, and perhaps _one_ each round Mercury and Venus."

In a very different spirit did the Aristotelians receive the "Sidereal
Messenger" of Galileo. The principal professor of philosophy at Padua
resisted Galileo's repeated and urgent entreaties to look at the moon
and planets through his telescope; and he even laboured to convince the
Grand Duke that the satellites of Jupiter could not possibly exist.
Sizzi, an astronomer of Florence, maintained that as there were only
_seven_ apertures in the head--_two_ eyes, _two_ ears, _two_ nostrils,
and _one_ mouth--and as there were only _seven_ metals, and _seven_ days
in the week, so there could be only _seven_ planets. He seems, however,
to have admitted the visibility of the four satellites through the
telescope; but he argues, that as they are invisible to the naked eye,
they can exercise no influence on the earth; and being useless, they do
not therefore exist.

A _protegé_ of Kepler's, of the name of Horky, wrote a volume against
Galileo's discovery, after having declared, "that he would never concede
his four new planets to that Italian from Padua, even if he should die
for it." This resolute Aristotelian was at no loss for arguments. He
asserted that he had examined the heavens _through Galileo's own glass_,
and that no such thing as a satellite existed round Jupiter. He
affirmed, that he did not more surely know that he had a soul in his
body, than that reflected rays are the sole cause of Galileo's erroneous
observations; and that the only use of the new planets was to gratify
Galileo's thirst for gold, and afford to himself a subject of
discussion.

When Horky first presented himself to Kepler, after the publication of
this work, the opinion of his patron was announced to him by a burst of
indignation which overwhelmed the astonished author. Horky supplicated
mercy for his offence; and, as Kepler himself informed Galileo, he took
him again into favour, on the condition that Kepler was to show him
Jupiter's satellites, and that Horky was not only to see them, but to
admit their existence.

When the spirit of philosophy had thus left the individuals who bore so
unworthily her sacred name, it was fortunate for science that it found a
refuge among princes. Notwithstanding the reiterated logic of his
philosophical professor at Padua, Cosmo de Medici preferred the
testimony of his senses to the syllogisms of his instructor. He observed
the new planets several times, along with Galileo, at Pisa; and when he
parted with him, he gave him a present worth more than 1000 florins, and
concluded that liberal arrangement to which we have already referred.

As philosopher and principal mathematician to the Grand Duke of Tuscany,
Galileo now took up his residence at Florence, with a salary of 1000
florins. No official duties, excepting that of lecturing occasionally to
sovereign princes, were attached to this appointment; and it was
expressly stipulated that he should enjoy the most perfect leisure to
complete his treatises on the constitution of the universe, on
mechanics, and on local motion. The resignation of his professorship in
the university of Padua, which was the necessary consequence of his new
appointment, created much dissatisfaction: but though many of his former
friends refused at first to hold any communication with him, this
excitement gradually subsided; and the Venetian senate at last
appreciated the feelings, as well as the motives, which induced a
stranger to accept of promotion in his native land.

While Galileo was enjoying the reward and the fame of his great
discovery, a new species of enmity was roused against him. Simon Mayer,
an astronomer of no character, pretended that he had discovered the
satellites of Jupiter before Galileo, and that his first observation was
made on the 29th of December, 1609. Other astronomers announced the
discovery of new satellites: Scheiner reckoned five, Rheita nine, and
others found even so many as twelve: these satellites, however, were
found to be only fixed stars. The names of _Vladislavian_, _Agrippine_,
_Uranodavian_, and _Ferdinandotertian_, which were hastily given to
these common telescopic stars, soon disappeared from the page of
science, and even the splendid telescopes of modern times have not been
able to add another gem to the diadem of Jupiter.

A modern astronomer of no mean celebrity has, even in the present day,
endeavoured to rob Galileo of this staple article of his reputation.
From a careless examination of the papers of our celebrated countryman,
Thomas Harriot, which Baron Zach had made in 1784, at Petworth, the seat
of Lord Egremont, this astronomer has asserted[13] that Harriot first
observed the satellites of Jupiter on the 16th of January, 1610; and
continued his observations till the 25th of February, 1612. Baron Zach
adds the following extraordinary conclusion:--"Galileo pretends to have
discovered them on the 7th of January, 1610; so that it is not
improbable that Harriot was likewise the first discoverer of these
attendants of Jupiter." In a communication which I received from Dr
Robertson, of Oxford, in 1822,[14] he informed me that he had examined a
portion of Harriot's papers, entitled, "De Jovialibus Planetis;" and
that it appears, from two pages of these papers, _that Harriot first
observed Jupiter's satellites on the 17th of October, 1610_. These
observations are accompanied with rough drawings of the positions of the
satellites, and rough calculations of their periodical revolutions. My
friend, Professor Rigaud,[15] who has very recently examined the Harriot
MSS., has confirmed the accuracy of Dr Robertson's observations, and has
thus restored to Galileo the honour of being the first and the sole
discoverer of these secondary planets.

     [13] Berlin Ephemeris, 1788.

     [14] Edin. Phil. Journ. vol. vi. p. 313.

     [15] Life and Correspondence of Dr Bradley, Oxford, 1832, p. 533,
     See also his Supplement. Oxford, 1833, p. 17.




CHAPTER III.

     _Galileo announces his discoveries in Enigmas--Discovers the
     Crescent of Venus--the Ring of Saturn--the Spots on the
     Sun--Similar Observations made in England by Harriot--Claims of
     Fabricius and Scheiner to the discovery of the Solar
     Spots--Galileo's Letters to Velser on the claims of Scheiner--His
     residence at the Villa of Salviati--Composes his work on Floating
     Bodies, which involves him in new controversies._


The great success which attended the first telescopic observations of
Galileo, induced him to apply his best instruments to the other planets
of our system. The attempts which had been made to deprive him of the
honour of some of his discoveries, combined, probably, with a desire to
repeat his observations with better telescopes, led him to announce his
discoveries under the veil of an enigma, and to invite astronomers to
declare, within a given time, if they had observed any new phenomena in
the heavens.

Before the close of 1610, Galileo excited the curiosity of astronomers
by the publication of his first enigma. Kepler and others tried in vain
to decipher it; but in consequence of the Emperor Rodolph requesting a
solution of the puzzle, Galileo sent him the following clue:--

     "Altissimam planetam tergeminam observavi."

     I have observed that the most remote planet is triple.

In explaining more fully the nature of his observation, Galileo remarked
that Saturn was not a single star, but three together, nearly touching
one another. He described them as having no relative motion, and as
having the form of three o's, namely, oOo, the central one being larger
than those on each side of it.

Although Galileo had announced that nothing new appeared in the other
planets, yet he soon communicated to the world another discovery of no
slight interest. The enigmatical letters in which it was concealed
formed the following sentence:--

     "Cynthiæ figuras æmulatur mater Amorum."

     Venus rivals the phases of the moon.

Hitherto, Galileo had observed Venus when her disc was largely
illuminated; but having directed his telescope to her when she was not
far removed from the sun, he saw her in the form of a crescent,
resembling exactly the moon at the same elongation. He continued to
observe her night after night, during the whole time that she could be
seen in the course of her revolution round the sun, and he found that
she exhibited the very same phases which resulted from her motion round
that luminary.

Galileo had long contemplated a visit to the metropolis of Italy, and he
accordingly carried his intentions into effect in the early part of the
year 1611. Here he was received with that distinction which was due to
his great talents and his extended reputation. Princes, Cardinals, and
Prelates hastened to do him honour; and even those who discredited his
discoveries, and dreaded their results, vied with the true friends of
science in their anxiety to see the intellectual wonder of the age.

In order to show the new celestial phenomena to his friends at Rome,
Galileo took with him his best telescope; and as he had discovered the
spots on the sun's surface in October or November 1610, or even
earlier,[16] he had the gratification of exhibiting them to his admiring
disciples. He accordingly erected his telescope in the Quirinal garden,
belonging to Cardinal Bandini; and in April 1611 he shewed them to his
friends in many of their most interesting variations. From their change
of position on the sun's disc, Galileo at first inferred, either that
the sun revolved about an axis, or that other planets, like Venus and
Mercury, revolved so near the sun as to appear like black spots when
they were opposite to his disc. Upon continuing his observations,
however, he saw reason to abandon this hasty opinion. He found that the
spots must be in contact with the surface of the sun,--that their
figures were irregular,--that they had different degrees of
darkness,--that one spot would often divide itself into three or
four,--that three or four spots would often unite themselves into
one,--and that all the spots revolved regularly with the sun, which
appeared to complete its revolution in about twenty-eight days.

     [16] Professor Rigaud is of opinion that Galileo had discovered the
     solar spots at an earlier period than eighteen months before May
     1612.

Previous to the invention of the telescope, spots had been more than
once seen on the sun's disc with the unassisted eye. But even if these
were of the same character as those which Galileo and others observed,
we cannot consider them as anticipations of their discovery by the
telescope. As the telescope was now in the possession of several
astronomers, Galileo began to have many rivals in discovery; but
notwithstanding the claims of Harriot, Fabricius, and Scheiner, it is
now placed beyond the reach of doubt that he was the first discoverer of
the solar spots. From the communication which I received in 1822 from
the late Dr Robertson, of Oxford,[17] it appeared that Thomas Harriot
had observed the solar spots on the 8th of December 1610; but his
manuscripts, in Lord Egremont's possession,[18] incontestably prove that
his regular observations on the spots did not commence till December 1,
1611, although he had seen the spots at the date above mentioned, and
that they were continued till the 18th of January 1613. The
observations which he has recorded are 199 in number, and the accounts
of them are accompanied with rough drawings representing the number,
position, and magnitude of the spots.[19] In the observation of Harriot,
made on the 8th December 1610, before he knew of Galileo's discovery, he
saw three spots on the sun, which he has represented in a diagram. The
sun was then 7° or 8° high, and there was a frost and a mist, which no
doubt acted as a darkening glass. Harriot does not apply the name of
spots to what he noticed in this observation, and he does not enumerate
it among the 199 observations above mentioned. Professor Rigaud[20]
considers it "a misapplication of terms to call such an observation a
discovery;" but, with all the respect which we feel for the candour of
this remark, we are disposed to confer on Harriot the merit of an
original discoverer of the spots on the sun.

     [17] See page 40.

     [18] These interesting MSS. I have had the good fortune of seeing
     in the possession of my much valued friend, the late Professor
     Rigaud of Oxford.

     [19] Edin. Phil. Journ. 1822, vol. vi. p. 317. See Rigaud's Life of
     Bradley, Supplement, p. 31.

     [20] Id. It., p. 37, 38.

Another candidate for the honour of discovering the spots of the sun,
was John Fabricius, who undoubtedly saw them previous to June 1611. The
dedication of the work[21] in which he has recorded his observation,
bears the date of the 13th of June 1611; and it is obvious, from the
work itself, that he had seen the spots about the end of the year 1610;
but as there is no proof that he saw them before October, we are
compelled to assign the priority of the discovery to the Italian
astronomer.

     [21] Joh. Fabricii Phrysii de Maculis in Sole observatis, et
     apparente earum cum Sole conversione, Narratio. Wittemb. 1611.

The claim of Scheiner, professor of mathematics at Ingolstadt, is more
intimately connected with the history of Galileo. This learned
astronomer having, early in 1611, turned his telescope to the sun,
necessarily discovered the spots which at that time covered his disc.
Light flying clouds happened, at the time, to weaken the intensity of
his light, so that he was able to show the spots to his pupils. These
observations were not published till January 1612; and they appeared in
the form of three letters, addressed to Mark Velser, one of the
magistrates of Augsburg, under the signature of _Appelles post Tabulam_.
Scheiner, who, many years afterwards, published an elaborate work on
the subject, adopted the same idea which had at first occurred to
Galileo--that the spots were the dark sides of planets revolving round
and near the sun.[22]

     [22] It does not appear from the history of solar observations at
     what time, and by whom, coloured glasses were first introduced for
     permitting the eye to look at the sun with impunity. Fabricius was
     obviously quite ignorant of the use of coloured glasses. He
     observed the sun when he was in the horizon, and when his
     brilliancy was impaired by the interposition of thin clouds and
     floating vapours; and he advises those who may repeat his
     observations to admit at first to the eye a small portion of the
     sun's light, till it is gradually accustomed to its full splendour.
     When the sun's altitude became considerable, Fabricius gave up his
     observations, which he often continued so long that he was scarcely
     able, for two days together, to see objects with their usual
     distinctness. Fabricius speaks of observing the sun by admitting
     his rays through a small _hole_ into a dark room, and receiving his
     image on paper; but he says nothing about a lens or a telescope
     being applied to the hole; and he does not say that he saw the
     spots of the sun in this way. Harriot also viewed the solar spots
     when the sun was near the horizon, or was visible through "thick
     layer and thin cloudes," or through thin mist. On December 21,
     1611, at a quarter past 2 P.M., he observed the spots when the sky
     was perfectly clear, but his "sight was after dim for an houre."

     Scheiner, in his "Appelles post Tabulam," describes four different
     ways of viewing the spots; one of which is by the _interposition of
     blue or green glasses_. His first method was to observe the sun
     near the horizon; the second was to view him through a transparent
     cloud; the third was to look at him through his telescope with a
     blue or a green glass of a proper thickness, and plane on both
     sides, or to use a thin blue glass when the sun was covered with a
     thin vapour or cloud; and the fourth method was to begin and
     observe the sun at his margin, till the eye gradually reached the
     middle of his disc.

On the publication of Scheiner's letters, Velser transmitted a copy of
them to his friend Galileo, with the request that he would favour him
with his opinion of the new phenomena. After some delay, Galileo
addressed three letters to Velser, in which he combated the opinions of
Scheiner on the cause of the spots. The first of these letters was dated
the 4th of May 1612;[23] but though the controversy was carried on in
the language of mutual respect and esteem, it put an end to the
friendship which had existed between the two astronomers. In these
letters Galileo showed that the spots often dispersed like vapours or
clouds; that they sometimes had a duration of only one or two days, and
at other times of thirty or forty days; that they contracted in their
breadth when they approached the sun's limb, without any diminution of
their length; that they describe circles parallel to each other; that
the monthly rotation of the sun again brings the same spots into view;
and that they are seldom seen at a greater distance than 30° from the
sun's equator. Galileo likewise discovered on the sun's disc _faculæ_,
or _luculi_, as they were called, which differ in no respect from the
common ones but in their being brighter than the rest of the sun's
surface.[24]

     [23] The original of this letter is in the British Museum.

     [24] See Istoria e Dimonstrazioni, intorno alle macchie solare.
     _Roma_, 1616. See Opere di Galileo, vol, v., p. 131-293.

In the last of the letters which our author addressed to Velser, and
which was written in December 1612, he recurs to his former discovery of
the elongated shape, or rather the triple structure, of Saturn. The
singular figure which he had observed in this planet had entirely
disappeared; and he evidently announces the fact to Velser, lest it
should be used by his enemies to discredit the accuracy of his
observations. "Looking on Saturn," says he, "within these few days, I
found it solitary, without the assistance of its accustomed stars, and,
in short, perfectly round and defined like Jupiter; and such it still
remains. Now, what can be said of so strange a metamorphosis? Are the
two smaller stars consumed like the spots on the sun? Have they suddenly
vanished and fled? or has Saturn devoured his own children? or was the
appearance indeed fraud and illusion, with which the glasses have for so
long a time mocked me, and so many others who have often observed with
me? Now, perhaps, the time is come to revive the withering hopes of
those who, guided by more profound contemplations, have followed all the
fallacies of the new observations, and recognised their impossibilities.
I cannot resolve what to say in a chance so strange, so new, and so
unexpected; the shortness of the time, the unexampled occurrence, the
weakness of my intellect, and the terror of being mistaken, have greatly
confounded me." Although Galileo struggled to obtain a solution of this
mystery, yet he had not the good fortune to succeed. He imagined that
the two smaller stars would reappear, in consequence of the supposed
revolution of the planet round its axis; but the discovery of the ring
of Saturn, and of the obliquity of its plane to the ecliptic, was
necessary to explain the phenomena which were so perplexing to our
author.

The ill health to which Galileo was occasionally subject, and the belief
that the air of Florence was prejudicial to his complaints, induced him
to spend much of his time at Selve, the villa of his friend Salviati.
This eminent individual had ever been the warmest friend of Galileo, and
seems to have delighted in drawing round him the scientific genius of
the age. He was a member of the celebrated Lyncæan Society, founded by
Prince Frederigo Cesi; and though he is not known as the author of any
important discovery, yet he has earned, by his liberality to science, a
glorious name, which will be indissolubly united with the immortal
destiny of Galileo.

The subject of floating bridges having been discussed at one of the
scientific parties which had assembled at the house of Salviati, a
difference of opinion arose respecting the influence of the shape of
bodies on their disposition to float or to sink in a fluid. Contrary to
the general opinion, Galileo undertook to prove that it depended on
other causes; and he was thus led to compose his discourse on floating
bodies,[25] which was published in 1612, and dedicated to Cosmo de
Medici. This work contains many ingenious experiments, and much acute
reasoning in support of the true principles of hydrostatics; and it is
now chiefly remarkable as a specimen of the sagacity and intellectual
power of its author. Like all his other works, it encountered the most
violent opposition; and Galileo was more than once summoned into the
field to repel the aggressions of his ignorant and presumptuous
opponents. The first attack upon it was made by Ptolemy Nozzolini, in a
letter to Marzemedici, Archbishop of Florence;[26] and to this Galileo
replied in a letter addressed to his antagonist.[27] A more elaborate
examination of it was published by Lodovico delle Colombe, and another
by M. Vincenzo di Grazia. To these attacks, a minute and overwhelming
answer was printed in the name of Benedetti Castelli, the friend and
pupil of Galileo; but it was discovered, some years after Galileo's
death, that he was himself the author of this work.[28]

     [25] Discorso intorno alle cose che stanno in su l'acqua, o che in
     quella si muovono. Opere di Galileo, vol. ii. pp. 165-311.

     [26] Opere di Galileo, vol. ii. pp. 355-367.

     [27] Ibid. 367-390.

     [28] These three treatises occupy the whole of the third volume of
     the Opere di Galileo.




CHAPTER IV.

     _Galileo treats his opponents with severity and sarcasm--He is
     aided by the sceptics of the day--The Church party the most
     powerful--Galileo commences the attack, and is answered by Caccini,
     a Dominican--Galileo's Letter to the Grand Duchess of Tuscany, in
     support of the motion of the Earth and the stability of the Sun---
     Galileo visits Rome--Is summoned before the Inquisition, and
     renounces his opinions as heretical--The Inquisition denounces the
     Copernican System--Galileo has an audience of the Pope, but still
     maintains his opinions in private society--Proposes to find out the
     Longitude at Sea by means of Jupiter's Satellites--His negociation
     on this subject with the Court of Spain--Its failure--He is unable
     to observe the three Comets of 1618, but is involved in the
     controversy to which they gave rise._


The current of Galileo's life had hitherto flowed in a smooth and
unobstructed channel. He had now attained the highest objects of earthly
ambition. His discoveries had placed him at the head of the great men of
the age; he possessed a professional income far beyond his wants, and
even beyond his anticipations; and, what is still dearer to a
philosopher, he enjoyed the most perfect leisure for carrying on and
completing his discoveries. The opposition which these discoveries
encountered, was to him more a subject for triumph than for sorrow.
Prejudice and ignorance were his only enemies; and if they succeeded for
a while in harassing his march, it was only to lay a foundation for
fresh achievements. He who contends for truths which he has himself been
permitted to discover, may well sustain the conflict in which
presumption and error are destined to fall. The public tribunal may
neither be sufficiently pure nor enlightened to decide upon the issue;
but he can appeal to posterity, and reckon with confidence on "its sure
decree."

The ardour of Galileo's mind, the keenness of his temper, his clear
perception of truth, and his inextinguishable love of it, combined to
exasperate and prolong the hostility of his enemies. When argument
failed to enlighten their judgment, and reason to dispel their
prejudices, he wielded against them his powerful weapons of ridicule
and sarcasm; and in this unrelenting warfare, he seems to have forgotten
that Providence had withheld from his enemies those very gifts which he
had so liberally received. He who is allowed to take the start of his
species, and to penetrate the veil which conceals from common minds the
mysteries of nature, must not expect that the world will be patiently
dragged at the chariot wheels of his philosophy. Mind has its inertia as
well as matter; and its progress to truth can only be insured by the
gradual and patient removal of the obstructions which surround it.

The boldness--may we not say the recklessness--with which Galileo
insisted upon making proselytes of his enemies, served but to alienate
them from the truth. Errors thus assailed speedily entrench themselves
in general feelings, and become embalmed in the virulence of the
passions. The various classes of his opponents marshalled themselves for
their mutual defence. The Aristotelian professors, the temporising
Jesuits, the political churchmen, and that timid but respectable body
who at all times dread innovation, whether it be in religion or in
science, entered into an alliance against the philosophical tyrant who
threatened them with the penalties of knowledge.

The party of Galileo, though weak in numbers, was not without power and
influence. He had trained around him a devoted band, who idolised his
genius and cherished his doctrines. His pupils had been appointed to
several of the principal professorships in Italy. The enemies of
religion were on this occasion united with the Christian philosopher;
and there were, even in these days, many princes and nobles who had felt
the inconvenience of ecclesiastical jurisdiction, and who secretly
abetted Galileo in his crusade against established errors.

Although these two parties had been long dreading each others power, and
reconnoitring each others position, yet we cannot exactly determine
which of them hoisted the first signal for war. The church party,
particularly its highest dignitaries, were certainly disposed to rest on
the defensive. Flanked on one side by the logic of the schools, and on
the other by the popular interpretation of Scripture, and backed by the
strong arm of the civil power, they were not disposed to interfere with
the prosecution of science, however much they may have dreaded its
influence. The philosophers, on the contrary, united the zeal of
innovators with that firmness of purpose which truth alone can inspire.
Victorious in every contest, they were flushed with success, and they
panted for a struggle in which they knew they must triumph.

In this state of warlike preparation Galileo addressed a letter, in
1613, to his friend and pupil, the Abbé Castelli, the object of which
was to prove that the Scriptures were not intended to teach us science
and philosophy. Hence he inferred, that the language employed in the
sacred volume in reference to such subjects should be interpreted only
in its common acceptation; and that it was in reality as difficult to
reconcile the Ptolemaic as the Copernican system to the expressions
which occur in the Bible.

A demonstration was about this time made by the opposite party, in the
person of Caccini, a Dominican friar, who made a personal attack upon
Galileo from the pulpit. This violent ecclesiastic ridiculed the
astronomer and his followers, by addressing them sarcastically in the
sacred language of Scripture--"Ye men of _Galilee_, why stand ye here
looking up into heaven?" But this species of warfare was disapproved of
even by the church; and Luigi Maraffi, the general of the Dominicans,
not only apologised to Galileo, who had transmitted to him a formal
complaint against Caccini, but expressed the acuteness of his own
feelings on being implicated in the "brutal conduct of thirty or forty
thousand monks."

From the character of Caccini, and the part which he afterwards played
in the persecution of Galileo, we can scarcely avoid the opinion that
his attack from the pulpit was intended as a snare for the unwary
philosopher. It roused Galileo from his wonted caution; and stimulated,
no doubt, by the nature of the answer which he received from Maraffi, he
published a long letter of seventy pages, defending and illustrating his
former views respecting the influence of scriptural language on the two
contending systems. As if to give the impress of royal authority to this
new appeal, he addressed it to Christian, Grand Duchess of Tuscany, the
mother of Cosmo; and in this form it seems to have excited a new
interest, as if it had expressed the opinion of the grand ducal family.
These external circumstances gave additional weight to the powerful and
unanswerable reasoning which this letter contains; and it was scarcely
possible that any man, possessed of a sound mind, and willing to learn
the truth, should refuse his assent to the judicious views of our
author. He expresses his belief that the Scriptures were designed to
instruct mankind respecting their salvation, and that the faculties of
our minds were given us for the purpose of investigating the phenomena
of nature. He considers Scripture and nature as proceeding from the same
divine author, and, therefore, incapable of speaking a different
language; and he points out the absurdity of supposing that professors
of astronomy will shut their eyes to the phenomena which they discover
in the heavens, or will refuse to believe those deductions of reason
which appeal to their judgment with all the power of demonstration. He
supports these views by quotations from the ancient fathers; and he
refers to the dedication of Copernicus's own work to the Roman Pontiff,
Paul III., as a proof that the Pope himself did not regard the new
system of the world as hostile to the sacred writings. Copernicus, on
the contrary, tells his Holiness, that the reason of inscribing to him
his new system was, that the authority of the Pontiff might put to
silence the calumnies of some individuals, who attacked it by arguments
drawn from passages of Scripture twisted for their own purpose.

It was in vain to meet such reasoning by any other weapons than those of
the civil power. The enemies of Galileo saw that they must either crush
the dangerous innovation, or allow it the fullest scope; and they
determined upon an appeal to the inquisition. Lorini, a monk of the
Dominican order, had already denounced to this body Galileo's letter to
Castelli; and Caccini, bribed by the mastership of the convent of St
Mary of Minerva, was invited to settle at Rome for the purpose of
embodying the evidence against Galileo.

Though these plans had been carried on in secret, yet Galileo's
suspicions were excited; and he obtained leave from Cosmo to go to Rome
about the end of 1615.[29] Here he was lodged in the palace of the
Grand Duke's ambassador, and kept up a constant correspondence with the
family of his patron at Florence; but, in the midst of this external
splendour, he was summoned before the inquisition to answer for the
heretical doctrines which he had published. He was charged with
maintaining the motion of the earth, and the stability of the sun--with
teaching this doctrine to his pupils--with corresponding on the subject
with several German mathematicians--and with having published it, and
attempted to reconcile it to Scripture, in his letters to Mark Velser in
1612. The inquisition assembled to consider these charges on the 25th of
February 1615; and it was decreed that Galileo should be enjoined by
Cardinal Bellarmine to renounce the obnoxious doctrines, and to pledge
himself that he would neither teach, defend, nor publish them in future.
In the event of his refusing to acquiesce in this sentence, it was
decreed that he should be thrown into prison. Galileo did not hesitate
to yield to this injunction. On the day following, the 26th of February,
he appeared before Cardinal Bellarmine, to renounce his heretical
opinions; and, having declared that he abandoned the doctrine of the
earth's motion, and would neither defend nor teach it, in his
conversation or in his writings, he was dismissed from the bar of the
inquisition.

     [29] It is said that Galileo was cited to appear at Rome on this
     occasion; and the opinion is not without foundation.

Having thus disposed of Galileo, the inquisition conceived the design of
condemning the whole system of Copernicus as heretical. Galileo, with
more hardihood than prudence, remained at Rome for the purpose of giving
his assistance in frustrating this plan; but there is reason to think
that he injured by his presence the very cause which he meant to
support. The inquisitors had determined to put down the new opinions;
and they now inserted among the prohibited books Galileo's letters to
Castelli and the Grand Duchess, Kepler's epitome of the Copernican
theory, and Copernicus's own work on the revolutions of the heavenly
bodies.

Notwithstanding these proceedings, Galileo had an audience of the Pope,
Paul V., in March 1616. He was received very graciously, and spent
nearly an hour with his Holiness. When they were about to part, the Pope
assured Galileo, that the congregation were not disposed to receive upon
light grounds any calumnies which might be propagated by his enemies,
and that, as long as he occupied the papal chair, he might consider
himself as safe.

These assurances were no doubt founded on the belief that Galileo would
adhere to his pledges; but so bold and inconsiderate was he in the
expression of his opinions, that even in Rome he was continually engaged
in controversial discussions. The following very interesting account of
these disputes is given by Querenghi, in a letter to the Cardinal
D'Este:--

"Your eminence would be delighted with Galileo if you heard him holding
forth, as he often does, in the midst of fifteen or twenty, all
violently attacking him, sometimes in one house, sometimes in another.
But he is armed after such fashion that he laughs all of them to scorn;
and even if the novelty of his opinions prevents entire persuasion, he
at least convicts of emptiness most of the arguments with which his
adversaries endeavour to overwhelm him. He was particularly admirable on
Monday last in the house of Signor Frederico Ghisilieri; and what
especially pleased me was, that before replying to the contrary
arguments, he amplified and enforced them with new grounds of great
plausibility, so as to leave his adversaries in a more ridiculous
plight, when he afterwards overturned them all."

The discovery of Jupiter's satellites suggested to Galileo a new method
of finding the longitude at sea. Philip III. had encouraged astronomers
to direct their attention to this problem, by offering a reward for its
solution; and in those days, when new discoveries in science were
sometimes rejected as injurious to mankind, it was no common event to
see a powerful sovereign courting the assistance of astronomers in
promoting the commercial interests of his empire. Galileo seems to have
regarded the solution of this problem as an object worthy of his
ambition; and he no doubt anticipated the triumph which he would obtain
over his enemies, if the Medicean stars, which they had treated with
such contempt, could be made subservient to the great interests of
mankind. During his residence at Rome in 1615 and 1616, Galileo had
communicated his views on this subject to the Comte di Lemos, the
Viceroy of Naples, who had presided over the council of the Spanish
Indies. This nobleman advised him to apply to the Spanish minister the
Duke of Lerma; and, through the influence of the Grand Duke Cosmo, his
ambassador at the court of Madrid was engaged to manage the affair. The
anxiety of Galileo on this subject was singularly great. He assured the
Tuscan ambassador that, in order to accomplish this object, "he was
ready to leave all his comforts, his country, his friends, and his
family, to cross over into Spain, and to stay as long as he might be
wanted at Seville or at Lisbon, or wherever it might be convenient to
communicate a knowledge of his method." The lethargy of the Spanish
court seems to have increased with the enthusiasm of Galileo; and though
the negotiations were occasionally revived for ten or twelve years, yet
no steps were taken to bring them to a close. This strange
procrastination has been generally ascribed to jealousy or indifference
on the part of Spain; but Nelli, one of Galileo's biographers, declares,
on the authority of Florentine records, that Cosmo had privately
requested from the government the privilege of sending annually to the
Spanish Indies two Leghorn merchantmen free of duty, as a compensation
for the loss of Galileo!

The failure of this negotiation must have been a source of extreme
mortification to the high spirit and sanguine temperament of Galileo.
He had calculated, however, too securely on his means of putting the new
method to a successful trial. The great imperfection of the time-keepers
of that day, and the want of proper telescopes, would have baffled him
in all his efforts, and he would have been subject to a more serious
mortification from the failure and rejection of his plan, than that
which he actually experienced from the avarice of his patron, or the
indifference of Spain. Even in the present day, no telescope has been
invented which is capable of observing at sea the eclipses of Jupiter's
satellites; and though this method of finding the longitude has great
advantages on shore, yet it has been completely abandoned at sea, and
superseded by easier and more correct methods.

In the year 1618, when no fewer than _three_ comets visited our system,
and attracted the attention of all the astronomers of Europe, Galileo
was unfortunately confined to his bed by a severe illness; but, though
he was unable to make a single observation upon these remarkable bodies,
he contrived to involve himself in the controversies which they
occasioned. Marco Guiducci, an astronomer of Florence, and a friend of
Galileo, had delivered a discourse on comets before the Florentine
Academy. The heads of this discourse, which was published in 1619,[30]
were supposed to have been communicated to him by Galileo, and this
seems to have been universally admitted during the controversy to which
it gave rise. The opinion maintained in this treatise, that comets are
nothing but meteors which occasionally appear in our atmosphere, like
halos and rainbows, savours so little of the sagacity of Galileo that we
should be disposed to question its paternity. His inability to partake
in the general interest which these three comets excited, and to employ
his powerful telescope in observing their phenomena, and their
movements, might have had some slight share in the formation of an
opinion which deprived them of their importance as celestial bodies.
But, however this may have been, the treatise of Guiducci afforded a
favourable point of attack to Galileo's enemies, and the dangerous task
was entrusted to Horatio Grassi, a learned Jesuit, who, in a work
entitled _The Astronomical and Philosophical Balance_, criticised the
discourse on comets, under the feigned name of Lotario Sarsi.

     [30] Discorso delle Comete. Printed in the Opere di Galileo, vol.
     vi., pp. 117-191.

Galileo replied to this attack in a volume entitled _Il Saggiatore_, or
_The Assayer_, which, owing to the state of his health, was not
published till the autumn of 1623.[31] This work was written in the form
of a letter to Virginio Cesarini, a member of the Lyncæan Academy, and
master of the chamber to Urban VIII., who had just ascended the papal
throne. It was dedicated to the Pontiff himself, and has been long
celebrated among literary men for the beauty of its language, though it
is doubtless one of the least important of Galileo's writings.

     [31] Printed in the Opere di Galileo, vol. vi., pp. 191-571.




CHAPTER V.

     _Urban VIII., Galileo's friend, raised to the Pontificate--Galileo
     goes to Rome to offer his congratulations--The Pope loads Galileo
     with presents, and promises a Pension to his Son--Galileo in
     pecuniary difficulties, owing to the death of his patron,
     Cosmo--Galileo again rashly attacks the Church, notwithstanding the
     Pope's kindness--He composes his System of the World, to
     demonstrate the Copernican System--Artfully obtains a license to
     print it--Nature of the work--Its influence on the public mind--The
     Pope resolves on suppressing it--Galileo summoned before the
     Inquisition--His Trial--His Defence--His formal abjuration of his
     opinions--Observations on his conduct--The Pope shews great
     indulgence to Galileo, who is allowed to return to his own house at
     Arcetri, as the place of his confinement._


The succession of the Cardinal Maffeo Barberini to the papal throne,
under the name of Urban VIII., was hailed by Galileo and his friends as
an event favourable to the promotion of science. Urban had not only been
the personal friend of Galileo and of Prince Cesi, the founder of the
Lyncæan Academy, but had been intimately connected with that able and
liberal association; and it was therefore deemed prudent to secure his
favour and attachment. If Paul III. had, nearly a century before,
patronised Copernicus, and accepted of the dedication of his great work,
it was not unreasonable to expect that, in more enlightened times,
another Pontiff might exhibit the same liberality to science.

The plan of securing to Galileo the patronage of Urban VIII. seems to
have been devised by Prince Cesi. Although Galileo had not been able for
some years to travel, excepting in a litter, yet he was urged by the
Prince to perform a journey to Rome, for the express purpose of
congratulating his friend upon his elevation to the papal chair. This
request was made in October 1623; and though Galileo's health was not
such as to authorise him to undergo so much fatigue, yet he felt the
importance of the advice, and, after visiting Cesi at Acqua Sparta, he
arrived at Rome in the spring of 1624. The reception which he here
experienced far exceeded his most sanguine expectations. During the two
months which he spent in the capital he was permitted to have no fewer
than six long and gratifying audiences of the Pope. The kindness of his
Holiness was of the most marked description. He not only loaded Galileo
with presents,[32] and promised him a pension for his son Vincenzo, but
he wrote a letter to Ferdinand, who had just succeeded Cosmo as Grand
Duke of Tuscany, recommending Galileo to his particular patronage. "For
we find in him," says he, "not only literary distinction, but the love
of piety; and he is strong in those qualities by which Pontifical
good-will is easily obtained. And now, when he has been brought to this
city to congratulate us on our elevation, we have very lovingly embraced
him; nor can we suffer him to return to the country whither your
liberality recalls him, without an ample provision of Pontifical love.
And that you may know how dear he is to us, we have willed to give him
this honourable testimonial of virtue and piety. And we further
signify, that every benefit which you shall confer upon him, imitating
or even surpassing your father's liberality, will conduce to our
gratification."

     [32] A fine painting in gold, and a silver medal, and "a good
     quantity of agnus dei."

Not content with thus securing the friendship of the Pope, Galileo
endeavoured to bespeak the good-will of the Cardinals towards the
Copernican system. He had, accordingly, many interviews with several of
these dignitaries; and he was assured, by Cardinal Hohenzoller, that in
a representation which he had made to the Pope on the subject of
Copernicus, he stated to his Holiness, "that as all the heretics
considered that system as undoubted, it would be necessary to be very
circumspect in coming to any resolution on the subject." To this remark
his Holiness replied--"that the church had not condemned this system;
and that it should not be condemned as heretical, but only as rash;" and
he added, "that there was no fear of any person undertaking to prove
that it must necessarily be true."

The recent appointment of the Abbé Castelli, the friend and pupil of
Galileo, to be mathematician to the Pope, was an event of a most
gratifying nature; and when we recollect that it was to Castelli that
he addressed the famous letter which was pronounced heretical by the
Inquisition, we must regard it also as an event indicative of a new and
favourable feeling towards the friends of science. The opinions of
Urban, indeed, had suffered no change. He was one of the few Cardinals
who had opposed the inquisitorial decree of 1616, and his subsequent
demeanour was in every respect conformable to the liberality of his
early views. The sincerity of his conduct was still further evinced by
the grant of a pension of one hundred crowns to Galileo, a few years
after his visit to Rome; though there is reason to think that this
allowance was not regularly paid.

The death of Cosmo, whose liberality had given him both affluence and
leisure, threatened Galileo with pecuniary difficulties. He had been
involved in a "great load of debt," owing to the circumstances of his
brother's family; and, in order to relieve himself, he had requested
Castelli to dispose of the pension of his son Vincenzo. In addition to
this calamity he was now alarmed at the prospect of losing his salary as
an extraordinary professor at Pisa. The great youth of Ferdinand, who
was scarcely of age, induced Galileo's enemies, in 1629, to raise
doubts respecting the payment of a salary to a professor who neither
resided nor lectured in the university; but the question was decided in
his favour, and we have no doubt that the decision was facilitated by
the friendly recommendation of the Pope, to which we have already
referred.

Although Galileo had made a narrow escape from the grasp of the
Inquisition, yet he was never sufficiently sensible of the lenity which
he experienced. When he left Rome in 1616, under the solemn pledge of
never again teaching the obnoxious doctrine, it was with a hostility
against the church, suppressed but deeply cherished; and his resolution
to propagate the heresy seems to have been coeval with the vow by which
he renounced it. In the year 1618, when he communicated his theory of
the tides to the Archduke Leopold, he alludes in the most sarcastic
manner to the conduct of the church. The same hostile tone, more or
less, pervaded all his writings, and, while he laboured to sharpen the
edge of his satire, he endeavoured to guard himself against its effects,
by an affectation of the humblest deference to the decisions of
theology. Had Galileo stood alone, his devotion to science might have
withdrawn him from so hopeless a contest; but he was spurred on by the
violence of a party. The Lyncæan Academy never scrupled to summon him
from his researches. They placed him in the forlorn hope of their
combat, and he at last fell a victim to the rashness of his friends.

But whatever allowance we may make for the ardour of Galileo's temper,
and the peculiarity of his position; and however we may justify and even
approve of his past conduct, his visit to Urban VIII., in 1624, placed
him in a new relation to the church, which demanded on his part a new
and corresponding demeanour. The noble and generous reception which he
met with from Urban, and the liberal declaration of Cardinal Hohenzoller
on the subject of the Copernican system, should have been regarded as
expressions of regret for the past, and offers of conciliation for the
future. Thus honoured by the head of the church, and befriended by its
dignitaries, Galileo must have felt himself secure against the
indignities of its lesser functionaries, and in the possession of the
fullest license to prosecute his researches and publish his discoveries,
provided he avoided that dogma of the church which, even in the present
day, it has not ventured to renounce. But Galileo was bound to the
Romish hierarchy by even stronger ties. His son and himself were
pensioners of the church, and, having accepted of its alms, they owed to
it, at least, a decent and respectful allegiance. The pension thus given
by Urban was not a remuneration which sovereigns sometimes award to the
services of their subjects. Galileo was a foreigner at Rome. The
sovereign of the papal state owed him no obligation; and hence we must
regard the pension of Galileo as a donation from the Roman Pontiff to
science itself, and as a declaration to the Christian world that
religion was not jealous of philosophy, and that the church of Rome was
willing to respect and foster even the genius of its enemies.

Galileo viewed all these circumstances in a different light. He resolved
to compose a work in which the Copernican system should be demonstrated;
but he had not the courage to do this in a direct and open manner. He
adopted the plan of discussing the subject in a dialogue between three
speakers, in the hope of eluding by this artifice the censure of the
church. This work was completed in 1630, but, owing to some
difficulties in obtaining a license to print it, it was not published
till 1632.

In obtaining this license, Galileo exhibited considerable address, and
his memory has not escaped from the imputation of having acted unfairly,
and of having involved his personal friends in the consequences of his
imprudence.

The situation of master of the palace was, fortunately for Galileo's
designs, filled by Nicolo Riccardi, a friend and pupil of his own. This
officer was a sort of censor of new publications, and when he was
applied to on the subject of printing his work, Galileo soon found that
attempts had previously been made to thwart his views. He instantly set
off for Rome, and had an interview with his friend, who was in every
respect anxious to oblige him. Riccardi examined the manuscript, pointed
out some incautious expressions which he considered it necessary to
erase, and returned it with his written approbation, on the
understanding that the alterations he suggested would be made. Dreading
to remain in Rome during the unhealthy season, which was fast
approaching, Galileo returned to Florence, with the intention of
completing the index and dedication, and of sending the MS. to Rome, to
be printed under the care of Prince Cesi. The death of that
distinguished individual, in August 1630, frustrated Galileo's plan, and
he applied for leave to have the book printed in Florence. Riccardi was
at first desirous to examine the MS. again, but, after inspecting only
the beginning and the end of it, he gave Galileo leave to print it
wherever he chose, providing it bore the license of the
Inquisitor-General of Florence, and one or two other persons whom he
named.

Having overcome all these difficulties, Galileo's work was published in
1632, under the title of "_The System of the World of Galileo Galilei_,
&c., in which, in four dialogues concerning the two principal systems of
the world--the Ptolemaic and the Copernican--he discusses,
indeterminately and firmly, the arguments proposed on both sides." It is
dedicated to Ferdinand, Grand Duke of Tuscany, and is prefaced by an
"Address to the prudent reader," which is itself characterised by the
utmost imprudence. He refers to the decree of the Inquisition in the
most insulting and ironical language. He attributes it to passion and to
ignorance, not by direct assertion, but by insinuations ascribed to
others; and he announces his intention to defend the Copernican system,
as a pure mathematical hypothesis, and not as an opinion having an
advantage over that of the stability of the earth absolutely. The
dialogue is conducted by three persons, Salviati, Sagredo, and
Simplicio. Salviati, who is the true philosopher in the dialogue, was
the real name of a nobleman whom we have already had occasion to
mention. Sagredo, the name of another noble friend of Galileo's,
performs a secondary part under Salviati. He proposes doubts, suggests
difficulties, and enlivens the gravity of the dialogue with his wit and
pleasantry. Simplicio is a resolute follower of Ptolemy and Aristotle,
and, with a proper degree of candour and modesty, he brings forward all
the common arguments in favour of the Ptolemaic system. Between the wit
of Sagredo, and the powerful philosophy of Salviati, the peripatetic
sage is baffled in every discussion; and there can be no doubt that
Galileo aimed a more fatal blow at the Ptolemaic system by this mode of
discussing it, than if he had endeavoured to overturn it by direct
arguments.

The influence of this work on the public mind was such as might have
been anticipated. The obnoxious doctrines which it upheld were eagerly
received, and widely disseminated; and the church of Rome became
sensible of the shock which was thus given to its intellectual
supremacy. Pope Urban VIII., attached though he had been to Galileo,
never once hesitated respecting the line of conduct which he felt
himself bound to pursue. His mind was, nevertheless, agitated with
conflicting sentiments. He entertained a sincere affection for science
and literature, and yet he was placed in the position of their enemy. He
had been the personal friend of Galileo, and yet his duty compelled him
to become his accuser. Embarrassing as these feelings were, other
considerations contributed to soothe him. He had, in his capacity of a
Cardinal, opposed the first persecution of Galileo. He had, since his
elevation to the pontificate, traced an open path for the march of
Galileo's discoveries; and he had finally endeavoured to bind the
recusant philosopher by the chains of kindness and gratitude. All these
means, however, had proved abortive, and he was now called upon to
support the doctrine which he had subscribed, and administer the law of
which he was the guardian.

It has been supposed, without any satisfactory evidence, that Urban may
have been influenced by less creditable motives. Salviati and Sagredo
being well-known personages, it was inferred that Simplicio must also
have a representative. The enemies of Galileo are said to have convinced
his Holiness that Simplicio was intended as a portraiture of himself;
and this opinion received some probability from the fact, that the
peripatetic disputant had employed many of the arguments which Urban had
himself used in his discussions with Galileo. The latest biographer of
Galileo[33] regards this motive as necessary to account for "the
otherwise inexplicable change which took place in the conduct of Urban
to his old friend;"--but we cannot admit the truth of this supposition.
The church had been placed in hostility to a powerful and liberal party,
which was adverse to its interests. The dogmas of the Catholic faith had
been brought into direct collision with the deductions of science. The
leader of the philosophic band had broken the most solemn armistice with
the Inquisition: he had renounced the ties of gratitude which bound him
to the Pontiff; and Urban was thus compelled to entrench himself in a
position to which he had been driven by his opponents.

     [33] Library of Useful Knowledge, Life of Galileo, chap. viii.

The design of summoning Galileo before the Inquisition, seems to have
been formed almost immediately after the publication of his book; for
even in August 1632, the preliminary proceedings had reached the ears of
the Grand Duke Ferdinand. The Tuscan ambassador at Rome was speedily
acquainted with the dissatisfaction which his Sovereign felt at these
proceedings; and he was instructed to forward to Florence a written
statement of the charges against Galileo, in order to enable him to
prepare for his defence. Although this request was denied, Ferdinand
again interposed, and transmitted a letter to his ambassador,
recommending the admission of Campanella and Castelli into the
congregation of ecclesiastics by whom Galileo was to be judged.
Circumstances, however, rendered it prudent to withhold this letter.
Castelli was sent away from Rome, and Scipio Chiaramonte, a bigotted
ecclesiastic, was summoned from Pisa to complete the number of the
judges.

It appears from a despatch of the Tuscan minister, that Ferdinand was
enraged at the transaction; and he instructed his ambassador, Niccolini,
to make the strongest representations to the Pope. Niccolini had several
interviews with his Holiness; but all his expostulations were fruitless.
He found Urban highly incensed against Galileo; and his Holiness begged
Niccolini to advise the Archduke not to interfere any farther, as he
would not "get through it with honour." On the 15th of September the
Pope caused it to be intimated to Niccolini, as a mark of his especial
esteem for the Grand Duke, that he was obliged to refer the work to the
Inquisition; but both the prince and his ambassador were declared liable
to the usual censures if they divulged the secret.

From the measures which this tribunal had formerly pursued, it was not
difficult to foresee the result of their present deliberations. They
summoned Galileo to appear before them at Rome, to answer in person the
charges under which he lay. The Tuscan ambassador expostulated warmly
with the court of Rome on the inhumanity of this proceeding. He urged
his advanced age, his infirm health, the discomforts of the journey, and
the miseries of the quarantine,[34] as motives for reconsidering their
decision: But the Pope was inexorable, and though it was agreed to relax
the quarantine as much as possible in his favour, yet it was declared
indispensable that he should appear in person before the Inquisition.

     [34] The communication between Florence and Rome was at this time
     interrupted by a contagious disease which had broken out in
     Tuscany.

Worn out with age and infirmities, and exhausted with the fatigues of
his journey, Galileo arrived at Rome on the 14th of February, 1633. The
Tuscan ambassador announced his arrival in an official form to the
commissary of the holy office, and Galileo awaited in calm dignity the
approach of his trial. Among those who proffered their advice in this
distressing emergency, we must enumerate the Cardinal Barberino, the
Pope's nephew, who, though he may have felt the necessity of an
interference on the part of the church, was yet desirous that it should
be effected with the least injury to Galileo and to science. He
accordingly visited Galileo, and advised him to remain as much at home
as possible, to keep aloof from general society, and to see only his
most intimate friends. The same advice was given from different
quarters; and Galileo, feeling its propriety, remained in strict
seclusion in the palace of the Tuscan ambassador.

During the whole of the trial which had now commenced, Galileo was
treated with the most marked indulgence. Abhorring, as we must do, the
principles and practice of this odious tribunal, and reprobating its
interference with the cautious deductions of science, we must yet admit
that, on this occasion, its deliberations were not dictated by passion,
nor its power directed by vengeance. Though placed at their
judgment-seat as a heretic, Galileo stood there with the recognised
attributes of a sage; and though an offender against the laws of which
they were the guardian, yet the highest respect was yielded to his
genius, and the kindest commiseration to his infirmities.

In the beginning of April, when his examination in person was to
commence, it became necessary that he should be removed to the holy
office; but instead of committing him, as was the practice, to solitary
confinement, he was provided with apartments in the house of the fiscal
of the Inquisition. His table was provided by the Tuscan ambassador, and
his servant was allowed to attend him at his pleasure, and to sleep in
an adjoining apartment. Even this nominal confinement, however,
Galileo's high spirit was unable to brook. An attack of the disease to
which he was constitutionally subject contributed to fret and irritate
him, and he became impatient for a release from his anxiety as well as
from his bondage. Cardinal Barberino seems to have received notice of
the state of Galileo's feelings, and, with a magnanimity which posterity
will ever honour, he liberated the philosopher on his own
responsibility; and in ten days after his first examination, and on the
last day of April, he was restored to the hospitable roof of the Tuscan
ambassador.

Though this favour was granted on the condition of his remaining in
strict seclusion, Galileo recovered his health, and to a certain degree
his usual hilarity, amid the kind attentions of Niccolini and his
family; and when the want of exercise had begun to produce symptoms of
indisposition, the Tuscan minister obtained for him leave to go into the
public gardens in a half-closed carriage.

After the Inquisition had examined Galileo personally, they allowed him
a reasonable time for preparing his defence. He felt the difficulty of
adducing any thing like a plausible justification of his conduct; and he
resorted to an ingenious, though a shallow artifice, which was regarded
by the court as an aggravation of the crime. After his first appearance
before the Inquisition in 1616, he was publicly and falsely charged by
his enemies with having then abjured his opinions; and he was taunted as
a criminal who had been actually punished for his offences. As a
refutation of these calumnies, Cardinal Bellarmine had given him a
certificate in his own handwriting, declaring that he neither abjured
his opinions, nor suffered punishment for them; and that the doctrine of
the earth's motion, and the sun's stability, was only denounced to him
as contrary to Scripture, and as one which could not be defended. To
this certificate the Cardinal did not add, because he was not called
upon to do it, that Galileo was enjoined not _to teach in any manner_
the doctrine thus denounced; and Galileo ingeniously avails himself of
this supposed omission, to account for his having, in the lapse of
fourteen or sixteen years, forgotten the injunction. He assigned the
same excuse for his having omitted to mention this injunction to
Riccardi, and to the Inquisitor-General at Florence, when he obtained
the licence to print his Dialogues. The court held the production of
this certificate to be at once a proof and an aggravation of his
offence, because the certificate itself declared that the obnoxious
doctrines had been pronounced contrary to the Holy Scriptures.

Having duly weighed the confessions and excuses of their prisoner, and
considered the general merits of the case, the Inquisition came to an
agreement upon the sentence which they were to pronounce, and appointed
the 22d of June as the day on which it was to be delivered. Two days
previous to this, Galileo was summoned to appear at the holy office; and
on the morning of the 21st, he obeyed the summons. On the 22d of June he
was clothed in a penitential dress, and conducted to the convent of
Minerva, where the Inquisition was assembled to give judgment. A long
and elaborate sentence was pronounced, detailing the former proceedings
of the Inquisition, and specifying the offences which he had committed
in teaching heretical doctrines, in violating his former pledges, and in
obtaining by improper means a license for the printing of his Dialogues.
After an invocation of the name of our Saviour, and of the Holy Virgin,
Galileo is declared to have brought himself under strong suspicions of
heresy, and to have incurred all the censures and penalties which are
enjoined against delinquents of this kind; but from all these
consequences he is to be held absolved, provided that with a sincere
heart, and a faith unfeigned, he abjures and curses the heresies he has
cherished, as well as every other heresy against the Catholic church. In
order that his offence might not go altogether unpunished, that he might
be more cautious in future, and be a warning to others to abstain from
similar delinquencies, it was also decreed that his Dialogues should be
prohibited by public edict; that he himself should be condemned to the
prison of the Inquisition during their pleasure, and that, in the
course of the next three years, he should recite once a week the seven
penitential psalms.

The ceremony of Galileo's abjuration was one of exciting interest, and
of awful formality. Clothed in the sackcloth of a repentant criminal,
the venerable sage fell upon his knees before the assembled Cardinals;
and laying his hands upon the Holy Evangelists, he invoked the Divine
aid in abjuring and detesting, and vowing never again to teach, the
doctrine of the earth's motion, and of the sun's stability. He pledged
himself that he would never again, either in words or in writing,
propagate such heresies; and he swore that he would fulfil and observe
the penances which had been inflicted upon him.[35] At the conclusion of
this ceremony, in which he recited his abjuration word for word, and
then signed it, he was conveyed, in conformity with his sentence, to the
prison of the Inquisition.

     [35] It has been said, but upon what authority we cannot state,
     that when Galileo rose from his knees, he stamped on the ground,
     and said in a whisper to one of his friends, "_E pur si muove._"
     "It does move, though."--Life of Galileo, Lib. Useful Knowledge,
     part ii. p. 63.

The account which we have now given of the trial and the sentence of
Galileo, is pregnant with the deepest interest and instruction. Human
nature is here drawn in its darkest colouring; and in surveying the
melancholy picture, it is difficult to decide whether religion or
philosophy has been most degraded. While we witness the presumptuous
priest pronouncing infallible the decrees of his own erring judgment, we
see the high-minded philosopher abjuring the eternal and immutable
truths which he had himself the glory of establishing. In the ignorance
and prejudices of the age--in a too literal interpretation of the
language of Scripture--in a mistaken respect for the errors that had
become venerable from their antiquity--and in the peculiar position
which Galileo had taken among the avowed enemies of the church, we may
find the elements of an apology, poor though it be, for the conduct of
the Inquisition. But what excuse can we devise for the humiliating
confession and abjuration of Galileo? Why did this master-spirit of the
age--this high-priest of the stars--this representative of science--this
hoary sage, whose career of glory was near its consummation--why did he
reject the crown of martyrdom which he had himself coveted, and which,
plaited with immortal laurels, was about to descend upon his head? If,
in place of disavowing the laws of Nature, and surrendering in his own
person the intellectual dignity of his species, he had boldly asserted
the truth of his opinions, and confided his character to posterity, and
his cause to an all-ruling Providence, he would have strung up the
hair-suspended sabre, and disarmed for ever the hostility which
threatened to overwhelm him. The philosopher, however, was supported
only by philosophy; and in the love of truth he found a miserable
substitute for the hopes of the martyr. Galileo cowered under the fear
of man, and his submission was the salvation of the church. The sword of
the Inquisition descended on his prostrate neck; and though its stroke
was not physical, yet it fell with a moral influence fatal to the
character of its victim, and to the dignity of science.

In studying with attention this portion of scientific history, the
reader will not fail to perceive that the Church of Rome was driven into
a dilemma, from which the submission and abjuration of Galileo could
alone extricate it. He who confesses a crime and denounces its
atrocity, not only sanctions but inflicts the punishment which is
annexed to it. Had Galileo declared his innocence, and avowed his
sentiments, and had he appealed to the past conduct of the Church
itself, to the acknowledged opinions of its dignitaries, and even to the
acts of its pontiffs, he would have at once confounded his accusers, and
escaped from their toils. After Copernicus, himself a catholic priest,
had _openly_ maintained the motion of the earth, and the stability of
the sun:--after he had dedicated the work which advocated these opinions
to Pope Paul III., on the express ground that the _authority of the
pontiff_ might silence the calumnies of those who attacked these
opinions by arguments drawn from Scripture:--after the Cardinal
Schonberg and the Bishop of Culm had urged Copernicus to publish the new
doctrines;--and after the Bishop of Ermeland had erected a monument to
commemorate his great discoveries;--how could the Church of Rome have
appealed to its pontifical decrees as the ground of persecuting and
punishing Galileo? Even in later times, the same doctrines had been
propagated with entire toleration: Nay, in the very year of Galileo's
first persecution, Paul Anthony Foscarinus, a learned Carmelite monk,
wrote a pamphlet, in which he illustrates and defends the mobility of
the earth, and endeavours to reconcile to this new doctrine the passages
of Scripture which had been employed to subvert it. This very singular
production was dated from the Carmelite convent at Naples; was dedicated
to the very reverend Sebastian Fantoni, general of the Carmelite order;
and, sanctioned by the ecclesiastical authorities, it was published at
Naples in 1615, the very year of the first persecution of Galileo.

Nor was this the only defence of the Copernican system which issued from
the bosom of the Church. Thomas Campanella, a Calabrian monk, published,
in 1622, "_An Apology for Galileo_," and he even dedicates it to D.
Boniface, Cardinal of Cajeta. Nay, it appears from the dedication, that
he undertook the work at the command of the Cardinal, and that the
examination of the question had been entrusted to the Cardinal by the
Holy Senate. After an able defence of his friend, Campanella refers, at
the conclusion of his apology, to the suppression of Galileo's writings,
and justly observes, that the effect of such a measure would be to make
them more generally read, and more highly esteemed. The boldness of the
apologist, however, is wisely tempered with the humility of the
ecclesiastic, and he concludes his work with the declaration, that in
all his opinions, whether written or to be written, he submits himself
to the opinions of the Holy Mother Church of Rome and to the judgment of
his superiors.

By these proceedings of the dignitaries, as well as the clergy of the
Church of Rome, which had been tolerated for more than a century, the
decrees of the pontiffs against the doctrine of the earth's motion were
virtually repealed; and Galileo might have pleaded them with success in
arrest of judgment. Unfortunately, however, for himself and for science,
he acted otherwise. By admitting their authority, he revived in fresh
force these obsolete and obnoxious enactments; and, by yielding to their
power, he riveted for another century the almost broken chains of
spiritual despotism.

It is a curious fact in the annals of heresy and sedition, that opinions
maintained with impunity by one individual, have, in the same age,
brought others to the stake or to the scaffold. The results of deep
research or extravagant speculation seldom provoke hostility, when
meekly announced as the deductions of reason or the convictions of
conscience. As the dreams of a recluse or of an enthusiast, they may
excite pity or call forth contempt; but, like seed quietly cast into the
earth, they will rot and germinate according to the vitality with which
they are endowed. But, if new and startling opinions are thrown in the
face of the community--if they are uttered in triumph or in insult--in
contempt of public opinion, or in derision of cherished errors, they
lose the comeliness of truth in the rancour of their propagation; and
they are like seed scattered in a hurricane, which only irritates and
blinds the husbandman. Had Galileo concluded his _System of the World_
with the quiet peroration of his apologist Campanella, and dedicated it
to the Pope, it might have stood in the library of the Vatican, beside
the cherished though equally heretical volume of Copernicus.

In the abjuration of his opinions by Galileo, Pope Urban VII. did not
fail to observe the full extent of his triumph; and he exhibited the
utmost sagacity in the means which he employed to secure it. While he
endeavoured to overawe the enemies of the church by the formal
promulgation of Galileo's sentence and abjuration, and by punishing the
officials who had assisted in obtaining the license to print his work,
he treated Galileo with the utmost lenity, and yielded to every request
that was made to diminish, and almost suspend, the constraint under
which he lay. The sentence of abjuration was ordered to be publicly read
at several universities. At Florence the ceremonial was performed in the
church of Santa Croce, and the friends and disciples of Galileo were
especially summoned to witness the public degradation of their master.
The inquisitor at Florence was ordered to be reprimanded for his
conduct; and Riccardi, the master of the sacred palace, and Ciampoli,
the secretary of Pope Urban himself, were dismissed from their
situations.

Galileo had remained only four days in the prison of the Inquisition,
when, on the application of Niccolini, the Tuscan ambassador, he was
allowed to reside with him in his palace. As Florence still suffered
under the contagious disease which we have already mentioned, it was
proposed that Sienna should be the place of Galileo's confinement, and
that his residence should be in one of the convents of that city.
Niccolini, however, recommended the palace of the Archbishop Piccolomoni
as a more suitable residence; and though the Archbishop was one of
Galileo's best friends, the Pope agreed to the arrangement, and in the
beginning of July Galileo quitted Rome for Sienna.

After having spent nearly six months under the hospitable roof of his
friend, with no other restraint than that of being confined to the
limits of the palace, Galileo was permitted to return to his villa near
Florence under the same restrictions; and as the contagious disease had
disappeared in Tuscany, he was able in the month of December to re-enter
his own house at Arcetri, where he spent the remainder of his days.




CHAPTER VI.

     _Galileo loses his favourite Daughter--He falls into a state of
     melancholy and ill health--Is allowed to go to Florence for its
     recovery in 1638--But is prevented from leaving his House or
     receiving his Friends--His friend Castelli permitted to visit him
     in the presence of an Officer of the Inquisition--He composes his
     celebrated Dialogues on Local Motion--Discovers the Moon's
     Libration--Loses the sight of one Eye--The other Eye attacked by
     the same Disease--Is struck blind--Negociates with the Dutch
     Government respecting his Method of finding the Longitude--He is
     allowed free intercourse with his Friends--His Illness and Death in
     1642--His Epitaph--His Social, Moral, and Scientific Character._


Although Galileo had now the happiness of rejoining his family under
their paternal roof, yet, like all sublunary blessings, it was but of
short duration. His favourite daughter Maria, who along with her sister
had joined the convent of St Matthew in the neighbourhood of Arcetri,
had looked forward to the arrival of her father with the most
affectionate anticipations. She hoped that her filial devotion might
form some compensation for the malignity of his enemies, and she eagerly
assumed the labour of reciting weekly the seven penitentiary psalms
which formed part of her father's sentence. These sacred duties,
however, were destined to terminate almost at the moment they were
begun. She was seized with a fatal illness in the same month in which
she rejoined her parent, and before the month of April she was no more.
This heavy blow, so suddenly struck, overwhelmed Galileo in the deepest
agony. Owing to the decline of his health, and the recurrence of his old
complaints, he was unable to oppose to this mental suffering the
constitutional energy of his mind. The bulwarks of his heart broke down,
and a flood of grief desolated his manly and powerful mind. He felt, as
he expressed it, that he was incessantly called by his daughter--his
pulse intermitted--his heart was agitated with unceasing
palpitations--his appetite entirely left him, and he considered his
dissolution so near at hand, that he would not permit his son Vicenzo to
set out upon a journey which he had contemplated.

From this state of melancholy and indisposition, Galileo slowly, though
partially, recovered, and, with the view of obtaining medical
assistance, he requested leave to go to Florence. His enemies, however,
refused this application, and he was given to understand that any
additional importunities would be visited with a more vigilant
surveillance. He remained, therefore, five years at Arcetri, from 1634
to 1638, without any remission of his confinement, and pursuing his
studies under the influence of a continued and general indisposition.

There is no reason to think that Galileo or his friends renewed their
application to the Church of Rome; but, in 1638, the Pope transmitted,
through the Inquisitor Fariano, his permission that he might remove to
Florence for the recovery of his health, on the condition that he should
present himself at the office of the Inquisitor to learn the terms upon
which this indulgence was granted. Galileo accepted of the kindness thus
unexpectedly proffered. But the conditions upon which it was given were
more severe than he expected. He was prohibited from leaving his house
or admitting his friends; and so sternly was this system pursued, that
he required a special order for attending mass during passion week.

The severity of this order was keenly felt by Galileo. While he remained
at Arcetri, his seclusion from the world would have been an object of
choice, if it had not been the decree of a tribunal; but to be debarred
from the conversation of his friends in Florence--in that city where his
genius had been idolised, and where his fame had become immortal, was an
aggravation of punishment which he was unable to bear. With his
accustomed kindness, the Grand Duke made a strong representation on the
subject to his ambassador at the Court of Rome. He stated that, from his
great age and infirmities, Galileo's career was near its close; that he
possessed many valuable ideas, which the world might lose if they were
not matured and conveyed to his friends; and that Galileo was anxious to
make these communications to Father Castelli, who was then a stipendiary
of the Court of Rome. The Grand Duke commanded his ambassador to see
Castelli on the subject--to urge him to obtain leave from the Pope to
spend a few months in Florence--and to supply him with money and every
thing that was necessary for his journey. Influenced by this kind and
liberal message, Castelli obtained an audience of the Pope, and
requested leave to pay a visit to Florence. Urban instantly suspected
the object of his journey; and, upon Castelli's acknowledging that he
could not possibly refrain from seeing Galileo, he received permission
to visit him in the company of an officer of the Inquisition. Castelli
accordingly went to Florence, and, a few months afterwards, Galileo was
ordered to return to Arcetri.

During Galileo's confinement at Sienna and Arcetri, between 1633 and
1638, his time was principally occupied in the composition of his
"Dialogues on Local Motion," in which he treats of the strength and
cohesion of solid bodies, of the laws of uniform and accelerated
motions, of the motion of projectiles, and of the centre of gravity of
solids. This remarkable work, which was considered by its author as the
best of his productions, was printed by Louis Elzevir, at Amsterdam, and
dedicated to the Count de Noailles, the French ambassador at Rome.
Various attempts to have it printed in Germany had failed; and, in order
to save himself from the malignity of his enemies, he was obliged to
pretend that the edition published in Holland had been printed from a
MS. entrusted to the French ambassador.

Although Galileo had for a long time abandoned his astronomical studies,
yet his attention was directed, about the year 1636, to a curious
appearance in the lunar disc, which is known by the name of the moon's
libration. When we examine with a telescope the outline of the moon, we
observe that certain parts of her disc, which are seen at one time, are
invisible at another. This change or libration is of four different
kinds, viz. the diurnal libration, the libration in longitude, the
libration in latitude, and the spheroidal libration. Galileo discovered
the first of these kinds of libration, and appears to have had some
knowledge of the second; but the third was discovered by Hevelius, and
the fourth by Lagrange.

This curious discovery was the result of the last telescopic
observations of Galileo. Although his right eye had for some years lost
its power, yet his general vision was sufficiently perfect to enable him
to carry on his usual researches. In 1636, however, this affection of
his eye became more serious; and, in 1637, his left eye was attacked
with the same disease. His medical friends at first supposed that
cataracts were formed in the crystalline lens, and anticipated a cure
from the operation of couching. These hopes were fallacious. The disease
turned out to be in the cornea, and every attempt to restore its
transparency was fruitless. In a few months the white cloud covered the
whole aperture of the pupil, and Galileo became totally blind. This
sudden and unexpected calamity had almost overwhelmed Galileo and his
friends. In writing to a correspondent he exclaims, "Alas! your dear
friend and servant has become totally and irreparably blind. These
heavens, this earth, this universe, which by wonderful observation I had
enlarged a thousand times beyond the belief of past ages, are henceforth
shrunk into the narrow space which I myself occupy. So it pleases God;
it shall, therefore, please me also." His friend, Father Castelli,
deplores the calamity in the same tone of pathetic sublimity:--"The
noblest eye," says he, "which nature ever made, is darkened; an eye so
privileged, and gifted with such rare powers, that it may truly be said
to have seen more than the eyes of all that are gone, and to have
opened the eyes of all that are to come."

Although Galileo had been thwarted in his attempt to introduce into the
Spanish marine his new method of finding the longitude at sea, yet he
never lost sight of an object to which he attached the highest
importance. As the formation of correct tables of the motion of
Jupiter's satellites was a necessary preliminary to its introduction, he
had occupied himself for twenty-four years in observations for this
purpose, and he had made considerable progress in this laborious task.
After the publication of his "Dialogues on Motion," in 1636, he renewed
his attempts to bring his method into actual use. For this purpose he
addressed himself to Lorenzo Real, who had been the Dutch
Governor-General in India, and offered the free use of his method to the
States-General of Holland.[36] The Dutch government received this
proposal with an anxious desire to have it carried into effect. At the
instigation of Constantine Huygens, the father of the illustrious
Huygens, and the secretary to the Prince of Orange, they appointed
commissioners to communicate with Galileo; and while they transmitted
him a gold chain as a mark of their esteem, they at the same time
assured him, that if his plan should prove successful it should not pass
unrewarded. The commissioners entered into an active correspondence with
Galileo, and had even appointed one of their number to communicate
personally with him in Italy. Lest this, however, should excite the
jealousy of the court of Rome, Galileo objected to the arrangement, so
that the negociation was carried on solely by correspondence.

     [36] It is a curious fact that Morin had about this time proposed
     to determine the longitude by the moon's distance from a fixed
     star, and that the commissioners assembled in Paris to examine it
     requested Galileo's opinion of its value and practicability.
     Galileo's opinion was highly unfavourable. He saw clearly, and
     explained distinctly, the objection to Morin's method, arising from
     the imperfection of the lunar tables, and the inadequacy of
     astronomical instruments; but he seemed not to be conscious that
     the very same objections applied with even greater force to his own
     method, which has since been supplanted by that of the French
     savant. See Life of Galileo, Library of Useful Knowledge, p. 94.

It was at this time that Galileo was struck with blindness. His friend
and pupil, Renieri, undertook in this emergency to arrange and complete
his observations and calculations; but before he had made much progress
in the arduous task, each of the four commissioners died in succession,
and it was with great difficulty that Constantine Huygens succeeded in
renewing the scheme. It was again obstructed, however, by the death of
Galileo; and when Renieri was about to publish, by the order of the
Grand Duke, the "Ephemeris," and "Tables of the Jovian Planets," he was
attacked with a mortal disease, and the manuscripts of Galileo, which he
was on the eve of publishing, were never more heard of. By such a series
of misfortunes were the plans of Galileo and of the States-General
completely overthrown. It is some consolation, however, to know that
neither science nor navigation suffered any severe loss. Notwithstanding
the perfection of our present tables of Jupiter's satellites, and of the
astronomical instruments by which their eclipses may be observed, the
method of Galileo is still impracticable at sea.

In consequence of the strict seclusion to which Galileo had been
subjected, he was in the practice of dating his letters from his prison
at Arcetri; but after he had lost the use of his eyes, the Inquisition
seems to have relaxed its severity, and to have allowed him the freest
intercourse with his friends. The Grand Duke of Tuscany paid him
frequent visits; and among the celebrated strangers who came from
distant lands to see the ornament of Italy, were Gassendi, Deodati, and
our illustrious countryman Milton. During the last three years of his
life, his eminent pupil Viviani formed one of his family; and in October
1641, the celebrated Torricelli, another of his pupils, was admitted to
the same distinction.

Though the powerful mind of Galileo still retained its vigour, yet his
debilitated frame was exhausted with mental labour. He often complained
that his head was too busy for his body; and the continuity of his
studies was frequently broken with attacks of hypochondria, want of
sleep, and acute rheumatic pains. Along with these calamities, he was
afflicted with another still more severe--with deafness almost total;
but though he was now excluded from all communication with the external
world, yet his mind still grappled with the material universe, and while
he was studying the force of percussion, and preparing for a
continuation of his "Dialogues on Motion," he was attacked with fever
and palpitation of the heart, which, after continuing two months,
terminated fatally on the 8th of January 1642, in the 78th year of his
age.

Having died in the character of a prisoner of the Inquisition, this
odious tribunal disputed his right of making a will, and of being buried
in consecrated ground. These objections, however, were withdrawn; but
though a large sum was subscribed for erecting a monument to him in the
church of Santa Croce, in Florence, the Pope would not permit the design
to be carried into execution. His sacred remains were, therefore,
deposited in an obscure corner of the church, and remained for more than
thirty years unmarked with any monumental tablet. The following epitaph,
given without any remark in the Leyden edition of his Dialogues, is, we
presume, the one which was inscribed on a tablet in the church of Santa
Croce:--


                 GALILÆO GALILÆI Florentino,
             Philosopho et Geometræ vere lynceo,
                        Naturæ Oedipo,
          Mirabilium semper inventorum machinatori,
            Qui inconcessa adhuc mortalibus gloria
                   Cælorum provincias auxit
                Et universo dedit incrementum:
               Non enim vitreos spherarum orbes
                Fragilesque stellas conflavit:
                   Sed æterna mundi corpore
               Mediceæ beneficentiæ dedicavit,
              Cujus inextincta gloriæ cupiditas
                      Ut oculos nationum
                     Sæculorumque omnium
                       Videre doceret,
                  Proprios impendit oculos.
              Cum jam nil amplius haberet natura
                      Quod ipse videret.
      Cujus inventa vix intra rerum limites comprehensa
            Firmamentum ipsum non solum continet,
                      Sed etiam recipit.
           Qui relictis tot scientiarum monumentis
              Plura secum tulit, quam reliquit.
                          Gravi enim
                Sed nondum affecta senectute,
                   Novis contemplationibus
                  Majorem gloriam affectans
                Inexplebilem sapientiæ animam
                     Immaturo nobis obitu
                          Exhalavit
                         Anno Domini
                           MCXLII.
                          Ætatis suæ
                           LXXVIII.



At his death, in 1703, Viviani purchased his property, with the charge
of erecting a monument over Galileo's remains and his own. This design
was not carried into effect till 1737, at the expense of the family of
Nelli, when both their bodies were disinterred, and removed to the site
of the splendid monument which now covers them. This monument contains
the bust of Galileo, with figures of Geometry and Astronomy. It was
designed by Giulio Foggini. Galileo's bust was executed by Giovanni
Battista Foggini; the figure of Astronomy by Vincenzio Foggini, his son;
and that of Geometry by Girolamo Ticciati.

Galileo's house at Arcetri still remains. In 1821 it belonged to one
Signor Alimari, having been preserved in the state in which it was left
by Galileo; it stands very near the convent of St Matthew, and about a
mile to the S. E. of Florence. An inscription by Nelli, over the door of
the house, still remains.

The character of Galileo, whether we view him as a member of the social
circle, or as a man of science, presents many interesting and
instructive points of contemplation. Unfortunate, and to a certain
extent immoral, in his domestic relations, he did not derive from that
hallowed source all the enjoyments which it generally yields; and it was
owing to this cause, perhaps, that he was more fond of society than
might have been expected from his studious habits. His habitual
cheerfulness and gaiety, and his affability and frankness of manner,
rendered him an universal favourite among his friends. Without any of
the pedantry of exclusive talent, and without any of that ostentation
which often marks the man of limited though profound acquirements,
Galileo never conversed upon scientific or philosophical subjects except
among those who were capable of understanding them. The extent of his
general information, indeed, his great literary knowledge, but, above
all, his retentive memory, stored with the legends and the poetry of
ancient times, saved him from the necessity of drawing upon his own
peculiar studies for the topics of his conversation.

Galileo was not less distinguished for his hospitality and benevolence;
he was liberal to the poor, and generous in the aid which he
administered to men of genius and talent, who often found a comfortable
asylum under his roof. In his domestic economy he was frugal without
being parsimonious. His hospitable board was ever ready for the
reception of his friends; and, though he was himself abstemious in his
diet, he seems to have been a lover of good wines, of which he received
always the choicest varieties out of the Grand Duke's cellar. This
peculiar taste, together with his attachment to a country life, rendered
him fond of agricultural pursuits, and induced him to devote his leisure
hours to the cultivation of his vineyards.

In his personal appearance Galileo was about the middle size, and of a
square-built, but well-proportioned, frame. His complexion was fair, his
eyes penetrating, and his hair of a reddish hue. His expression was
cheerful and animated, and though his temper was easily ruffled, yet the
excitement was transient, and the cause of it speedily forgotten.

One of the most prominent traits in the character of Galileo was his
invincible love of truth, and his abhorrence of that spiritual despotism
which had so long brooded over Europe. His views, however, were too
liberal, and too far in advance of the age which he adorned; and however
much we may admire the noble spirit which he evinced, and the personal
sacrifices which he made, in his struggle for truth, we must yet lament
the hotness of his zeal and the temerity of his onset. In his contest
with the Church of Rome, he fell under her victorious banner; and though
his cause was that of truth, and hers that of superstition, yet the
sympathy of Europe was not roused by his misfortunes. Under the
sagacious and peaceful sway of Copernicus, astronomy had effected a
glorious triumph over the dogmas of the Church; but under the bold and
uncompromising sceptre of Galileo all her conquests were irrecoverably
lost.

The scientific character of Galileo, and his method of investigating
truth, demand our warmest admiration. The number and ingenuity of his
inventions, the brilliant discoveries which he made in the heavens, and
the depth and beauty of his researches respecting the laws of motion,
have gained him the admiration of every succeeding age, and have placed
him next to Newton in the lists of original and inventive genius. To
this high rank he was doubtless elevated by the inductive processes
which he followed in all his inquiries. Under the sure guidance of
observation and experiment, he advanced to general laws; and if Bacon
had never lived, the student of nature Would have found, in the writings
and labours of Galileo, not only the boasted principles of the inductive
philosophy, but also their practical application to the highest efforts
of invention and discovery.




LIFE OF TYCHO BRAHE.




CHAPTER I.

     _Tycho's Birth, Family, and Education--An Eclipse of the Sun turns
     his attention to Astronomy--Studies Law at Leipsic--But pursues
     Astronomy by stealth--His Uncle's Death--He returns to Copenhagen,
     and resumes his Observations--Revisits Germany--Fights a Duel, and
     loses his Nose--Visits Augsburg, and meets Hainzel--Who assists him
     in making a large Quadrant--Revisits Denmark--And is warmly
     received by the King--He settles at his Uncle's Castle of
     Herritzvold--His Observatory and Laboratory--Discovers the new Star
     in Cassiopeia--Account of this remarkable Body--Tycho's Marriage
     with a Peasant Girl--Which irritates his Friends--His Lectures on
     Astronomy--He visits the Prince of Hesse--Attends the Coronation of
     the Emperor Rudolph at Ratisbon--He returns to Denmark._


Among the distinguished men who were destined to revive the sciences,
and to establish the true system of the universe, Tycho Brahe holds a
conspicuous place. He was born on the 14th December 1546, at Knudstorp,
the estate of his ancestors, which is situated near Helsingborg, in
Scania, and was the eldest son and the second child of a family of five
sons and five daughters. His father, Otto Brahe, who was descended from
a noble Swedish family, was in such straitened circumstances, that he
resolved to educate his sons for the military profession; but Tycho
seems to have disliked the choice that was made for him; and his next
brother, Steno, who appears to have had a similar feeling, exchanged the
sword for the more peaceful occupation of Privy Councillor to the King.
The rest of his brothers, though of senatorial rank, do not seem to have
extended the renown of their family; but their youngest sister, Sophia,
is represented as an accomplished mathematician, and is said to have
devoted her mind to astronomy as well as to the astrological reveries of
the age.

George Brahe, the brother of Otto, having no children of his own,
resolved to adopt and to educate one of his nephews. On the birth of
Tycho, accordingly, he was desirous of having him placed under his
wife's care; but his parents could not be prevailed upon to part with
their child till after the birth of Steno, their second son.

Having been instructed in reading and writing under proper masters,
Tycho began the study of Latin in his seventh year; and, in opposition
to his father's views, he prosecuted it for five years under private
teachers, from whom he received also occasional instruction in poetry
and the belles lettres.

In April 1559, about three years after his father's death, Tycho was
sent to the University of Copenhagen, to study rhetoric and philosophy,
with the view of preparing for the study of the law, and qualifying
himself for some of those political offices which his rank entitled him
to expect. In this situation he contracted no fondness for any
particular study; but after he had been sixteen months at college, an
event occurred which directed all the powers of his mind to the science
of astronomy. The attention of the public had been long fixed on a great
eclipse of the sun, which was to happen on the 21st August 1560; and as
in those days a phenomenon of this kind was linked with the destinies of
nations as well as of individuals, the interest which it excited was as
intense as it was general. Tycho watched its arrival with peculiar
anxiety. He read the astrological diaries of the day, in which its
phases and its consequences were described; and when he saw the sun
darkened at the very moment that had been predicted, and to the very
extent that had been delineated, he resolved to make himself master of a
science which was capable of predicting future events, and especially
that branch of it which connected these events with the fortunes and
destinies of man. With this view he purchased the _Tabulæ Bergenses_,
calculated by John Stadius, and began with ardour the study of the
planetary motions.

When Tycho had completed his course at Copenhagen, he was sent, in
February 1562, under the charge of a tutor to study jurisprudence at
Leipsic. Astronomy, however, engrossed all his thoughts; and he had no
sooner escaped from the daily surveillance of his master, than he rushed
with headlong impetuosity into his favourite pursuits. With his pocket
money he purchased astronomical books, which he read in secret; and by
means of a celestial globe, the size of his fist, he made himself
acquainted with the stars, and followed them night after night through
the heavens, when sleep had lulled the vigilance of his preceptor. By
means of the Ephemerides of Stadius, he learned to distinguish the
planets, and to trace them through their direct and retrograde
movements; and having obtained the Alphonsine and Prutenic Tables, and
compared his own calculations and observations with those of Stadius, he
observed great differences in the results, and from that moment he seems
to have conceived the design of devoting his life to the accurate
construction of tables, which he justly regarded as the basis of
astronomy.

With this view, he applied himself secretly to the study of arithmetic
and geometry; and, without the assistance of a master, he acquired that
mathematical knowledge which enabled him to realise these early
aspirations. His ardour for astronomy was still farther inflamed, and
the resolution which it inspired still farther strengthened, by the
great conjunction of Jupiter and Saturn, which took place in August
1563. The calculated time of this phenomenon differed considerably from
the true time which was observed; and in determining the instant of
conjunction Tycho felt in the strongest manner the imperfection of the
instruments which he used. For this purpose he employed a sort of
compass, one leg of which was directed to one planet and the second to
the other planet or fixed star; and, by measuring the angular opening
between them, he determined the distance of the two celestial bodies. By
this rude contrivance he found that the Alphonsine Tables erred a whole
month in the time of conjunction, while the Copernican ones were at
least several days in error. To this celebrated conjunction Tycho
ascribed the great plague which in subsequent years desolated Europe,
because it took place in the beginning of _Leo_, and not far from the
nebulous stars of _Cancer_, two of the zodiacal signs which are reckoned
by Ptolemy "suffocating and pestilent!"

There dwelt at this time at Leipsic an ingenious artisan named
Scultetus, who was employed by Homelius, the professor of mathematics in
that city, to assist him in the construction of his instruments. Having
become acquainted with this young man, Tycho put into his hand a wooden
radius, such as was recommended by Gemma Frisius, for the purpose of
having it divided in the manner adopted by Homelius; and with this
improved instrument he made a great number of astronomical observations
out of his window, without ever exciting the suspicions of his tutor.

Having spent three years at Leipsic, he was about to make the tour of
Germany, when, in consequence of his uncle's death, he was summoned to
his native country to inherit the fortune which had been left him. He
accordingly quitted Leipsic about the middle of May 1565, and after
having arranged his domestic concerns in Denmark, he continued his
astronomical observations with the radius constructed for him by
Scultetus. The ardour with which he pursued his studies gave great
umbrage to his friends as well as to his relations. He was reproached
for having abandoned the profession of the law; his astronomical
observations were ridiculed as not only useless but degrading, and,
among his numerous connexions, his maternal uncle, Steno Bille, was the
only one who applauded him for following the bent of his genius. Under
these uncomfortable circumstances he resolved to quit his country, and
pay a visit to the most interesting cities of Germany.

At Wittemberg, where he arrived in April 1566, he resumed his
astronomical observations; but, in consequence of the plague having
broken out in that city, he removed to Rostoch in the following autumn.
Here an accident occurred which had nearly deprived him of his life. On
the 10th December he was invited to a wedding feast; and, among other
guests, there was present a noble countryman of his own, Manderupius
Pasbergius. Some difference having arisen between them on this occasion,
they parted with feelings of mutual displeasure. On the 27th of the same
month they met again at some festive games, and having revived their
former quarrel, they agreed to settle their differences by the sword.
They accordingly met at 7 o'clock in the evening of the 29th, and fought
in total darkness. In this blind combat, Manderupius cut off the whole
of the front of Tycho's nose, and it was fortunate for astronomy that
his more valuable organs were defended by so faithful an outpost. The
quarrel, which is said to have originated in a difference of opinion
respecting their mathematical acquirements, terminated here; and Tycho
repaired his loss by cementing upon his face a nose of gold and silver,
which is said to have formed a good imitation of the original.

During the years 1567 and 1568, Tycho continued to reside at Rostoch,
with the exception of a few months, during which he made a rapid journey
into Denmark. He lived in a house in the college of the Jesuits, which
he had rented on account of its fitness for celestial observations; but,
though he intended to spend the winter under its roof, he had made no
arrangement respecting his future life, leaving it, as he said, in the
hands of Providence. A desire, however, to visit the south of Germany
induced him to quit Rostoch, and having crossed the Danube, he paid a
visit to Augsburg.

Upon entering this ancient city, Tycho was particularly struck with the
grandeur of its fortifications, the splendour of its private houses, and
the beauty of its fountains; and, after a short residence within its
walls, he was still more delighted with the industry of the people, the
refinement of the higher classes, and the love of literature and science
which was cherished by its wealthy citizens. Among the interesting
acquaintances which he formed at Augsburg, were two brothers, John and
Paul Hainzel, the one a septemvir, and the other the consul or
burgomaster. They were both distinguished by their learning, and both of
them, particularly Paul, were ardent lovers of astronomy. Tycho had
hitherto no other astronomical instrument than the coarse radius which
was made for him by Scultetus, and he waited only for a proper occasion
to have a larger and better instrument constructed for his use. Having
now the command of workmen who could execute his plans, he conceived the
bold design of making a divided instrument which should distinctly
exhibit single minutes of a degree. While he was transferring the first
rude conception of his instrument to paper, Paul Hainzel entered his
study, and was so struck with the grandeur of the plan, that he
instantly undertook to have it executed at his own expense. The
projected instrument was a quadrant of fourteen cubits radius! and Tycho
and his friend entered upon its construction with that intense ardour
which is ever crowned with success.

In the village of Gegginga, about half a mile to the south of the city,
Paul Hainzel had a country house, the garden of which was chosen as the
spot where the quadrant was to be fixed. The best artists in Augsburg,
clockmakers, jewellers, smiths, and carpenters, were engaged to execute
the work, and from the zeal which so novel an instrument inspired, the
quadrant was completed in less than a month. Its size was so great that
twenty men could with difficulty transport it to its place of fixture.
The two principal rectangular radii were beams of oak; the arch which
lay between their extremities was made of solid wood of a particular
kind, and the whole was bound together by twelve beams. It received
additional strength from several iron bands, and the arch was covered
with plates of brass, for the purpose of receiving the 5400 divisions
into which it was to be subdivided. A large and strong pillar of oak,
shod with iron, was driven into the ground, and kept in its place by
solid mason work. To this pillar the quadrant was fixed in a vertical
plane, and steps were prepared to elevate the observer, when stars of a
low altitude required his attention. As the instrument could not be
conveniently covered with a roof, it was protected from the weather by a
covering made of skins, but notwithstanding this and other precautions,
it was broken to pieces by a violent storm, after having remained
uninjured for the space of five years.

As this quadrant was fitted only to determine the altitudes of the
celestial bodies, Tycho constructed a large sextant for the purpose of
measuring their distances. It consisted of two radii, which opened and
shut round a centre, and which were nearly four cubits long, and also of
two arches, one of which was graduated, while the other served to keep
the radii in the same plane. After the radii had been opened or shut
till they nearly comprehended the angle between the stars to be
observed, the adjustment was completed by means of a very fine tangent
screw. With this instrument Tycho made many excellent observations
during his stay at Augsburg. He began also the construction of a wooden
globe about six feet in diameter. Its outer surface was turned with
great accuracy into a sphere, and kept from warping by interior bars of
wood supported at its centre.

After receiving a visit from the celebrated Peter Ramus, who
subsequently fell a victim at the massacre of St Bartholomew, Tycho left
Augsburg, having received a promise from his friend Hainzel that he
would communicate to him the observations made with his large quadrant,
and with the sextant which he had given him in a present. He paid a
visit to Philip Appian in passing through Ingolstadt, and returned to
his native country about the end of 1571.

The fame which he had acquired as an astronomer procured for him a
warmer reception than that which he had formerly experienced. The King
invited him to court, and his friends and admirers loaded him with
kindness. His uncle, Steno Bille, who now lived at the ancient convent
of Herritzvold, and who had always taken a deep interest in the
scientific character of his nephew, not only invited him to his house,
but assigned to him for an observatory the part of it which was best
adapted for that purpose. Tycho cheerfully accepted of this liberal
offer. The immediate proximity of Herritzvold to Knudstorp, rendered
this arrangement peculiarly convenient, and in the house of his uncle he
experienced all that kindness and consideration which natural affection
and a love of science combined to cherish. When Steno learned that the
study of chemistry was one of the pursuits of his nephew, he granted him
a spacious house, a few yards distant from the convent, for his
laboratory. Tycho lost no time in fitting up his observatory, and in
providing his furnaces; and regarding gold and silver and the other
metals as the stars of the earth, he used to represent his two opposite
pursuits as forming only one science, namely, celestial and terrestrial
astronomy.

In the hopes of enriching himself by the pursuits of alchemy, Tycho
devoted most of his attention to those satellites of gold and silver
which now constituted his own system, and which disturbed by their
powerful action the hitherto uniform movements of their primary. His
affections were ever turning to Germany, where astronomers of kindred
views, and artists of surpassing talent were to be found in almost every
city. The want of money alone prevented him from realizing his wishes;
and it was in the hope of attaining the means of travelling, that he in
a great measure forsook his sextants for his crucibles. In order,
however, that he might have one good instrument in his observatory, he
constructed a sextant similar to, but somewhat larger than, that which
he had presented to Hainzel. Its limb was made of solid brass, and was
exquisitely divided into single minutes of a degree. Its radii were
strengthened with plates of brass, and the apparatus for opening and
shutting them was made with great accuracy.

The possession of this instrument was peculiarly fortunate for Tycho,
for an event now occurred which roused him from his golden visions, and
directed all his faculties into their earlier and purer current. On the
11th November 1572, when he was returning to supper from his laboratory,
the clearness of the sky inspired him with the desire of completing some
particular observations. On looking up to the starry firmament he was
surprised to see an extraordinary light in the constellation of
Cassiopeia, which was then above his head. He felt confident that he had
never before observed such a star in that constellation, and
distrusting the evidence of his own senses, he called out the servants
and the peasants, and having received their testimony that it was a huge
star such as they had never seen before, he was satisfied of the
correctness of his own vision. Regarding it as a new and unusual
phenomenon, he hastened to his observatory, adjusted his sextant, and
measured its distances from the nearest stars in Cassiopeia. He noted
also its form, its magnitude, its light, and its colour, and he waited
with great anxiety for the next night that he might determine the
important point whether it was a fixed star, or a body within, or near
to, our own system.

For several years Tycho had been in the practice of calculating, at the
beginning of each year, a sort of almanac for his own use, and in this
he inserted all the observations which he had made on the new star, and
the conclusions which he had drawn from them. Having gone to Copenhagen
in the course of the ensuing spring, he shewed this manuscript to John
Pratensis, a Professor, in whose house he was always hospitably
received. Charles Danzeus, the French ambassador, and a person of great
learning, having heard of Tycho's arrival, invited himself to dine with
him at the house of Pratensis. The conversation soon turned upon the new
star, and Tycho found his companion very sceptical about its existence.
Danzeus was particularly jocular on the subject, and attacked the Danes
for their inattention to so important a science as astronomy. Tycho
received this lecture in good temper, and with the anxious expectation
that a clear sky would enable him to give a practical refutation of the
attack which was made upon his country. The night turned out serene, and
the whole party saw with astonishment the new star under the most
favourable circumstances. Pratensis conceived that it was similar to the
one observed by Hipparchus, and urged Tycho to publish the observations
which he had made upon it. Tycho refused to accede to this request, on
the pretext that his work was not sufficiently perfect; but the true
reason, as he afterwards acknowledged, was, that he considered it would
be a disgrace for a nobleman, either to study such subjects, or to
communicate them to the public. This absurd notion was with some
difficulty overcome, and through the earnest entreaties and assistance
of Pratensis, his work on the new star was published in 1573.

This remarkable body presents to us one of the most interesting
phenomena in astronomy. The date of its first appearance has not been
exactly ascertained. Tycho saw it on the 11th November, but Cornelius
Gemma had seen it on the 9th, Paul Hainzel saw it on the 7th of August
at Augsburg, and Wolfgangus Schulerus observed it at Wittenberg on the
6th. Tycho conjectures that it was first seen on the 5th, and Hieronymus
Munosius asserts that at Valentia, in Spain, it was not seen on the 2d,
when he was shewing that part of the heavens to his pupils. This
singular body continued to be seen during 16 months, and did not
disappear till March 1574. In its appearance it was exactly like a star,
having none of the distinctive marks of a comet. It twinkled strongly,
and grew larger than _Lyra_ or _Sirius_, or any other fixed star. It
seemed to be somewhat larger than _Jupiter_, when he is nearest the
earth, and rivalled _Venus_ in her greatest brightness. In the _first_
month of its appearance it was less than Jupiter; in the _second_ it
equalled him; in the _third_ it surpassed him in splendour; in the
_fourth_ it was equal to _Sirius_; in the _fifth_ to _Lyra_; in the
_sixth_ and _seventh_ to stars of the _second_ magnitude; in the
_eighth_, _ninth_, and _tenth_, to stars of the _third_ magnitude; in
the _eleventh_, _twelfth_, and _thirteenth_, to stars of the _fourth_
magnitude; in the _fourteenth_ and _fifteenth_ to stars of the _fifth_
magnitude; and in the _sixteenth_ month to stars of the _sixth_
magnitude. After this it became so small that it at last disappeared.
Its colour changed also with its size. At first it was white and bright;
in the third month it began to become yellowish; in the fifth it became
reddish like Aldebaran; and in the seventh and eighth it became bluish
like Saturn; growing afterwards duller and duller. Its place in the
heavens was invariable. Its longitude was in the 6th degree and 54th
minute of Taurus; and its latitude 53° 45´ north. Its right ascension
was 0° 26-2/5´ and its declination 61° 46-3/4´. It had no parallax, and
was unquestionably situated in the region of the fixed stars.

After Tycho had published his book, he proposed to travel into Germany
and Italy, but he was seized with a fever, and he had no sooner
recovered from it, than he became involved in a love affair, which
frustrated all his schemes. Although Tycho was afraid of casting a
stain upon his nobility by publishing his observations on the new star,
yet he did not scruple to debase his lineage by marrying a peasant girl
of the village of Knudstorp. This event took place in 1573, and in 1574
his wife gave birth to his daughter Magdalene. Tycho's noble relations
were deeply offended at this imprudent step; and so far did the mutual
animosity of the parties extend, that the King himself was obliged to
effect a reconciliation.

The fame of our author as an astronomer and mathematician was now so
high, that several young Danish nobles requested him to deliver a course
of lectures upon these interesting subjects. This application was
seconded by Pratensis, Danzeus, and all his best friends; but their
solicitations were vain. The King at last made the request in a way
which ensured its being granted, and Tycho delivered a course of
lectures, in which he not only gave a full view of the science of
astronomy, but defended and explained all the reveries of astrology.

Having finished his lectures, and arranged his domestic affairs, he set
out on his projected journey about the beginning of the spring of 1575,
leaving behind him his wife and daughter, till he should fix upon a
place of permanent residence. The first town which he visited was
Hesse-Cassel, the residence of William, Landgrave of Hesse, whose
patronage of astronomy, and whose skill in making celestial
observations, have immortalized his name. Here Tycho spent eight or ten
delightful days, during which the two astronomers were occupied one half
of the day in scientific conversation, and the other half in
astronomical observations; and he would have prolonged a visit which
gave him so much pleasure, had not the death of one of the Landgrave's
daughters interrupted their labours. Passing through Frankfort, Tycho
went into Switzerland; and, after visiting many cities on his way, he
fixed upon Basle as a place of residence, not only from its centrical
position, but from the salubrity of the air, and the cheapness of
living. From Switzerland he went to Venice, and, in returning through
Germany, he came to Ratisbon, at the time of the congress, which had
been called together on the 1st of November, for the coronation of the
Emperor Rudolph. On this occasion he met with several distinguished
individuals, who were not only skilled in astronomy, but who were among
its warmest patrons. From Ratisbon he passed to Saalfeld, and thence to
Wittemburg, where he saw the parallactic instruments and the wooden
quadrant which had been used by John Pratensis in determining the
latitude of the city, and in measuring the altitudes of the new star.

Tycho was now impatient for home, and he lost no time in returning to
Denmark, where events were awaiting him which frustrated all his
schemes, by placing him in the most favourable situation for promoting
his own happiness, and advancing the interests of astronomy.




CHAPTER II.

     _Frederick II. patronises Tycho--And resolves to establish him in
     Denmark--Grants him the Island of Huen for Life--And Builds the
     splendid Observatory of Uraniburg--Description of the Island, and
     of the Observatory--Account of its Astronomical Instruments--Tycho
     begins his Observations--His Pupils--Tycho is made Canon of
     Rothschild, and receives a large Pension--His Hospitality to his
     Visitors--Ingratitude of Witichius--Tycho sends an Assistant to
     take the Latitude of Frauenburg and Konigsberg--Is visited by
     Ulric, Duke of Mecklenburg--Change in Tycho's fortunes._


The patronage which had been extended to astronomers by several of the
reigning princes of Germany, especially by the Landgrave of Hesse, and
Augustus, Elector of Saxony, had begun to excite a love of science in
the minds of other sovereigns. The King of Denmark seems to have felt it
as a stain upon his character, that the only astronomer in his dominions
should carry on his observations in distant kingdoms and adorn by his
discoveries other courts than his own. With this feeling he sent
ambassadors to Hesse-Cassel to inquire after Tycho, and to intimate to
him his wish that he should return to Denmark, and his anxiety to
promote the advancement of astronomy in his own dominions. Tycho had
left Cassel when these messengers arrived, and had heard nothing of the
King's intentions till he was about to quit Knudstorp with his family
for Basle. At this time he was surprised at the arrival of a noble
messenger, who brought a letter requesting him to meet the King as soon
as possible at Copenhagen. Tycho lost no time in obeying the royal
summons. The King received him with the most flattering kindness. He
offered to give him a grant for life of the island of Huen, between
Denmark and Sweden, and to construct and furnish with instruments, at
his own expense, an observatory, as well as a house for the
accommodation of his family, together with a laboratory for carrying on
his chemical inquiries. Tycho, who truly loved his country, was deeply
affected with the munificence of the royal offer. He accepted of it with
that warmth of gratitude which it was calculated to inspire; and he
particularly rejoiced in the thought that if any success should attend
his future labours, the glory of it would belong to his native land.

The island of Huen is about sxix miles from the coast of Zealand, three
from that of Sweden, and fourteen from Copenhagen. It is six miles in
circumference, and rises into the form of a mountain, which, though very
high, terminates in a plain. It is nowhere rocky, and even in the time
of Tycho it produced the best kinds of grain, afforded excellent
pasturage for horses, cattle, and sheep, and possessed deer, hares,
rabbits, and partridges in abundance. It contained at that time only one
village, with about forty inhabitants.

Having surveyed his new territory, Tycho resolved to build a magnificent
tower in the centre of the elevated plain, which he resolved to call
Uraniburg, or _The City of the Heavens_. Having made the necessary
arrangements, he repaired to the island on the 8th of August, and his
friend Charles Danzeus laid the foundation stone of the new observatory,
which consisted of a slab of porphyry, with the following
inscription:--

     REGNANTE IN DANIA FREDERICO II., CAROLUS DANZÆUS AQUITANUS R. G. I.
     D. L.,[37] DOMUI HUIC PHILOSOPHIÆ, IMPRIMISQUE ASTRORUM
     CONTEMPLATIONI, REGIS DECRETO A NOBILI VIRO TYCHONE BRAHE DE
     KNUDSTRUP EXTRUCTÆ VOTIVUM HUNC LAPIDEM MEMORIÆ ET FELICIS AUSPICII
     ERGO P. ANNO CIC.IC.LXXVI.[38] VI ID. AUGUSTI.

     [37] Regis Gallorum in Dania Legatus.

     [38] Transcriber's footnote: The second Cs in CIC and IC are
     printed reversed in the original.

This ceremony was performed early in the morning of a splendid day, in
which the rising sun threw its blessing upon Frederick, and upon the
party of noblemen and philosophers who had assembled to testify their
love of science. An entertainment was provided for the occasion, and
copious libations of a variety of wines were offered for the success of
the undertaking.

The observatory was surrounded by a rampart, each face of which was
three hundred feet long. About the middle of each face the rampart
became a semicircle, the inner diameter of which was ninety feet. The
height of the rampart was twenty-two feet, and its thickness at the base
twenty. Its four angles corresponded exactly with the four cardinal
points, and at the north and south angles were erected turrets, of
which one was a printing-house, and the other the residence of the
servants. Gates were erected at the east and west angles, and above them
were apartments for the reception of strangers. Within the rampart was a
shrubbery with about three hundred varieties of trees; and at the centre
of each semicircular part of the rampart was a bower or summer-house.
This shrubbery surrounded the flower-garden, which was terminated within
by a circular wall about forty-five feet high, which enclosed a more
elevated area, in the centre of which stood the principal building in
the observatory, and from which four paths led to the above-mentioned
angles, with as many doors for entering the garden.

The principal building was about sixty feet square. The doors were
placed on the east and west sides; and to the north and south fronts
were attached two round towers, whose inner diameter was about
thirty-two feet, and which formed the observatories which had windows in
their roof, that could be opened towards any part of the heavens. The
accommodations for the family were numerous and splendid. Under the
observatory, in the south tower, was the museum and library, and below
this again was the laboratory in a subterraneous crypt, containing
sixteen furnaces of various kinds. Beneath this was a well forty feet
deep, from which water was distributed by syphons to every part of the
building.

Besides the principal building there were other two situated without the
rampart, one to the north, containing a workshop for the construction of
astronomical and other instruments, and the other to the south, which
was occupied as a sort of farm-house. These buildings cost the King of
Denmark 100,000 rix-dollars (£20,000), and Tycho is said to have
expended upon them a similar sum.

As the two towers could not accommodate the instruments which Tycho
required for his observations, he found it necessary to erect, on the
hill about sixty paces to the south of Uraniburg, a subterranean
observatory, in which he might place his larger instruments, which
required to be firmly fixed, and to be protected from the wind and the
weather. This observatory, which he called Stiern-berg, or the mountain,
of the stars, consisted of several crypts, separated by solid walls,
and to these there was a subterranean passage from the laboratory in
Uraniburg. The various buildings which Tycho erected were built in a
regular style of architecture, and were highly ornamented, not only with
external decorations, but with the statues and pictures of the most
distinguished astronomers, from Hipparchus and Ptolemy down to
Copernicus, and with inscriptions and poems in honour of astronomers.

While these buildings were erecting, and after their completion, Tycho
was busily occupied in preparing instruments for observation. These were
of the most splendid description, and the reader will form some notion
of their grandeur and their expense from the following list:--

   _In the south and greater Observatory._

     1. A semicircle of solid iron, covered with brass, four cubits
     radius.

     2. A sextant of the same materials and size.

     3. A quadrant of one and a half cubits radius, and an azimuth
     circle of three cubits.

     4. Ptolemy's parallactic rules, covered with brass, four cubits in
     the side.

     5. The sextant already described in page 134.

     6. Another quadrant, like No. 3.

     7. Zodiacal armillaries of melted brass, and turned out of the
     solid, of three cubits in diameter.

     Near this observatory was a large clock, with one wheel two cubits
     in diameter, and two smaller ones, which, like it, indicated hours,
     minutes, and seconds.

   _In the south and lesser Observatory._

     8. An armillary sphere of brass, with a steel meridian, whose
     diameter was about 4 cubits.

   _In the north Observatory._

     9. Brass parallactic rules, which revolved in azimuth above a brass
     horizon, twelve feet in diameter.

     10. A half sextant, of four cubits radius.

     11. A steel sextant.

     12. Another half sextant, with steel limb, four cubits radius.

     13. The parallactic rules of Copernicus.

     14. Equatorial armillaries.

     15. A quadrant of a solid plate of brass, five cubits in radius,
     shewing every ten seconds.

     16. In the museum was the large globe made at Augsburg, see p. 134.

   _In the Stiern-berg Observatory._

     17. In the central part, a large semicircle, with a brass limb, and
     three clocks, shewing hours, minutes, and seconds.

     18. Equatorial armillaries of seven cubits, with semi-armillaries
     of nine cubits.

     19. A sextant of four cubits radius.

     20. A geometrical square of iron, with an intercepted quadrant of
     five cubits, and divided into fifteen seconds.

     21. A quadrant of four cubits radius, shewing ten seconds, with an
     azimuth circle.

     22. Zodiacal armillaries of brass, with steel meridians, three
     cubits in diameter.

     23. A sextant of brass, kept together by screws, and capable of
     being taken to pieces for travelling with. Its radius was four
     cubits.

     24. A moveable armillary sphere, three cubits in diameter.

     25. A quadrant of solid brass, one cubit radius, and divided into
     minutes by Nonian circles.

     26. An astronomical radius of solid brass, three cubits long.

     27. An astronomical ring of brass, a cubit in diameter.

     28. A small brass astrolabe.

In almost all the instruments now enumerated, the limb was subdivided by
diagonal lines, a method which Tycho first brought into use, but which,
in modern times, has been superseded by the inventions of Nonius and
Vernier.

When Tycho had thus furnished his observatory, he devoted himself to the
examination of the stars; and during the twenty-one years which he spent
in this delightful occupation, he made vast additions to astronomical
science. In order to instruct the young in the art of observation, and
educate assistants for his observatory, he had sometimes under his roof
from six to twelve pupils, whom he boarded and educated. Some of these
were named by the King, and educated at his expense. Others were sent
by different academies and cities; and several, who had presented
themselves of their own accord, were liberally admitted by the generous
astronomer.

As Tycho had spent nearly a ton of gold (about 100,000 dollars) in his
outlay at Uraniburg, his own income was reduced to very narrow limits.
To supply this defect, Frederick gave him an annual pension of 2000
dollars, beside an estate in Norway, and made him Canon of the Episcopal
Church of Rothschild, or Prebend of St Laurence,[39] which had an annual
income of 1000 dollars, and which was burdened only with the expense of
keeping up the chapel containing the Mausolea of the Kings of the family
of Oldenburg.

     [39] This office had been usually conferred on the King's
     Chancellor.

It would be an unprofitable task, and one by no means interesting to the
general reader, to give a detailed history of the various astronomical
observations and discoveries which were made by Tycho during the twenty
years that he spent at Uraniburg. Every phenomenon that appeared in the
heavens, he observed with the greatest care; while he at the same time
carried on regular series of observations for determining the places of
the fixed stars, and for improving the tables of the sun, moon, and
planets. Though almost wholly devoted to these noble pursuits, yet he
kept an open house, and received, with unbounded hospitality, the crowds
of philosophers, nobles, and princes who came to be introduced to the
first astronomer of the age, and to admire the splendid temple which the
Danish Sovereign had consecrated to science.

Among the strangers whom he received under his roof, there were some who
returned his kindness with ingratitude. Among these was Paul Witichius,
a mathematician; who, under the pretence of devoting his whole life to
astronomy, insinuated himself into the utmost familiarity with Tycho.
The unsuspecting astronomer explained to his guest all his inventions,
described all his methods, and even made him acquainted with those views
which he had not realised, and with instruments which he had not yet
executed. When Witichius had thus obtained possession of the methods,
and inventions, and views of Tycho, and had enjoyed his hospitality for
three months, he pretended that he was obliged to return to Germany to
receive an inheritance to which he had succeeded. After quitting
Uraniburg, this ungrateful mathematician neither returned to see Tycho,
nor kept up any correspondence with him; and it was not till five years
after his departure that Tycho learned, from the letters of the Prince
of Hesse to Ranzau, that Witichius had passed through Hesse, and had
described, as his own, the various inventions and methods which had been
shewn to him in Huen.

Being unable to reconcile his own observations with those of Copernicus,
and with the Prutenic Tables, Tycho resolved to obtain new
determinations of the latitude of Frauenburg, in Prussia, where
Copernicus made his observations, and of Konigsberg, to the meridian of
which Rheinhold had adapted his Prutenic Tables. For these purposes he
sent one of his assistants, Elias Morsianus, with a proper instrument,
under the protection of Bylovius, Ambassador of the Margrave of Anspach,
to the King of Denmark, who was returning by sea to Germany; and after
receiving the greatest attention and assistance from the noble Canons
of Ermeland, he determined, from nearly a month's observations on the
sun and stars, that the latitude of Frauenburg was 54° 22½´, in place of
54° 19½´, as given by Copernicus. In like manner he determined that the
latitude of Konigsberg was 54° 43´, in place of 54° 17´, as adopted by
Rheinhold. When Morsianus returned to Huen in July, he brought with him,
as a present to Tycho, from John Hannovius, one of the Canons of
Ermeland, the Ptolemaic Rules, or the Parallactic Instrument which
Copernicus had used and made with his own hands. It consisted of two
equal wooden rules, five cubits long, and divided into 1414 parts. Tycho
preserved this gift as one peculiarly dear to him, and, on the day of
his receiving it, he composed a set of verses in honour of the great
astronomer to whom it belonged.

Among the distinguished visits which were paid to Tycho, we must
enumerate that of Ulric, Duke of Mecklenburg, in 1586. Although his
daughter, Sophia, Queen of Denmark, had already paid two visits to
Uraniburg in the same year, yet such was her love of astronomy, that she
accompanied her father and his wife Elizabeth on this occasion. Ulric
was not only fond of science in general, but had for many years devoted
himself to chemical pursuits, and he was therefore peculiarly gratified
in examining the splendid laboratory and extensive apparatus which Tycho
possessed. It has been said by some of the biographers of Tycho, that
the Landgrave of Hesse visited Uraniburg about this period; but this
opinion is not correct, as it was only his astronomer and optician,
Rothman, who made a journey to Huen in 1591 for the recovery of his
health. Tycho had long carried on a correspondence with this able
astronomer respecting the observations made at the observatory of
Hesse-Cassel, and, during the few months which they now spent together,
they discussed in the amplest manner all the questions which had
previously been agitated. Rothman was astonished at the wonderful
apparatus which he saw at Uraniburg, and returned to his native country
charmed with the hospitality of the Danish astronomer.

Hitherto we have followed Tycho through a career of almost unexampled
prosperity. When he had scarcely reached his thirtieth year he was
established, by the kindness and liberality of his sovereign, in the
most splendid observatory that had ever been erected in Europe; and a
thriving family, an ample income, and a widely extended reputation were
added to his blessings. Of the value of these gifts he was deeply
sensible, and he enjoyed them the more that he received them with a
grateful heart. Tycho was a christian as well as a philosopher. The
powers of his gifted mind have been amply displayed in his astronomical
labours; but we shall now have occasion to witness his piety and
resignation in submitting to an unexpected and an adverse destiny.




CHAPTER III.


     _Tycho's Labours do honour to his Country--Death of Frederick
     II.--James VI. of Scotland visits Tycho at Uraniburg--Christian IV.
     visits Tycho--The Duke of Brunswick's visit to Tycho--The Danish
     Nobility, jealous of his fame, conspire against him--He is
     compelled to quit Uraniburg--And to abandon his Studies--Cruelty of
     the Minister Walchendorp--Tycho quits Denmark with his Family and
     Instruments--Is hospitably received by Count Rantzau--Who
     introduces him to the Emperor Rudolph--The Emperor invites him to
     Prague--He gives him a Pension of 3000 Crowns--And the Castle of
     Benach as a Residence and an Observatory--Kepler visits Tycho--Who
     obtains for him the Appointment of Mathematician to Rudolph._


The love of astronomy which had been so unequivocally exhibited by
Frederick II. and his Royal Consort, inspired their courtiers with at
least an outward respect for science; and among the ministers and
advisers of the King, Tycho reckoned many ardent friends. It was every
where felt that Denmark had elevated herself among the nations of
Europe by her liberality to Tycho; and the peaceful glory which he had
in return conferred upon his country was not of a kind to dissatisfy
even rival nations. In the conquests of science no widow's or orphan's
tears are shed, no captives are dragged from their homes, and no devoted
victims are yoked to the chariot wheels of the triumphant philosopher.
The newly acquired domains of knowledge belong, in right of conquest, to
all nations, and Denmark had now earned the gratitude of Europe by the
magnitude as well as the success of her contingent.

An event, however, now occurred which threatened with destruction the
interests of Danish science. In the beginning of April 1588, Frederick
II. died in the 54th year of his age, and the 29th of his reign. His
remains were conveyed to Rothschild, and deposited in the chapel under
Tycho's care, where a finely executed bust of him was afterwards placed.
His son and successor, Christian IV., was only in the 11th year of his
age, and though his temper and disposition were good, yet Tycho had
reason to be alarmed at the possibility of his discontinuing the
patronage of astronomy. The taste for science, however, which had
sprung up in the Danish Court had extended itself no wider than the
influence of the reigning sovereign. The parasites of royalty saw
themselves eclipsed in the bright renown which Tycho had acquired, and
every new visit to Uraniburg by a foreign prince supplied fresh fuel to
the rancour which had long been smothering in their breasts. The
accession of a youthful king held out to his enemies an opportunity of
destroying the influence of Tycho; and though no adverse step was taken,
yet he had the sagacity to foresee, in "trifles light as air," the
approaching confirmation of his fears. Hope, however, still cheered him
amid his labours, but that hope was founded chiefly on the learning and
character of Nicolas Caasius, the Chancellor of the Kingdom, from whom
he had experienced the warmest attentions.

Among the princes who visited Uraniburg, there were none who conducted
themselves with more condescension and generosity than our own
sovereign, James VI. In the year 1590, when the Scottish King repaired
to Denmark to celebrate his marriage with the Princess Anne, the King's
sister, he paid a visit to Tycho, attended by his councillors and a
large suite of nobility. During the eight days which he spent at
Uraniburg, James carried on long discussions with Tycho on various
subjects, but chiefly on the motion which Copernicus had ascribed to the
earth. He examined narrowly all the astronomical instruments, and made
himself acquainted with the principles of their construction and the
method of using them. He inspected the busts and pictures in the museum,
and when he perceived the portrait of George Buchanan, his own
preceptor, he could not refrain from the strongest expressions of
delight. Upon quitting the hospitable roof of Tycho, James not only
presented him with a magnificent donation, but afterwards gave him his
royal license to publish his works in England during seventy years. This
license was accompanied with the following high eulogium on his
abilities and learning:--"Nor have I become acquainted with these things
only from the relation of others, or from a bare inspection of your
works, but I have seen then before my own eyes, and have heard them with
my own ears, in your residence at Uraniburg, and have drawn them from
the various learned and agreeable conversations which I there held with
you, and which even now affect my mind to such a degree, that it is
difficult to determine whether I recollect them with greater pleasure or
admiration; as I now willingly testify, by this license, to present and
to future generations," &c.

At the request of Tycho, the King also composed and wrote in his own
hand some Latin verses, which were more complimentary than classical.
His Chancellor had also composed some verses of a similar character
during his visit to Tycho. A short specimen of these will be deemed
sufficient by the classical reader:--

    "Vidit et obstupuit Rex Huennum Scoticus almam;
    Miratus clari tot monumenta viri."

In the year 1591, when Christian IV. had reached his 14th year, he
expressed a desire to pay a visit to Uraniburg. He accordingly set out
with a large party, consisting of his three principal senators, and
other councillors and noblemen; and having examined the various
instruments in the observatories and laboratory, he proposed to Tycho
various questions on mechanics and mathematics, but particularly on the
principles of fortification and ship building. Having observed that he
particularly admired a brass globe, which, by means of internal
wheelwork, imitated the diurnal motion of the heavens, the rising and
setting of the sun, and the phases of the moon, Tycho made him a present
of it, and received in return an elegant gold chain, with his Majesty's
picture, with an assurance of his unalterable attachment and protection.

Notwithstanding this assurance, Tycho had already, as we have stated,
begun to suspect the designs of his enemies; and in a letter addressed
to the Landgrave of Hesse, early in 1591, he throws out some hints which
indicated the anxieties that agitated his mind. The Landgrave of Hesse,
as if he had heard some rumours unfavourable to the prospects of Tycho,
requested him to write him respecting the state of the Kingdom, and
concerning his own private affairs. To this letter, which was dated
early in February, Tycho replied about the beginning of April. He
informed the Landgrave that he led a private life in his own island,
exempt from all official functions, and never willingly taking a part in
public affairs. He was desirous of leaving the ambition of public
honours to others, and of devoting himself wholly to the study of
philosophy and astronomy; and he expressed a hope that if he should be
involved in the tumults and troubles of life, either by his own destiny
or by evil counsels, he might be able, by the blessing of God, to
extricate himself by the force of his mind and the integrity of his
life. He comforted himself with the idea that every soil was the country
of a great man, and that wherever he went the blue sky would still be
over his head;[40] and he distinctly states at the close of his letter,
that he had thought of transferring his residence to some other place,
as there were some of the King's councillors who had already begun to
calumniate his studies, and to grudge him his pension from the treasury.

     [40] Omne solum forti patria, et coelum undique supra est.

The causes which led to this change of feeling on the part of Christian
IV.'s advisers have not been explained by the biographers of Tycho. It
has been stated, in general terms, that he had made many enemies, by the
keenness of his temper and the severity of his satire; but I have not
been able to discover any distinct examples of these peculiarities of
his mind. In an event, indeed, which occurred about this time, he
slightly resented a piece of marked incivility on the part of Henry
Julius, Duke of Brunswick, who had married the Princess Eliza of
Denmark; but it is not likely that so trivial an affair, if it were
known at court, could have called down upon him the hostility of the
King's advisers.

The Duke of Brunswick had, in 1590, paid a visit to Uraniburg, and had
particularly admired an antique brass statue of Mercury, about a cubit
long, which Tycho had placed in the roof of the hypocaust or central
crypt of the Stiern-berg observatory. By means of a concealed mechanism,
it moved round in a circular orbit. The Duke requested the statue and
its machinery, which Tycho gave him, on the condition that he should
obtain a model of it, for the purpose of having another executed by a
skilful workman. The Duke not only forgot his promise, but paid no
attention to the letters which were addressed to him. Tycho was justly
irritated at this unprincely conduct, and ordered this anecdote to be
inserted in the description of Uraniburg which he was now preparing for
publication.

In the year 1592, Tycho lost his distinguished friend and correspondent
the Prince of Hesse, and astronomy one of its most active and
intelligent cultivators. His grief on this occasion was deep and
sincere, and he gave utterance to his feelings in an impassioned elegy,
in which he recorded the virtues and talents of his friend. Prince
Maurice, the son and successor of the Landgrave, continued, with the
assistance of able observers, to keep up the reputation of the
observatory of Hesse-Cassel; and the observations which were there made
were afterwards published by Snellius. The extensive and valuable
correspondence between Tycho and the Landgrave was prepared for
publication about the beginning of 1593, and contains also the letters
of Rothman and Rantzau.

For several years the studies of Tycho had been treated with an
unwilling toleration by the Danish Court. Many of the nobles envied the
munificent establishment which he had received from Frederick, and the
liberal pension which he drew from his treasury. But among his most
active enemies were some physicians, who envied his reputation as a
successful and a gratuitous practitioner of the healing art. Numbers of
invalids flocked to Huen, and diseases, which resisted all other methods
of cure, are said to have yielded to the panaceal prescription of the
astrologer. Under the influence of such motives, these individuals
succeeded in exciting against Tycho the hostility of the court. They
drew the public attention to the exhausted state of the treasury. They
maintained that he had possessed too long the estate in Norway, which
might be given to men who laboured more usefully for the commonwealth;
and they accused him of allowing the chapel at Rothschild to fall into
decay. The President of the Council, Christopher Walchendorp, and the
King's Chancellor, were the most active of the enemies of Tycho; and,
having poisoned the mind of their sovereign against the most meritorious
of his subjects, Tycho was deprived of his canonry, his estate in
Norway, and his pension.

Being no longer able to bear the expenses of his establishment in Huen,
and dreading that the feelings which had been excited against him might
be still further roused, so as to deprive him of the Island of Huen
itself, he resolved to transfer his instruments to some other
situation. Notwithstanding this resolution, he remained with his family
in the island, and continued his observations till the spring of 1597,
when he took a house in Copenhagen, and removed to it all his smaller
and more portable instruments, leaving those which were large or fixed
in the crypts of Stiern-berg. His first plan was to remove every thing
from Huen as a measure of security; but the public feeling began to turn
in his favour, and there were many good men in Copenhagen who did not
scruple to reprobate the conduct of the government. The President of the
Council, Walchendorp--a name which, while the heavens revolve, will be
pronounced with horror by astronomers--saw the change of sentiment which
his injustice had produced, and adopted an artful method of sheltering
himself from public odium. In consequence of a quarrel with Tycho, the
recollection of which had rankled in his breast, he dreaded to be the
prime mover in his persecution. He therefore appointed a committee of
two persons, one of whom was Thomas Feuchius, to report to the
government on the nature and utility of the studies of Tycho. These two
individuals were entirely ignorant of astronomy and the use of
instruments; and even if they had not, they would have been equally
subservient to the views of the minister. They reported that the studies
of Tycho were of no value, and that they were not only useless, but
noxious. Armed with this report, Walchendorp prohibited Tycho, in the
King's name, from continuing his chemical experiments; and instigated,
no doubt, by this wicked minister, an attack was made upon himself, and
his shepherd or his steward was injured in the affray. Tycho was
provoked to revenge himself upon his enemies, and the judge was
commanded not to interfere in the matter.

Thus persecuted by his enemies, Tycho resolved to remain no longer in an
ungrateful country. He carried from Huen every thing that was moveable,
and having packed up his instruments, his crucibles, and his books, he
hired a ship to convey them to some foreign land. His wife, his five
sons and four daughters, his male and his female servants, and many of
his pupils and assistants, among whom were Tengnagel, his future
son-in-law, and the celebrated Longomontanus, embarked at Copenhagen,
to seek the hospitality of some better country than their own.

Freighted with the glory of Denmark, this interesting bark made the best
of its way across the Baltic, and arrived safely at Rostoch. Here the
exiled patriarch found many of his early friends, particularly Henry
Bruce, an able astronomer, to whom he had formerly presented one of his
brass quadrants. The approach of the plague, however, prevented Tycho
from making any arrangements for a permanent residence; and, having
received a warm invitation from Count Henry Rantzau, who lived in
Holstein at the Castle of Wandesberg, near Hamburg, he went with all his
family, about the end of 1597, to enjoy the hospitality of his friend.

Though Tycho derived the highest pleasure from the kindness and
conversation of Count Rantzau, yet a cloud overshadowed the future, and
he had yet to seek for a patron and a home. His hopes were fixed on the
Emperor Rudolph, who was not only fond of science, but who was
especially addicted to alchemy and astrology, and his friend Rantzau
promised to have him introduced to the Emperor by proper letters. When
Tycho learned that Rudolph was particularly fond of mechanical
instruments and of chemistry, he resolved to complete and to dedicate to
him his work on the mechanics of astronomy, and to add to it an account
of his chemical labours. This task he soon performed, and his work
appeared in 1598 under the title of _Tychonis Brahe, Astronomiæ
instauratæ Mechanica_. Along with this work he transmitted to the
Emperor a copy of his MS. catalogue of 1000 fixed stars.

With these proofs of his services to science, and instigated by various
letters in his favour, the Emperor Rudolph desired his Vice-Chancellor
to send for Tycho, and to assure him that he would be received according
to his great merits, and that nothing should be wanting to promote his
scientific studies. Leaving his wife and daughters at Wandesberg, and
taking with him his sons and his pupils, Tycho went to Wittemberg; but
having learned that the plague had broken out at Prague, and that the
Emperor had gone to Pilsen, he deferred for a while his journey into
Bohemia.

Early in the spring of 1599, when the pestilence had ceased at Prague,
and the Emperor had returned to his capital, Tycho set out for Bohemia.
On his arrival at Prague, he found a splendid house ready for his
reception, and a kind message from the Emperor, prohibiting him from
paying his respects to him till he had recovered from the fatigues of
his journey. On his presentation to Rudolph, the generous Emperor
received him with the most distinguished kindness. He announced to him
that he was to receive an annual pension of 3000 crowns; that an estate
would as soon as possible be settled upon him and his family and their
successors; that a town house would be provided for him; and that he
might have his choice of various castles and houses in the country as
the site of his observatory and laboratory. The Emperor had also taken
care to provide every thing that was necessary for Tycho's immediate
wants; and so overwhelmed was he with such unexpected kindness, that he
remarked that, as he could not find words to express his gratitude, the
whole heavens would speak for him, and posterity should know what a
refuge his great and good Sovereign had been to the Queen of the Arts.

Among the numerous friends whom Tycho found at Prague, were his
correspondents Coroducius and Hagecius, and his benefactor Barrovitius,
the Emperor's secretary. He was congratulated by them all on his
distinguished reception at court, and was regarded as the Æneas of
science, who had been driven from his peaceful home, and who had carried
with him to the Latium of Germany his wife, his children, and his
household gods. If external circumstances could remove the sorrows of
the past, Tycho must now have been supremely happy. In his spacious
mansion, which had belonged to his friend Curtius, he found a position
for one of his best instruments, and having covered with poetical
inscriptions the four sides of the pedestal on which it stood, in honour
of his benefactors, as well as of former astronomers, he resumed with
diligence his examination of the stars.

When Rudolph saw the magnificent instruments which Tycho had brought
along with him, and had acquired some knowledge of their use, he pressed
him to send to Denmark for the still larger ones which he had left at
Stiern-berg. In the meantime, he gave him the choice of the castles of
Brandisium, Lyssa, and Benach as his country residence; and after
visiting them about the end of May, Tycho gave the preference to Benach,
which was situated upon a rising ground, and commanded an extensive
horizon. It contained splendid and commodious buildings, and was almost,
as he calls it, a small city, situated on the stream Lisor, near its
confluence with the Albis. It stood a little to the east and north of
Prague, and was distant from that city only five German miles, or about
six hours' journey.

On the 20th of August, the Prefect of Brandisium gave Tycho possession
of his new residence. His gratitude to his royal patron was copiously
displayed, not only in a Latin poem written on the occasion, but in
Latin inscriptions which he placed above the doors of his observatory
and his laboratory. In order that he might establish an astronomical
school at Prague, he wrote to Longomontanus, Kepler, Muller, David
Fabricius, and two students at Wittemberg, who were good calculators,
requesting them to reside with him at Benach, as his assistants and
pupils: He at the same time dispatched his destined son-in-law,
Tengnagel, accompanied by Pascal Muleus, to bring home his wife and
daughters from Wandesberg, and his instruments from Huen; and he begged
that Longomontanus would accompany them to Denmark, and return in the
same carriage with them to Bohemia.

Kepler arrived at Prague in January 1600, and, after spending three or
four months at Benach, in carrying on his inquiries and in making
astronomical observations, he returned to Gratz. Tycho had undertaken to
obtain for him the appointment of his assistant. It was arranged that
the Emperor should allow him a hundred florins, on the condition that
the states of Styria would permit him to retain his salary for two
years. This scheme, however, failed, and Kepler was about to study
medicine, and offer himself for a professorship of medicine at Tubingen,
when Tycho undertook to obtain him a permanent appointment from the
Emperor. Kepler, accordingly, returned in September 1601, and, on the
recommendation of his friend, he was named imperial mathematician, on
the condition of assisting Tycho in his observations.

Tycho had experienced much inconvenience in his residence at Benach,
from his ignorance of the language and customs of the country, as well
as from other causes. He was therefore anxious to transfer his
instruments to Prague; and no sooner were his wishes conveyed to the
Emperor than he gave him leave to send them to the royal gardens and the
adjacent buildings. His family and his larger instruments having now
arrived from Huen, the astronomer with his family and his property were
safely lodged in the royal edifice. Having found that there was no house
in Prague more suited for his purposes than that of his late friend
Curtius, the Emperor purchased it from his widow, and Tycho removed into
it on the 25th February 1601.




CHAPTER IV.


     _Tycho resumes his Astronomical Observations--Is attacked with a
     Painful Disease--His Sufferings and Death in 1601--His Funeral--His
     Temper--His Turn for Satire and Raillery--His Piety--Account of his
     Astronomical Discoveries--His Love of Astrology and
     Alchymy--Observations on the Character of the Alchymists--Tycho's
     Elixir--His Fondness for the Marvellous--His Automata and Invisible
     Bells--Account of the Idiot, called Lep, whom he kept as a
     Prophet--History of Tycho's Instruments--His great Brass Globe
     preserved at Copenhagen--Present state of the Island of Huen._


Although Tycho continued in this new position to observe the planets
with his usual assiduity, yet the recollection of his sufferings, and
the inconveniences and disappointments which he had experienced, began
to prey upon his mind, and to affect his health. Notwithstanding the
continued liberality of the Emperor, and the kindness of his friends and
pupils, he was yet a stranger in a distant land. Misfortune was unable
to subdue that love of country which was one of the most powerful of his
affections; and, though its ingratitude might have broken the chain
which bound him to the land of his nativity, it seems only to have
rivetted it more firmly. His imagination, thus influenced, acquired an
undue predominance over his judgment. He viewed the most trifling
occurrences as supernatural indications; and in those azure moments when
the clouds broke from his mind, and when he displayed his usual wit and
pleasantry, he frequently turned the conversation to the subject of his
latter end.

This state of mind was the forerunner, though probably the effect, of a
painful disease, which had, doubtless, its origin in the severity and
continuity of his studies. On the 13th October, when he was supping at
the house of a nobleman called Rosenberg, he was seized with a retention
of urine, which forced him to leave the party.

This attack continued with little intermission for more than a week,
and, during this period, he suffered great pain, attended with want of
sleep and temporary delirium, during which, he frequently exclaimed, _Ne
frustra vixisse videor_. On the 24th he recovered from this painful
situation, and became perfectly tranquil. His strength, however, was
gone, and he saw that he had not many hours to live. He expressed an
anxious wish that his labours would redound to the glory of his Maker,
to whom he offered up the most ardent prayers. He enjoined his sons and
his son-in-law not to allow them to be lost. He encouraged his pupils
not to abandon their pursuits, he requested Kepler to complete the
Rudolphine Tables, and to his family he recommended piety and
resignation to the Divine will. Among those who never quitted Tycho in
his illness, was Erick Brahe, Count Wittehorn, a Swede, and a relation
of his own, and Counsellor to the King of Poland. This amiable
individual never left the bedside of his friend, and administered to him
all those attentions which his situation required. Tycho, turning to
him, thanked him for his affectionate kindness, and requested him to
maintain the relationship with his family. He then expired without pain,
amid the consolations, the prayers, and the tears of his friends. This
event took place on the 24th of October 1601, when he was only
fifty-four years and ten months old.

The Emperor Rudolph evinced the greatest sorrow when he was informed of
the death of his friend, and he gave orders that he should be buried in
the most honourable manner, in the principal church of the ancient
city.[41] The funeral took place on the 4th November, and he was
interred in the dress of a nobleman, and with the ceremonies of his
order. The funeral oration was pronounced by Jessenius, before a
distinguished assemblage, and many elegies were written on his death.

     [41] The church of Tiers, where a monument has been erected to his
     memory.

Tycho was a little above the middle size, and in the last years of his
life he was slightly corpulent. He had reddish yellow hair and a ruddy
complexion. He was of a sanguine temperament, and is said to have been
sometimes irritable, and even obstinate. This failing, however, if he
did possess it, was not exhibited towards his pupils or his scientific
friends, who ever entertained for him the warmest affection and esteem.
Some of his pupils had remained in his house more than twenty years;
and in the quarrel which arose between him and Kepler,[42] and which is
allowed to have originated entirely in the temper of the latter, he
conducted himself with the greatest patience and forbearance. There is
reason to think that the irritability with which he has been charged was
less an affection of his mind than the effect of that noble independence
of character which belonged to him, and that it has been inferred
chiefly from his conduct to some of those high personages with whom he
was brought in contact. When Walchendorp, the President of the Council,
kicked his favourite hound, it was no proof of irritability of character
that Tycho expressed in strong terms his disapprobation of the deed.

     [42] See the Life of Kepler.

It was, doubtless, a greater weakness in his character that he indulged
his turn for satire, without being able to bear retaliation. His jocular
habits, too, sometimes led him into disagreeable positions. When the
Duke of Brunswick was dining with him at Uraniburg, the Duke said,
towards the end of the dinner, that, as it was late, he must be going.
Tycho jocularly remarked that this could not be done without his
permission; upon which the Duke rose and left the party, without taking
leave of his host. Tycho became indignant in his turn, and continued to
sit at table; but, as if repenting of what he had done, he followed the
Duke, who was on his way to the ship, and, calling upon him, displayed
the cup in his hand, as if he had washed out his offence by a draught of
wine.

Tycho was a man of true piety, and cherished the deepest veneration for
the Sacred Scriptures, and for the great truths which they reveal. Their
principles regulated his conduct, and their promises animated his hopes.
His familiarity with the wonders of the heavens increased, instead of
diminishing, his admiration of Divine wisdom, and his daily conversation
was elevated by a constant reference to a superintending Providence.

As a practical astronomer, Tycho has not been surpassed by any observer
of ancient or of modern times. The splendour and number of his
instruments, the ingenuity which he exhibited in inventing new ones and
in improving and adding to those which were formerly known, and his
skill and assiduity as an observer, have given a character to his
labours, and a value to his observations, which will be appreciated to
the latest posterity. The appearance of the new star in 1572 led him to
form a catalogue of 777 stars, vastly superior in accuracy to those of
Hipparchus and Ulugh Beig. His improvements on the lunar theory were
still more valuable. He discovered the important inequality called the
_variation_, and also the annual inequality which depends on the
position of the earth in its orbit. He discovered, also, the inequality
in the inclination of the moon's orbit, and in the motion of her nodes.
He determined with new accuracy the astronomical refractions from an
altitude of 45° down to the horizon, where he found it to be 34´; and he
made a vast collection of observations on the planets, which formed the
groundwork of Kepler's discoveries and the basis of the Rudolphine
Tables. Tycho's powers of observation were not equalled by his capacity
for general views. It was, perhaps, owing more to his veneration for the
Scriptures than to the vanity of giving his name to a new system that he
rejected the Copernican hypothesis. Hence he was led to propose a new
system, called the Tychonic, in which the earth is stationary in the
centre of the universe, while the sun, with all the other planets and
comets revolving round him, performs his daily revolution about the
earth. This arrangement of the planets afforded a sufficient explanation
of the various phenomena of the heavens; and as it was consistent with
the language of Scripture, and conformable to the indications of the
senses, it found many supporters, notwithstanding the physical absurdity
of making the whole system revolve round one of the smallest of the
planets.

It is a painful transition to pass from the astronomical labours of
Tycho to his astrological and chemical pursuits. That Tycho studied and
practised astrology has been universally admitted. He calculated the
nativity of the Emperor Rudolph, and foretold that his relations would
make some attempts upon his life. The credulous Emperor confided in the
prediction, and when the conduct of his brother seemed to justify his
belief, he confined himself to his palace, and fell a prey to the fear
which it inspired. Tycho, however, seems to have entirely renounced his
astrological faith in his latter days; and Kepler states,[43] in the
most pointed manner, that Tycho carried on his astronomical labours with
his mind entirely free from the superstitions of astrology; that he
derided and detested the vanity and knavery of astrologers, and was
convinced that the stars exercised no influence on the destinies of men.

     [43] In his Preface to the Rudolphine Tables.

Although Tycho informed Rothman that he devoted as much labour and
expense to the study of terrestrial (chemistry) as he did to that of
celestial astronomy, yet it is a singular fact that he never published
any account of his experiments, nor has he left among his writings any
trace of his chemical inquiries. He pretended, however, to have made
discoveries in the science, and we should have been disposed to
reprobate the apology which he makes for not publishing them, did we not
know that it had been frequently given by the other alchemists of the
age--"On consideration," says he, "and by the advice of the most learned
men, I thought it improper to unfold the secrets of the art (of alchemy)
to the vulgar, as few persons were capable of using its mysteries to
advantage and without detriment."

Admitting then, as we must do, that Tycho was not only a professed
alchemist, but that he was practically occupied with its pursuits, and
continually misled by its delusions, it may not be uninteresting to the
reader to consider how far a belief in alchemy, and a practice of its
arts, have a foundation in the weakness of human nature; and to what
extent they are compatible with the piety and elevated moral feeling by
which our author was distinguished.

In the history of human errors two classes of impostors, of very
different characters, present themselves to our notice--those who
wilfully deluded their species, and those who permitted their species to
delude themselves. The first of those classes consisted of the selfish
tyrants who upheld an unjust supremacy by systematic delusions, and of
grovelling mountebanks who quenched their avaricious thirst at the
fountains of credulity and ignorance. The second class comprehended
spirits of a nobler mould: It embraced the speculative enthusiasts, whom
the love of fame and of truth urged onward, in a fruitless research,
and those great lights of knowledge and of virtue, who, while they stood
forward as the landmarks of the age which they adorned, had neither the
intellectual nor the moral courage to divest themselves of the
supernatural radiance with which the ignorance of the vulgar had
encircled them.

The thrones and shrines, which delusion once sustained even in the
civilized quarter of the globe, are for ever fallen, and that civil and
religious liberty, which in past ages was kept down by the marvellous
exhibitions of science to the senses, is now maintained by its
application to the reason of man. The charlatans, whether they deal in
moral or in physical wonders, form a race which is never extinct. They
migrate to the different zones of the social system, and though they
change their place, and their purposes, and their victims, yet their
character and motives remain the same. The philosophical mind,
therefore, is not disposed to study either of these varieties of
impostors; but the other two families which compose the second class are
objects of paramount interest. The eccentricities and even the
obliquities of great minds merit the scrutiny of the metaphysician and
the moralist, and they derive a peculiar interest from the state of
society in which they are exhibited. Had Cardan and Cornelius Agrippa
lived in modern times, their vanity and self-importance would have been
checked by the forms of society, and even if their harmless pretensions
had been displayed, they would have disappeared in the blaze of their
genius and knowledge. But nursed in superstition, and educated in dark
and turbulent times, when every thing intellectual was in a state of
restless transition, the genius and character of great men necessarily
reflected the peculiarities of the age in which they lived.

Had history transmitted to us correct details of the leading alchemists
and scientific magicians of the dark ages, we should have been able to
analyse their actions and their opinions, and trace them, probably, to
the ordinary principles by which the human mind is in every age
influenced and directed. But when a great man has once become an object
either of interest or of wonder, and still more when he is considered as
the possessor of knowledge and skill which transcend the capacity of the
age, he is soon transformed into the hero of romance. His powers are
overrated, his deeds exaggerated, and he becomes the subject of idle
legends, which acquire a firmer hold on credulity from the slight
sprinkling of truth with which they are seasoned. To disclaim the
possession of lofty attributes thus ascribed to great men is a degree of
humility which is not often exercised. But even when this species of
modesty is displayed, it never fails to defeat its object. It but calls
forth a deeper homage, and fixes the demigod more firmly in his shrine.

The history of learning furnishes us with many examples of that species
of delusion in which a great mind submits itself to vulgar adulation,
and renounces unwillingly, if it renounces at all, the unenviable
reputation of supernatural agency. In cases where self-interest and
ambition are the basis of this peculiarity of temperament, and in an age
when the conjuror and the alchemist were the companions and even the
idols of princes, it is easy to trace the steps by which a gifted sage
retains his ascendancy among the ignorant. The hecatomb which is
sacrificed to the magician, he receives as an oblation to his science,
and conscious of possessing real endowments, the idol devours the meats
that are offered to him without analysing the motives and expectations
under which he is fed. But even when the idolater and his god are not
placed in this transverse relation, the love of power or of notoriety is
sufficient to induce good men to lend a too willing ear to vulgar
testimony in favour of themselves; and in our own times it is not common
to repudiate the unmerited cheers of a popular assembly, or to offer a
contradiction to fictitious tales which record our talents or our
courage, our charity or our piety.

The conduct of the scientific alchemists of the thirteenth, fourteenth,
and fifteenth centuries presents a problem of very difficult solution.
When we consider that a gas, a fluid, and a solid may consist of the
very same ingredients in different proportions; that a virulent poison
may differ from the most wholesome food only in the difference of
quantity of the very same elements; that gold and silver, and lead and
mercury, and indeed all the metals, may be extracted from transparent
crystals, which scarcely differ in their appearance from a piece of
common salt or a bit of sugarcandy; and that diamond is nothing more
than charcoal,--we need not greatly wonder at the extravagant
expectation that the precious metals and the noblest gems might be
procured from the basest materials. These expectations, too, must have
been often excited by the startling results of their daily experiments.
The most ignorant compounder of simples could not fail to witness the
magical transformations of chemical action; and every new product must
have added to the probability that the tempting doublets of gold and
silver might be thrown from the dice-box with which he was gambling.

But when the precious metals were found in lead and copper by the action
of powerful re-agents, it was natural to suppose that they had been
actually formed during the process; and men of well-regulated minds even
might have thus been led to embark in new adventures to procure a more
copious supply, without any insult being offered to sober reason, or any
injury inflicted on sound morality.

When an ardent and ambitious mind is once dazzled with the fascination
of some lofty pursuit, where gold is the object, or fame the impulse, it
is difficult to pause in a doubtful career, and to make a voluntary
shipwreck of the reputation which has been staked. Hope still cheers
the aspirant from failure to failure, till the loss of fortune and the
decay of credit disturb the serenity of his mind, and hurry him on to
the last resource of baffled ingenuity and disappointed ambition. The
philosopher thus becomes an impostor; and by the pretended transmutation
of the baser metals into gold, or the discovery of the philosopher's
stone, he attempts to sustain his sinking reputation, and recover the
fortune he has lost. The communication of the great secret is now the
staple commodity with which he is to barter, and the grand talisman with
which he is to conjure. It can be imparted only to a chosen few--to
those among the opulent who merit it by their virtues, and can acquire
it by their diligence, and the divine vengeance is threatened against
its disclosure. A process commencing in fraud and terminating in
mysticism is conveyed to the wealthy aspirant, or instilled into the
young enthusiast, and the grand mystery passes current for a season,
till some cautious professor of the art, like Tycho, denounces its
publication as detrimental to society.

Among the extravagant pretensions of the alchemists, that of forming a
universal medicine was perhaps not the most irrational. It was only when
they pretended to cure every disease, and to confer longevity, that they
did violence to reason. The success of the Arabian physicians in the use
of mercurial preparations naturally led to the belief that other
medicines, still more general in their application, and efficacious in
their healing powers, might yet be brought to light; and we have no
doubt that many substantial discoveries were the result of such
overstrained expectations. Tycho was not merely a believer in the
medical dogmas of the alchemists, he was actually the discoverer of a
new _elixir_, which went by his name, and which was sold in every
apothecary's shop as a specific against the epidemic diseases which were
then ravaging Germany. The Emperor Rudolph having heard of this
celebrated medicine, obtained a small portion of it from Tycho by the
hands of the Governor of Brandisium; but, not satisfied with the gift,
he seems to have applied to Tycho for an account of the method of
preparing it. Tycho accordingly addressed to the Emperor a long letter,
dated September 7, 1599, containing a minute account of the process.
The base of this remarkable medicine is Venetian treacle, which
undergoes an infinity of chemical operations and admixtures before it is
ready for the patient. When properly prepared he assures the Emperor
that it is better than gold, and that it may be made still more valuable
by mixing with it a single scruple either of the tincture of corals, or
sapphire, or hyacinth, or a solution of pearls, or of potable gold, if
it can be obtained free of all corrosive matter! In order to render the
medicine _universal_ for all diseases which can be cured by
perspiration, and which, he says, form a third of those which attack the
human frame, he combines it with antimony, a well known sudorific in the
present practice of physic. Tycho concludes his letter by humbly
beseeching the Emperor to keep the process secret, and reserve the
medicine for himself alone!

The same disposition of mind which made Tycho an astrologer and an
alchemist, inspired him with a singular love of the marvellous.

He had various automata with which he delighted to astonish the
peasants; and by means of invisible bells, which communicated with every
part of his establishment, and which rung with the gentlest touch, he
had great pleasure in bringing any of his pupils suddenly before
strangers, muttering at a particular time the words "Come hither,
Peter," as if he had commanded their presence by some supernatural
agency. If, on leaving home, he met with an old woman or a hare, he
returned immediately to his house: But the most extraordinary of all his
peculiarities remains to be noticed. When he lived at Uraniburg he
maintained an idiot of the name of Lep, who lay at his feet whenever he
sat down to dinner, and whom he fed with his own hand. Persuaded that
his mind, when moved, was capable of foretelling future events, Tycho
carefully marked every thing he said. Lest it should be supposed that
this was done to no purpose, Longomontanus relates that when any person
in the island was sick, Lep never, when interrogated, failed to predict
whether the patient would live or die. It is stated also in the letters
of Wormius, both to Gassendi and Peyter, that when Tycho was absent, and
his pupils became very noisy and merry in consequence of not expecting
him soon home, the idiot, who was present, exclaimed, _Juncher xaa
laudit_, "Your master has arrived." On another occasion, when Tycho had
sent two of his pupils to Copenhagen on business, and had fixed the day
of their return, Lep surprised him on that day while he was at dinner,
by exclaiming, "Behold your pupils are bathing in the sea." Tycho,
suspecting that they were shipwrecked, sent some person to the
observatory to look for their boat. The messenger brought back word that
he saw some persons wet on the shore, and in distress, with a boat upset
at a great distance. These stories have been given by Gassendi, and may
be viewed as specimens of the superstition of the age.

Tycho left behind him a wife and six children, but even in the time of
Gassendi nothing was known of their history, excepting that Tengnagel,
who married one of the daughters, gave up his scientific pursuits, and,
having been admitted among the Emperor's counsellors, was employed in
several of his embassies.

The instruments of Tycho were purchased from his heirs, by the Emperor,
for 22,000 crowns. They were shut up in the house of Curtius, and were
treated with such veneration, that no astronomer, not even Kepler
himself, was permitted to see or to use them.

Here they remained till the death of the Emperor Matthias, in 1619, when
the troubles in Bohemia took place. When Prague was taken by the forces
of the Elector Palatine, the instruments were carried off, and some were
destroyed, and others converted to different purposes. The great brass
globe, however, was saved. It was first carried to Niessa, the episcopal
city of Silesia; and having been presented to the College of Jesuits, it
was preserved in their museum, till Udalric, the son of Christian, King
of Denmark, took Niessa in 1632. The globe was recognized as having
belonged to Tycho, and it was carried in triumph to Denmark. An
inscription was written upon it by Longomontanus, and it was deposited
with some pomp in the Library of the Academy of Sciences.

After Tycho left Huen, the island was transferred to some of the Danish
nobility, and the following brief but melancholy description of it was
given by Wormius. "There is, in the island, a field where Uraniburg
was." The scientific antiquities of Huen, have been more recently
described by Mr Cox, in his travels through Denmark.

"We landed," says he, "on the south west part in a small bay, just
below the place where a stream, supplied by numerous pools and fish
ponds, falls into the sea. We ascended the shore, which is clothed with
short herbage, crossed the stream, and passed over a gently waving
surface, gradually sloping towards the sea, and walked a mile to a farm
house, standing in the middle of the island, inhabited by Mr Schaw, a
Swedish gentleman, to whom the greater part of the island belongs. He
lives here in summer, but in winter resides at Landscrona. This dwelling
is the same as existed in Tycho Brahe's time, and was the farm house
belonging to his estate. A guide, whom we obtained from Mr Schaw,
conducted us to the remains of Tycho's mansion, which are near the
house, and consist of little more than a mound of earth which enclosed
the garden, and two pits, the sites of his mansion and observatory."[44]

     [44] Cox's Travels in Poland, &c., vol. v., p. 189, 190.




LIFE OF JOHN KEPLER.




CHAPTER I.

     _Kepler's Birth in 1571--His Family--And early Education--The
     Distresses and Poverty of his Family--He enters the Monastic School
     of Maulbronn--And is admitted into the University of Tubingen,
     where he distinguishes himself, and takes his Degrees--He is
     appointed Professor of Astronomy and Greek in 1594--His first
     speculations on the Orbits of the Planets--Account of their
     Progress and Failure--His "Cosmographical Mystery" published--He
     Marries a Widow in 1597--Religious troubles at Gratz--He retires
     from thence to Hungary--Visits Tycho at Prague in 1600--Returns to
     Gratz, which he again quits for Prague--He is taken Ill on the
     road--Is appointed Tycho's Assistant in 1601--Succeeds Tycho as
     Imperial Mathematician--His Work on the New Star of 1604--Singular
     specimen of it._


It is a remarkable circumstance in the history of science, that
astronomy should have been cultivated at the same time by three such
distinguished men as Tycho, Kepler, and Galileo. While Tycho, in the
54th year of his age, was observing the heavens at Prague, Kepler, only
30 years old, was applying his wild genius to the determination of the
orbit of Mars, and Galileo, at the age of 36, was about to direct the
telescope to the unexplored regions of space. The diversity of gifts
which Providence assigned to these three philosophers was no less
remarkable. Tycho was destined to lay the foundation of modern
astronomy, by a vast series of accurate observations made with the
largest and the finest instruments; it was the proud lot of Kepler to
deduce the laws of the planetary orbits from the observations of his
predecessors; while Galileo enjoyed the more dazzling honour of
discovering by the telescope new celestial bodies, and new systems of
worlds.

John Kepler, the youngest of this illustrious band, was born at the
imperial city of Weil, in the duchy of Wirtemberg, on the 21st December
1571. His parents, Henry Kepler and Catherine Guldenmann, were both of
noble family, but had been reduced to indigence by their own bad
conduct. Henry Kepler had been long in the service of the Duke of
Wirtemberg as a petty officer, and in that capacity had wasted his
fortune. Upon setting out for the army, he left his wife in a state of
pregnancy; and, at the end of seven months, she gave premature birth to
John Kepler, who was, from this cause, a sickly child during the first
years of his life. Being obliged to join the army in the Netherlands,
his wife followed him into the field, and left her son, then five years
old, under the charge of his grandfather at Limberg. Sometime afterwards
he was attacked with the smallpox, and having with difficulty recovered
from this severe malady, he was sent to school in 1577.

Having become security for one of his friends, who absconded from his
creditors, Henry Kepler was obliged to sell his house and all his
property, and was driven to the necessity of keeping a tavern at
Elmendingen. Owing to these misfortunes, young Kepler was taken from
school about two years afterwards, and was obliged to perform the
functions of a servant in his father's house. In 1585, he was again
placed in the school of Elmendingen; but his father and mother having
been both attacked with the smallpox, and he himself having been seized
with a violent illness in 1585, his education had been much neglected,
and he was prohibited from all mental application.

In the year 1586, on the 26th of November, Kepler was admitted into the
school at the Monastery of Maulbronn, which had been established at the
Reformation, and which was maintained at the expense of the Duke of
Wirtemberg, as a preparatory seminary for the University of Tubingen.
After remaining a year at the upper classes, the scholars presented
themselves for examination at the College for the degree of Bachelor;
and having received this, they returned to the school with the title of
Veterans. Here they completed the usual course of study; and being
admitted as resident students at Tubingen, they took their degree of
Master. In prosecuting this course of study, Kepler was sadly
interrupted, not only by periodical returns of his former complaints,
but by family quarrels of the most serious import. These dissensions,
arising greatly from the perverseness of his mother, drove his father to
a foreign land, where he soon died; and his mother having quarrelled
with all her relations, the affairs of the family were involved in
inextricable disorder. Notwithstanding these calamities, Kepler took his
degree of Bachelor on the 15th September 1588, and his degree of Master
in August 1591, on which occasion he held the second place at the annual
examination.

In his early studies, Kepler devoted himself with intense pleasure to
philosophy in general, but he entertained no peculiar affection for
astronomy. Being well grounded in arithmetic and geometry, he had no
difficulty in making himself master of the geometrical and astronomical
theorems which occurred in the course of his studies. While attending
the lectures of Moestlin, professor of mathematics, who had
distinguished himself by an oration in favour of the Copernican system,
Kepler not only became a convert to the opinions of his master, but
defended them in the physical disputations of the students, and even
wrote an essay on the primary motion, in order to prove that it was
produced by the daily rotation of the earth.

In 1594, the astronomical chair at Gratz, in Styria, fell vacant by the
death of George Stadt, and, according to Kepler's own statement, he was
forced to accept this situation by the authority of his professional
tutors, who recommended him to the nobles of Styria. Though Kepler had
little knowledge of the science, and no passion for it whatever, yet the
nature of his office forced him to attend to astronomy; and, in the year
1595, when he enjoyed some leisure from his lectures, he directed the
whole energy of his mind to the three important topics of the number,
the size, and the motion of the orbits of the planets. He first tried if
the size of the planets' orbits, or the difference of their sizes, had
any regular proportion to each other. Finding no proof of this, he
inserted a new planet between Mars and Jupiter, and another between
Venus and Mercury, which he supposed might be invisible from their
smallness; but even with these assumptions the distances of the planets
exhibited no regular progression. Kepler next tried if these distances
varied as the cosines of the quadrant, and if their motion varied as
the sun's, the sine of 90 representing the motion at the sun, and the
sine of 0° that at the fixed stars; but in this trial he was also
disappointed.

Having spent the whole summer in these fruitless speculations, and
praying constantly to his Maker for success, he was accidentally drawing
a diagram in his lecture-room, in July 1595, when he observed the
relation between the circle inscribed in a triangle, and that described
round it; and the ratio of these circles, which was that of 1 to 2,
appeared to his eye to be identical with that of Jupiter's and Saturn's
orbits. Hence he was led to compare the orbits of the other planets'
circles described in pentagons and hexagons. As this hypothesis was as
inapplicable to the heavens as its predecessors, Kepler asked himself in
despair, "What have _plane_ figures to do with _solid_ orbits? Solid
bodies ought to be used for solid orbits." On the strength of this
conceit, he supposed that the distances of the planets were regulated by
the sizes of the five regular solids described within one another. "The
Earth is the circle, the measurer of all. Round it describe a
dodecahedron; the circle including this will be Mars. Round Mars
describe a tetrahedron; the circle including this will be Jupiter.
Describe a cube round Jupiter; the circle including this will be Saturn.
Then inscribe in the Earth an icosahedron; the circle described in it
will be Venus. Inscribe an octohedron in Venus; the circle inscribed in
it will be Mercury."

This discovery, as he considered it, harmonized in a very rude way with
the measures of the planetary orbits given by Copernicus; but Kepler was
so enamoured with it, that he ascribed the differences to errors of
observation, and declared that he would not renounce the glory of having
made it for the whole Electorate of Saxony.

In his attempt to discover the relation between the periodic times of
the planets and their distances from the sun, he was not more
successful; but as this relation had a real existence, he made some
slight approach to its determination. These extraordinary researches,
which indicate the wildness and irregularity of Kepler's genius, were
published in 1596, in a work entitled, "Prodromus of Cosmographical
Dissertations; containing the cosmographical mystery respecting the
admirable proportion of the celestial orbits, and the genuine and real
causes of the number, magnitude, and periods of the planets demonstrated
by the five regular geometrical solids."

Notwithstanding the speculative character of this volume, it obtained
for its author a high name among astronomers. Galileo and Tycho, whose
opinions of it he requested, spoke of it with some commendation. The
former praised the ingenuity and good faith which it displayed; and
Tycho, though he requested him to try to adapt something of the same
nature to the Tychonic system, saw the speculative character of his
mind, and advised him "to lay a solid foundation for his views by actual
observation, and then, by ascending from these, to strive to reach the
causes of things."

In 1592, before Kepler had quitted Tubingen, he was on the eve of
entering into the married state. Though the foolish scheme was
fortunately broken off, yet he resumed it again in 1596, when he paid
his addresses to Barbara Millar of Muleckh, who was a widow for the
second time, though only twenty-three years of age. Her parents,
however, would not consent to the match till Kepler proved his
nobility; and, owing to the delay which arose from this circumstance,
the marriage did not take place till 1597. The income which Kepler
derived from his professorship was very small, and as his wife's fortune
turned out much less than he had been led to expect, he not only was
annoyed with pecuniary difficulties, but was involved in disputes with
his wife's relations. These evils were greatly increased by the
religious troubles which took place in Styria. The Catholics at Gratz
rose against the Protestants, and threatened to expell them from the
city. Kepler, who openly professed the Protestant religion, saw the
risks to which he was exposed, and retired with his wife into Hungary.
Here he continued nearly a year, during which he composed and
transmitted to his friend Zehentmaier, at Tubingen, several small
treatises, "On the Magnet," "On the cause of the Obliquity of the
Ecliptic," and "On the Divine Wisdom, as shewn in the Creation"--all of
which seem to have been lost. In 1599, Kepler was recalled to Gratz by
the States of Styria, and resumed his professorship; but the city was
still divided into two factions, and Kepler, who was a lover of peace,
found his situation very uncomfortable. Having learned from Tycho that
he had been able to determine more accurately than had been done the
eccentricities of the orbits of the planets, Kepler was anxious to avail
himself of these observations, and set out on a visit to Tycho at
Prague, where he arrived in January 1600. Tycho received him with great
kindness, notwithstanding the part which he had taken against him along
with Raimar, and he spent three or four months with him at Benach. It
was then arranged that Kepler should be appointed Tycho's assistant in
the observatory, with a salary of 100 florins, provided the States of
Styria should, on the Emperor's application, allow him to be absent for
two years and retain his salary. Kepler had returned to Gratz before
this arrangement was completed, and new troubles having broke out in
that city, he resigned his professorship. Dreading lest this step would
frustrate his scheme of joining Tycho, he resolved to ask the patronage
of the Duke of Wirtemberg for the professorship of medicine at Tubingen;
and with this view he corresponded with Moestlin and his other friends
in that University. When Tycho heard of this plan, he pressed him to
abandon it, and promised his best exertions to procure a permanent
situation for him from the Emperor.

Encouraged by these promises, Kepler and his wife set off for Prague,
but he was unfortunately attacked on the road with a quartan ague, which
lasted seven months; and having exhausted the little money which he had
along with him, he was obliged to apply to Tycho for a supply. After his
arrival at Prague he was supported entirely by the bounty of his friend,
and he endeavoured to make some return for this kindness by attacking in
a controversial pamphlet two of the scientific opponents of Tycho.
Kepler's total dependence on the generosity of his friend had made him
suspicious of his sincerity. He imagined that Tycho had not freely
communicated to him all his observations, and that he had not been
sufficiently liberal in supplying his wife with money in his absence.
While absent a second time from Prague, and influenced by these
feelings, he addressed a violent letter to Tycho, filled with
reproaches. On the plea of being occupied with his daughter's marriage,
Tycho requested Ericksen, one of his assistants, to reply to Kepler's
letter; and he did this with so much effect, that Kepler saw his
mistake, and in the noblest and most generous manner supplicated the
forgiveness of his friend. Tycho exhibited the same good feeling; and
the kindness of Hoffman, President of the States of Styria, completed
the reconciliation of the two astronomers.

On his return to Prague in 1601, he was presented by Tycho to the
Emperor, who conferred upon him the title of Imperial Mathematician, on
the condition that he would assist Tycho in his calculations. This
connexion was peculiarly valuable to Kepler, as the observations of his
colleague were the only ones made in the world which could enable him to
carry on his own theoretical inquiries. These two astronomers now
undertook to compute, from Tycho's observations, a new set of
astronomical tables, to be called the Rudolphine Tables, in honour of
the Emperor. This scheme flattered the vanity of their master, and he
pledged himself to pay all the expenses of the work. Longomontanus,
Tycho's principal assistant, took upon himself the labour of arranging
and discussing the observations on the stars, while Kepler devoted
himself to the more congenial task of examining those on the planet
Mars, with which Tycho was at that time particularly occupied. The
appointment of Longomontanus to a professorship in Denmark, and the
death of Tycho in October 1601, put a stop to these important schemes.

Kepler succeeded Tycho as principal mathematician to the Emperor, and
was provided with a handsome salary, which was partly charged on the
imperial treasury, and partly on the States of Silesia, and the first
instalment of which was to be paid in March 1602. The generosity of the
Emperor did not fail to excite the jealousy of ignorant individuals, who
were not aware of the value of science to the state; but the increasing
fame of Kepler, and the valuable works which he published, soon silenced
their opposition.

In September 1604, astronomers were surprised with the appearance of a
new star in the foot of Serpentarius. It was not seen before the 29th of
September, and Moestlin informs us that, on account of clouds, he did
not obtain a good view of it till the 6th of October. Like that of
1572,[45] it at first surpassed Jupiter in brightness, and rivalled even
Venus, but it afterwards became as small as Regulus, and as dull as
Saturn, and disappeared at the end of a few months. It constantly
changed its colour, and was at first tawny, then yellow, then purple and
red, and often white at great altitudes. It had no parallax, and
therefore was a fixed star. Kepler wrote a short account of this
remarkable body, and maintained its superiority to that of 1572, as this
last came in an ordinary year, while the other appeared in the year of
the _fiery trigon_, or that in which Saturn, Jupiter, and Mars, are in
the three fiery signs, Aries, Leo, and Sagittarius, an event which
occurs only every 800 years. After discussing a great variety of topics,
but little connected with his subject, and in a style of absurd
jocularity, he attacks the opinions of the Epicureans, that the star was
a fortuitous concourse of atoms, in the following remarkable paragraph,
which is a good specimen of the work:--"When I was a youth with plenty
of idle time on my hands, I was much taken with the vanity, of which
some grown men are not ashamed, of making anagrams by transposing the
letters of my name, written in Latin. Out of _Joannes Keplerus_ came
_Serpens in Akuleo_ (a serpent in his sting); but not being satisfied
with the meaning of these words, and being unable to make another, I
trusted the thing to chance, and taking out of a pack of playing cards
as many as there were letters in the name, I wrote one upon each, and
then began to shuffle them, and at each shuffle to read them in the
order they came, to see if any meaning came of it. Now, may all the
Epicurean gods and goddesses confound this same chance, which, although
I have spent a good deal of time over it, never shewed me anything like
sense even from a distance. So I gave up my cards to the Epicurean
eternity, to be carried away into infinity; and, it is said, they are
still flying about there in the utmost confusion among the atoms, and
have never yet come to any meaning. I will tell those disputants, my
opponents, not my own opinion, but my wife's. Yesterday, when weary with
writing, and my mind quite dusty with considering these atoms, I was
called to supper, and a salad I had asked for was set before me. 'It
seems then,' said I, aloud, 'that if pewter dishes, leaves of lettuce,
grains of salt, drops of water, vinegar, and oil, and slices of egg, had
been flying about in the air from all eternity, it might at last happen
by chance that there would come a salad.' 'Yes,' says my wife, 'but not
so nice and well dressed as this of mine is.'"

     [45] See the Life of Tycho, page 137.




CHAPTER II.

     _Kepler's Pecuniary Embarrassments--His Inquiries respecting the
     Law of Refraction--His Supplement to Vitellio--His Researches on
     Vision--His Treatise on Dioptrics--His Commentaries on Mars--He
     discovers that the orbit of Mars is an Ellipse, with the Sun in one
     focus--And extends this discovery to all the other Planets--He
     establishes the two first laws of Physical Astronomy--His Family
     Distresses--Death of his Wife--He is appointed Professor of
     Mathematics at Linz--His Method of Choosing a Second Wife--Her
     Character, as given by Himself--Origin of his Treatise on
     Gauging--He goes to Ratisbon to give his Opinion to the Diet on the
     change of Style--He refuses the Mathematical Chair at Bologna._


Although Kepler now filled one of the most honourable situations to
which a philosopher could aspire, and possessed a large salary fitted to
supply his most reasonable wants, yet, as the imperial treasury was
drained by the demands of an expensive war, his salary was always in
arrear. Owing to this cause he was constantly involved in pecuniary
difficulties, and, as he himself described his situation, he was
perpetually begging his bread from the Emperor at Prague. His increasing
family rendered the want of money still more distressing, and he was
driven to the painful alternative of drawing his income from casting
nativities. From the same cause he was obliged to abandon his plan of
publishing the Rudolphine Tables, and to devote himself to works of a
less expensive kind, and which were more likely to yield some pecuniary
advantages.

In spite of these embarrassments, and the occupation of his time in the
practice of astrology, Kepler found leisure for his favourite pursuits.
No adverse circumstances were capable of extinguishing his scientific
ardour, and whenever he directed his vigorous mind to the investigation
of phenomena, he never failed to obtain interesting and original
results. Since the death of Tycho, his attention had been much occupied
with the subject of refraction and vision; and, in 1606, he published
the result of his researches in a work, entitled "A Supplement to
Vitellio, in which the optical part of astronomy is treated, but
chiefly on the artificial observation and estimation of diameters, and
of the eclipses of the Sun and Moon." Astronomers had long been
perplexed with the refraction of the atmosphere, and so little was known
of the general subject, as well as of this branch of it, that Tycho
believed the refraction of the atmosphere to cease at 45° of altitude.
Even at the beginning of the second century, Claudius Ptolemy of
Alexandria had unravelled its principal mysteries, and had given in his
Optics a theory of astronomical refraction more complete than that of
any astronomer before the time of Cassini;[46] but the MSS. had
unfortunately been mislaid, and Alhazen and Vitellio and Kepler were
obliged to take up the subject from its commencement. Ptolemy had not
only determined that the refraction of the atmosphere had gradually
increased from the zenith to the horizon, but he had measured with
singular accuracy the angles of refraction for water and glass, from a
perpendicular incidence to a horizontal one.

     [46] Cassini was born in 1625, and died in 1712.

Kepler treated this branch of science in his own peculiar way,
"hunting down," as he expressed it, every hypothesis which his fertile
imagination had successively presented to him. In his various attempts
to discover the law of refraction, or a measure of it, as varying with
the density of the body and the angle of incidence of the light, he was
nearer the goal, in his first speculation, than in any of the rest; and
he seems to have failed in consequence of his not separating the
question as it related to density from the question as it related to
incidence. "I did not leave untried," says he, "whether, by assuming a
horizontal refraction according to the density of the medium, the rest
would correspond to the sines of the distances from a vertical
direction, but calculation proved that it was not so: and, indeed, there
was no occasion to have tried it, for thus the _refraction would
increase according to the same law in all mediums, which is contradicted
by experiment_."

Although completely foiled in his search after the law of refraction,
which was subsequently discovered by Willebrord Snell, and sometime
afterwards by James Gregory, he was, singularly successful in his
inquiries respecting vision. Regarding the eye as analogous in its
structure with the camera obscura of Baptista Porta, he discovered that
the images of external objects were painted in an inverted position on
the retina, by the union of the pencils of rays which issued from every
point of the object. He ascribed an erect vision to an operation of the
mind, by which it traces the rays back to the pupil, where they cross
one another, and thus refers the lower parts of the image to the higher
parts of the object. He also explained the cause of long-sighted and
short-sighted vision, and shewed how convex and concave lenses enabled
those who possessed these peculiarities of vision to see distinctly, by
accurately converging the pencils of rays to a focus on the retina.
Kepler likewise observed the power of accommodating the eye to different
distances, and he ascribed it to the contraction of the ciliary
processes, which drew the sides of the eyeball towards the crystalline
lens, and thus elongated the eye so as to produce an adjustment of it
for near objects. Kepler wisely declined to inquire into the way in
which the mind perceives the images painted on the retina, and he
blames Vitellio for attempting to determine a question which he
considered as not belonging to optics.

The work of Kepler, now under consideration, contains the method of
calculating eclipses which is now in use at the present day.

The only other optical treatise written by Kepler, was his _Dioptrics_,
with an appendix on the use of optics in philosophy. This admirable
work, which laid the foundation of the science, was published at
Augsburg in 1611, and reprinted at London in 1653. Although Maurolycus
had made some slight progress in studying the passage of light through
different media, yet it is to Kepler that we owe the methods of tracing
the progress of rays through transparent bodies with convex and concave
surfaces, and of determining the foci of lenses, and of the relative
positions of the images which they form, and the objects from which the
rays proceed. He was thus led to explain the _rationale_ of the
telescope, and to invent the astronomical telescope, which consists of
two convex lenses, by which objects are seen inverted. Kepler also
discovered the important fact, that spherical surfaces were not capable
of converging rays to a single focus, and he conjectured, what
Descartes afterwards proved, that this property might be possessed by
lenses having the figure of some of the sections of the cone. The total
reflection of light at the second surface of bodies was likewise studied
by Kepler, and he determined that the total reflection commenced when
the angle of incidence was equal to the angle of refraction, which
corresponded to an incidence of 90.

Two years before the publication of his Dioptrics, viz. in 1609, Kepler
had given to the world his great work, entitled "The New Astronomy, or
Commentaries on the Motions of Mars." The discoveries which this volume
records form the basis of physical astronomy. The inquiries by which he
was led to them began in that memorable year 1601, when he became the
colleague or assistant of Tycho. The powers of original genius were then
for the first time associated with inventive skill and patient
observation; and though the astronomical data provided by Tycho were
sure of finding their application in some future age, yet without them
Kepler's speculations would have been vain, and the laws which they
enabled him to determine would have adorned the history of another
century. Having tried in vain to represent the motion of Mars by an
uniform motion in a circular orbit, and by the cycles and epicycles with
which Copernicus had endeavoured to explain the planetary inequalities,
Kepler was led, after many fruitless speculations,[47] to suppose the
orbit of the planet to be oval; and, from his knowledge of the conic
sections, he afterwards determined it to be an ellipse, with the sun
placed in one of its foci. He then ascertained the dimensions of the
orbit; and, by a comparison of the times employed by the planet to
complete a whole revolution or any part of one, he discovered that the
time in which Mars describes any arches of his elliptic orbit, were
always to one another as the areas contained by lines drawn from the
focus or the centre of the sun to the extremities of the respective
arches; or, in other words, that the radius vector, or the line joining
the Sun and Mars described equal areas in equal times. By examining the
inequalities of the other planets he found that they all moved in
elliptic orbits, and that the radius vector of each described areas
proportional to the times. These two great results are known by the name
of the first and second laws of Kepler. The third law, or that which
relates to the connexion between the periodic times and the distances of
the planets, was not discovered till a later period of his life.

     [47] An interesting account of the steps by which Kepler proceeded
     will be found in Mr Drinkwater Bethune's admirable Life of Kepler,
     in the Library of Useful Knowledge.

When Kepler presented to Rudolph the volume which contained these fine
discoveries, he reminded him jocularly of his requiring the sinews of
war to make similar attacks upon the other planets. The Emperor,
however, had more formidable enemies than Jupiter and Saturn, and from
the treasury, which war had exhausted, he found it difficult to supply
the wants of science. While Kepler was thus involved in the miseries of
poverty, misfortunes of every kind filled up the cup of his adversity.
His wife, who had long been the victim of low spirits, was seized,
towards the end of 1610, with fever, epilepsy, and phrenitis, and before
she had completely recovered, all his three children were simultaneously
attacked with the smallpox. His favourite son fell a victim to this
malady, and at the same time Prague was partially occupied by the troops
of Leopold. The part of the city where Kepler resided was harassed by
the Bohemian levies, and, to crown this list of evils, the Austrian
troops introduced the plague into the city.

Sometime afterwards Kepler set out for Austria with the view of
obtaining the professorship of mathematics at Linz, which was now
vacant; but, upon his return in June, he found his wife in a decline,
brought on by grief for the loss of her son, and she was sometime
afterwards seized with an infectious fever, of which she died.

The Emperor Rudolph was unwilling to allow Kepler to quit Prague. He
encouraged him with hopes that the arrears of his salary would be paid
from Saxony; but these hopes were fallacious, and it was not till the
death of Rudolph, in 1612, that Kepler was freed from these distressing
embarrassments.

On the accession of Mathias, Rudolph's brother, Kepler was re-appointed
imperial mathematician, and was allowed to accept the professorship at
Linz. His family now consisted of two children--a daughter, Susannah,
born in 1602, and a son, Louis, born in 1607. His own time was so
completely occupied by his new professorial duties, as well as by his
private studies, that he found it necessary to seek another parent for
his children. For this purpose, he gave a commission to his friends to
look out for him a suitable wife, and, in a long and jocular letter to
Baron Strahlendorf, he has given an amusing account of the different
negotiations which preceded his marriage. The substance of this letter
is so well given by Mr Drinkwater Bethune, that we shall follow his
account of it.

The first of the eleven ladies among whom his inclinations wavered, "was
a widow, an intimate friend of his first wife; and who, on many
accounts, appeared a most eligible match. At first," says Kepler, "she
seemed favourably inclined to the proposal; it is certain that she took
time to consider it, but at last she very quietly excused herself." It
must have been from a recollection of this lady's good qualities, that
Kepler was induced to make his offer; for we learn rather unexpectedly,
after being informed of her decision, that when he soon afterwards paid
his respects to her, it was the first time that he had seen her during
the last six years; and he found, to his great relief, that "there was
no single pleasing part about her." The truth seems to be, that he was
nettled by her answer, and he is at greater pains than appears
necessary, considering this last discovery, to determine why she would
not accept his offered hand. Among other reasons, he suggested her
children, among whom were two marriageable daughters; and it is
diverting afterwards to find them also in the catalogue, which Kepler
appeared to be making, of all his female acquaintance.... Of the other
ladies, one was too old, another in bad health, another too proud of her
birth and quarterings, a fourth had learned nothing but shewy
accomplishments, "not at all suitable to the sort of life she would have
to lead with me," another grew impatient, and married a more decided
admirer, whilst he was hesitating. "The mischief," says he, "in all
these attachments was, that whilst I was delaying, comparing and
balancing conflicting reasons, every day saw me inflamed with a new
passion." By the time he reached the 8th, he found his match in this
respect. "Fortune at length has avenged herself on my doubtful
inclinations. At first she was quite complying, and her friends also;
presently, whether she did or did not consent, not only I, but she
herself did not know. After the lapse of a few days came a renewed
promise, which, however, had to be confirmed a third time; and four days
after that, she again repeated her confirmation, and begged to be
excused from it. Upon this I gave her up, and this time all my
counsellors were of one opinion." This was the longest courtship in the
list, having lasted three whole months; and, quite disheartened by its
bad success, Kepler's next attempt was of a more timid complexion. His
advances to No. 9 were made by confiding to her the whole story of his
recent disappointment, prudently determining to be guided in his
behaviour, by observing whether the treatment he had experienced met
with a proper degree of sympathy. Apparently the experiment did not
succeed; and, almost reduced to despair, Kepler betook himself to the
advice of a friend, who had for some time past complained that she was
not consulted in this difficult negotiation. When she produced No. 10,
and the first visit was paid, the report upon her was as follows:--"She
has, undoubtedly, a good fortune, is of good family, and of economical
habits: but her physiognomy is most horribly ugly; she would be stared
at in the streets, not to mention the striking disproportion in our
figures. I am lank, lean, and spare; she short and thick: in a family
notorious for fulness, she is considered superfluously fat." The only
objection to No. 11 seems to have been her excessive youth; and when
this treaty was broken off on that account, Kepler turned his back upon
all his advisers, and chose for himself one who had figured as No. 5 in
the list, to whom he professes to have felt attached throughout, but
from whom the representations of his friends had hitherto detained him,
probably on account of her humble station.

The following is Kepler's summary of her character:--"Her name is
Susannah, the daughter of John Reuthinger and Barbara, citizens of the
town of Eferdingen. The father was by trade a cabinetmaker, but both her
parents are dead. She has received an education well worth the largest
dowry, by favour of the Lady of Stahrenberg, the strictness of whose
household is famous throughout the province. Her person and manners are
suitable to mine--no pride, no extravagance. She can bear to work; she
has a tolerable knowledge how to manage a family; middle-aged, and of a
disposition and capability to acquire what she still wants. Her I shall
marry, by favour of the noble Baron of Stahrenberg, at 12 o'clock on the
30th of next October, with all Eferdingen assembled to meet us, and we
shall eat the marriage dinner at Maurice's at the Golden Lion."[48]

     [48] Life of Kepler, chap. vi.

Kepler's marriage seems to have taken place at the time here mentioned;
for, in his book on gauging, published at Linz in 1615, he informs us
that he took home his new wife in November, on which occasion he found
it necessary to stock his cellar with a few casks of wine. When the
wine-merchant came to measure the casks, Kepler objected to his method,
as he made no allowance for the different sizes of the bulging parts of
the cask. From this accident, Kepler was led to study the subject of
gauging, and to write the book which we have mentioned, and which
contains the earliest specimens of the modern analysis.

About this period, Kepler was summoned to the Diet at Ratisbon, to give
his opinion on the reformation of the kalendar, and he published a short
essay on the subject; but though the Government did not scruple to avail
themselves of his services, yet his pension was allowed to fall in
arrear, and, in order to support his family, he was obliged to publish
an Almanac, suited to the taste of the age. "In order," says he, "to
defray the expense of the Ephemeris for two years,[49] I have been
obliged to compose _a vile prophesying Almanac, which is scarcely more
respectable than begging_, unless from its saving the Emperor's credit,
who abandons me entirely, and would suffer me to perish with hunger."

     [49] These Ephemerides, from 1617 to 1620, were published at Linz
     in 1616. The one for 1620 was dedicated to Baron Napier of
     Merchiston.

Although Kepler's residence at Linz was rendered uncomfortable by the
Roman Catholics, who had excommunicated him on account of his refusing
to subscribe to some opinions respecting the ubiquity of our Saviour,
or, as others maintain, on account of some opinions which he had
expressed respecting transubstantiation, yet he refused, in 1617, to
accept of an invitation to fill the mathematical chair at Bologna. The
prospect of his fortune being bettered by such a change could not
reconcile him to live in a country where his freedom of speech and
manners might expose him to suspicion; and he accordingly declined, in
the most respectful manner, the offer which was made him.




CHAPTER III.

     _Kepler's continued Embarrassments--Death of Mathias--Liberality of
     Ferdinand--Kepler's "Harmonies of the World"--The Epitome of the
     Copernican Astronomy--It is prohibited by the Inquisition--Sir
     Henry Wotton, the British Ambassador, invites Kepler to England--He
     declines the Invitation--Neglect of Genius by the English
     Government--Trial of Kepler's Mother--Her final Acquittal--And
     Death at the age of Seventy-five--The States of Styria burn
     publicly Kepler's Calendar--He receives his Arrears of Salary from
     Ferdinand--The Rudolphine Tables published in 1628--He receives a
     Gold Chain from the Grand Dulce of Tuscany--He is Patronised by the
     Duke of Friedland--He removes to Sagan, in Silesia--Is appointed
     Professor of Mathematics at Rostoch--Goes to Ratisbon to receive
     his Arrears--His Death, Funeral, and Epitaph--Monument Erected to
     his Memory in 1803--His Family--His Posthumous Volume, entitled
     "The Dream, or Lunar Astronomy."_


Kepler was kept in a state of constant anxiety from the delay in the
Government to pay up the arrears of his pension, while their repeated
promises prevented him from accepting of other employments. He had hoped
that the affair of the Bolognese chair would rouse the imperial treasury
to a sense of its duty, and enable him to publish the Rudolphine
Tables,--that great work which he owed to the memory both of Tycho and
of Rudolph. But though he was disappointed in this expectation, an event
now occurred which at least held out the prospect of a favourable change
in his circumstances. The Emperor Mathias died in 1619, and was
succeeded by Ferdinand III., who not only continued him in the situation
of his principal mathematician, with his former pension, but promised to
pay up the arrears of it, and to furnish the means for publishing the
Rudolphine Tables.

The year 1619, so favourable to Kepler's prospects in life, was
distinguished also by the publication, at Linz, of one of his most
remarkable productions, entitled "The Harmonies of the World." It is
dedicated to James I. of England, and will be for ever memorable in the
history of science, as containing the celebrated law that the squares of
the periodic times of the planets are to one another as the cubes of
their distances. This singular volume, which is marked with all the
peculiarities which distinguish his Cosmographical Mystery, is divided
into five books. The two first books are principally geometrical, and
relate to regular polygons inscribed in a circle; the third book is a
treatise on music, in which musical proportions are derived from
figures; the fourth book is astrological, and treats of the harmony of
rays emanating on the earth from the heavenly bodies, and on their
influence over the sublunary or human soul; the fifth book is
astronomical and metaphysical, and treats of the exquisite harmonies of
the celestial motions, and of the celebrated third law of the universe,
which we have already referred to.

This law, as he himself informs us, first entered his mind on the 8th
March 1618; but, having made an erroneous calculation, he was obliged to
reject it. He resumed the subject on the 15th May; and having discovered
his former error, he recognised with transport the absolute truth of a
principle which for seventeen years had been the object of his incessant
labours. The delight which this grand discovery gave him had no bounds.
"Nothing holds me," says he; "I will indulge in my sacred fury; I will
triumph over mankind by the honest confession, that I have stolen the
golden vases of the Egyptians, to build up a tabernacle for my God, far
away from the confines of Egypt. If you forgive me, I rejoice; if you
are angry, I can bear it. The die is cast; the book is written, to be
read either now or by posterity, I care not which. It may well wait a
century for a reader, as God has waited six thousand years for an
observer."

About the same time, in 1618, Kepler published, at Linz, the _three_
first books of his "Epitome of the Copernican Astronomy," of which the
_fourth_ was published at the same place in 1622, and the _fifth_,
_sixth_, and _seventh_ at Frankfort in the same year. This interesting
work is a kind of summary of all his astronomical views, drawn up in the
form of a dialogue for the perusal of general readers. Immediately after
its publication, it was placed by the Inquisition in the list of
prohibited books; and the moment Kepler learned this from his
correspondent Remus, he was thrown into great alarm, and requested from
him some information respecting the terms and consequences of the
censure which was then pronounced against him. He was afraid that it
might compromise his personal safety if he went to Italy; that he would
be compelled to retract his opinions; that the censure might extend to
Austria; that the sale of his work would be ruined; and that he must
either abandon his country or his opinions.

The reply of his friend Remus calmed his agitated mind, by explaining to
him the true nature of the prohibition; and he concluded his letter with
a piece of seasonable exhortation, "There is no ground for your alarm
either in Italy or in Austria, only keep yourself within bounds, and put
a guard upon your own passions."

In the year 1620, Sir Henry Wotton, the English ambassador at Venice,
paid a visit to Kepler on his way through Germany. It does not appear
whether or not this visit was paid at the desire of James I., to whom
Kepler had dedicated one of his works, but from the nature of the
communication which was made to him by the ambassador, there are strong
reasons to think that this was the case. Sir Henry Wotton urged Kepler
to take up his residence in England, where he could assure him of a
welcome and an honourable reception; but, notwithstanding the pecuniary
difficulties in which he was then involved, he did not accept of the
invitation. In referring to this offer in one of his letters, written a
year after it was made, he thus balances the difficulties of the
question--"The fires of civil war," says he, "are raging in Germany.
Shall I then cross the sea whither Wotton invites me? I, a German, a
lover of firm land, who dread the confinement of an island, who presage
its dangers, and must drag along with me my little wife and flock of
children?" As Kepler seems to have entertained no doubt of his being
well provided for in England, it is the more probable that the British
Sovereign had made him a distinct offer through his ambassador. A
welcome and an honourable reception, in the ordinary sense of these
terms, could not have supplied the wants of a starving astronomer, who
was called upon to renounce a large though an ill-paid salary in his
native land; and Kepler had experienced too deeply the faithlessness of
royal pledges to trust his fortune to so vague an assurance as that
which is implied in the language of the English ambassador. During the
two centuries which have elapsed since this invitation was given to
Kepler, there has been no reign during which the most illustrious
foreigner could hope for pecuniary support, either from the Sovereign or
the Government of England. What English science has never been able to
command for her indigenous talent, was not likely to be proffered to
foreign merit. The generous hearts of individual Englishmen, indeed, are
always open to the claims of intellectual pre-eminence, and ever ready
to welcome the stranger whom it adorns; but through the frozen
life-blood of a British minister such sympathies have seldom vibrated;
and, amid the struggles of faction and the anxieties of personal and
family ambition, he has turned a deaf ear to the demands of genius,
whether she appeared in the humble posture of a suppliant, or in the
prouder attitude of a national benefactor.

If the imperial mathematician, therefore, had no other assurance of a
comfortable home in England than that of Sir Henry Wotton, he acted a
wise part in distrusting it; and we rejoice that the sacred name of
Kepler was thus withheld from the long list of distinguished characters
whom England has starved and dishonoured.

In the year 1620, Kepler was exposed to a severe calamity, which
continued to harass him for some time. His mother, Catherine Kepler, to
whose peculiarities of temper we have already referred, was arrested on
the 5th April, upon a charge of a very serious nature. One of her
friends having some years before suffered a miscarriage, was
subsequently attacked with violent headaches, and Catherine was charged
with having administered poison to her friend. This accusation was
indignantly repelled, and a young doctor of the law, whom she consulted,
advised her to raise an action against her calumniator. From
professional reasons, or probably pecuniary ones, this zealous
practitioner continued to delay the lawsuit for five years. The judge
who tried it happened to be displaced, and was succeeded by another, who
had a personal quarrel with the prosecutor. The defender, who was aware
of this favourable change in her case, became the accuser, and, in July
1620, Catherine Kepler was sent to prison, and condemned to the torture.
The moment this event reached the ears of her son, he quitted Linz, and
arrived in time to save her from punishment. He found that the evidence
upon which she was condemned had no other foundation but her own
intemperate conduct; and, though his interference was successful, yet
she was not finally released from prison till the 4th November 1621.
Convinced of her innocence, this bold woman, now in the 79th year of her
age, raised a new action for damages against her opponent; but her
death, in April 1622, put an end to her own miseries, as well as to the
anxiety of her son. Among the virtues of this singular woman, we must
number that of generosity. Moestlin, the old preceptor of Kepler, had
generously declined any compensation for his instructions. Kepler never
forgot this act of kindness, and, in the midst of his poverty, he found
means to send to Moestlin a handsome silver cup in token of his
gratitude. In acknowledging this gift, Moestlin remarks, "Your mother
had taken it into her head that you owed me 200 florins, and had brought
15 florins and a chandelier towards reducing the debt, which I advised
her to send to you. I asked her to stay to dinner, which she refused.
However, we hanselled your cup, as you know she is of a thirsty
temperament."

In the same year in which his mother was arrested, the States of Styria
ordered all the copies of the Kalendar for 1624 to be publicly burnt.
There does not seem to be any reason for supposing that this insult
proceeded from his old enemies the Catholics. They would, no doubt, take
an active share in carrying it into effect; but it would appear that his
former patrons were affronted at Kepler's giving the precedence in his
title page to the States of Upper Ens, where he then resided, above the
States of Styria.

In 1622, the Emperor Ferdinand, notwithstanding his own pecuniary
difficulties, ordered the whole of Kepler's arrears to be paid, even
those which had been due by Rudolph and Mathias; and so great was his
anxiety to have the Rudolphine Tables published, that he supplied the
means for their immediate completion. New difficulties, however, sprung
up to retard still longer the appearance of this most important work.
The wars of the reformation, which were then agitating the whole of
Germany, interfered with every peaceful pursuit. The library of Kepler
was sealed up by order of the Jesuits, and it was only his position as
imperial mathematician that saved him from personal inconvenience. A
popular insurrection followed in the train of these disasters. The
peasantry blockaded Linz, the place of Kepler's residence, and it was
not till the year 1627, as the title page bears, or 1628, as Kepler
elsewhere states, that these celebrated Tables were given to the world.

The Rudolphine Tables were published at Ulm in one volume folio. These
Tables were calculated by Kepler from the Observations of Tycho, and are
founded on his own great discovery of the ellipticity of the planetary
orbits. The _first_ and _third_ parts of the work contain logarithmic
and other auxiliary tables, for the purpose of facilitating astronomical
calculations. The _second_ part contains tables of the sun, moon, and
planets; and the _fourth_ a catalogue of 1000 stars, as determined by
Tycho. A nautical map is prefixed to some copies of the tables, and the
description of it contains the first notice of the method of determining
the longitude by means of occultations.

A short time after the publication of these tables, the Grand Duke of
Tuscany, instigated no doubt by Galileo, sent Kepler a gold chain in
testimony of his approbation of the great service which he had rendered
to astronomy.

About this time Albert Wallenstein, Duke of Friedland, a great patron of
astrology, and one of the most distinguished men of the age, made the
most munificent offers to Kepler, and invited him to take up his
residence at Sagan in Silesia. The religious dissensions which agitated
Linz, the love of tranquillity which Kepler had so little enjoyed, and
the publication of his great work, induced him to accept of this offer.
He accordingly removed his family from Linz to Ratisbon in 1629, and he
himself set out for Prague, with the double object of presenting the
Rudolphine Tables to the Emperor, and of soliciting his permission to go
into the service of the Duke of Friedland. The Emperor did not hesitate
to grant this request; and would have gladly transferred Kepler's
arrears as well as himself to the charge of a foreign prince. Kepler
accordingly set out with his wife and family for Sagan, where he arrived
in 1629. The Duke Albert treated him with liberality and distinction. He
supplied him with an assistant for his calculations, and also with a
printing press; and, by his influence with the Duke of Mecklenburg, he
obtained for him a professorship in the University of Rostoch.

In this remote situation, Kepler found it extremely difficult to obtain
payment of the imperial pension which he still retained. The arrears had
accumulated to 8000 crowns, and he resolved to go to the Imperial
Assembly at Ratisbon to make a final effort to obtain them. His
attempts, however, were fruitless. The vexation which this occasioned,
and the great fatigue which he had undergone, threw him into a violent
fever, which is said to have been one of cold, and to have been
accompanied with an imposthume in his brain, occasioned by too much
study. This disease baffled the skill of his physicians, and carried him
off on the 5th November, O.S. 1630, in the sixtieth year of his age.

The remains of this great man were interred in St Peter's Churchyard at
Ratisbon, and the following inscription, embodying an epitaph which he
had written for himself, was engraven on his tombstone.

     IN HOC QUIESCIT VIR NOBILISSIMUS, DOCTISSIMUS ET CELEBERRIMUS DOM.
     JOHANNES KEPLERUS, TRIUM IMPERATORUM RUDOLPHI II., MATHIÆ, ET
     FERDINANDI II., PER ANNOS XXX, ANTEA VERO PROCERUM STYRIÆ AB ANNO
     1594 USQUE 1600, POSTEA QUOQUE ASTRIACORUM ORDINUM AB ANNO 1612
     USQUE AD ANNUM 1628, MATHEMATICUS TOTI ORBI CHRISTIANI, PER
     MONUMENTA PUBLICA COGNITUS, AB OMNIBUS DOCTIS, INTER PRINCIPES
     ASTRONOMIÆ NUMERATUS, QUI PROPRIA MANU ASSIGNATUM POST SE RELIQUIT
     TALE EPITAPHIUM.

        Mensus eram coelos, nunc terræ metior umbras:
        Mens coelestis erat, corporis umbra jacet.

     IN CHRISTO PIE OBIIT ANNO SALUTIS 1630, DIE 5 NOVEMBRIS, ÆTATIS SUÆ
     SEXAGESIMO.

This monument was not long preserved. It was destroyed during the wars
which desolated Germany; and no attempt was made till 1786 to mark with
honour the spot which contained such venerable remains. This attempt,
however, failed, and it was not till 1803 that this great duty was paid
to the memory of Kepler, by the Prince Bishop of Constance, who erected
a handsome monumental temple near the place of his interment, and in the
Botanical Garden of the city. The temple is surmounted by a sphere, and
in the centre is a bust of Kepler in Carrara marble.

Kepler left behind him a wife and seven children--two by his first wife,
Susanna and Louis; and three sons and two daughters by his second wife,
viz.--Sebald, Cordelia, Friedman, Hildebert, and Anna Maria. The eldest
of these, Susanna, was married a few months before her father's death to
Jacob Bartschius, his pupil, who was educated as a physician; and his
son Louis died in 1663, while practising medicine at Konigsberg. The
children by his second wife are said to have died young. They were left
in very narrow circumstances; and though 24,000 florins were due to
Kepler by the Emperor, yet only a part of this sum was received by
Susanna, in consequence of her refusing to give up Tycho's Observations
till the debt was paid. Kepler composed a little work entitled "The
Dream of John Kepler, or Lunar Astronomy," the object of which was to
describe the phenomena seen from the moon; but he died while he and
Bartschius were engaged in its publication, and Bartschius having
resumed the task, died also before its completion. Louis Kepler dreaded
to meddle with a work which had proved so fatal to his father and his
brother-in-law, but this superstitious feeling was overcome, and the
work was published at Frankfort in 1636.




CHAPTER IV.

     _Number of Kepler's published Works--His numerous Manuscripts in 22
     folio volumes--Purchased by Hevelius, and afterwards by Hansch--Who
     publishes Kepler's Life and Correspondence at the expense of
     Charles VI.--The History of the rest of his Manuscripts, which are
     deposited in the Library of the Academy of Sciences at St
     Petersburg--General Character of Kepler--His Candour in
     acknowledging his Errors--His Moral and Religious Character--His
     Astrological Writings and Opinions considered--His Character as an
     Astronomer and a Philosopher--The Splendour of his
     Discoveries--Account of his Methods of Investigating Truth._


Although the labours of Kepler were frequently interrupted by severe and
long-continued indisposition, as well as by the pecuniary embarrassments
in which he was constantly involved, yet the ardour and power of his
mind enabled him to surmount all the difficulties of his position. Not
only did he bring to a successful completion the leading inquiries
which he had begun, but he found leisure for composing an immense number
of works more or less connected with the subject of his studies. Between
1594, when he published his Kalendar at Gratz, and 1630, the year of his
death, he published no fewer than _thirty-three_ separate works; and he
left behind him _twenty-two_ volumes of manuscripts, _seven_ of which
contain his epistolary correspondence.

The celebrated astronomer Hevelius, who was a cotemporary of Louis
Kepler, purchased all these manuscripts from Kepler's representatives.
At the death of Hevelius they were bought by M. Gottlieb Hansch, a
zealous mathematician, who was desirous of giving them to the world. For
this purpose he issued a prospectus in 1714 for publishing them by
subscription, in 22 volumes folio; but this plan having failed, he was
introduced to Charles VI., who liberally obtained for him 1000 ducats to
defray the expense of the publication, and an annual pension of 300
florins. With such encouragement, Hansch published in 1718, in one
volume folio, the correspondence of Kepler, entitled "_Epistolæ ad
Joannem Keplerum, insertis ad easdem responsionibus Keplerianis,
quidquid hactenus reperiri potuerunt, opus novum, et cum Jo. Kepleri
vita._"

The expenses of this volume unfortunately exhausted the 1000 ducats
which had been granted by the Emperor, and, instead of being able to
publish the rest of the MSS., Hansch was under the necessity of pledging
them for 828 florins. Under these difficulties he addressed himself in
vain to the celebrated Wolfius, to the Royal Society of London, and to
other bodies that were likely to interest themselves in such a subject.
In 1761, when M. De Murr of Nuremberg was in London, he made great
exertions to obtain the MSS., and Dr Bradley is said to have been on the
eve of purchasing them. The competition probably raised the demands of
the proprietor, in whose hands they continued for many years. In 1773
they were offered for 4000 francs, and sometime afterwards M. De Murr
purchased them for the Imperial Academy of Sciences at St Petersburg, in
whose library they still remain. Euler, Lexell, and Kraft undertook the
task of examining them, and selecting those that were best fitted for
publication, but we believe that no steps have yet been taken for
executing this task, nor are we aware that science would derive any
advantage from its completion.

Although, in drawing his own character, Kepler describes himself as
"troublesome and choleric in politics and domestic matters," yet the
general events of his life indicate a more peaceful disposition than
might have been expected from the peculiarities of his mind and the
ardour of his temperament. On one occasion, indeed, he wrote a violent
and reproachful letter to Tycho, who had given him no just ground of
offence; but the state of Kepler's health at that moment, and the
necessitous circumstances in which he had been placed, present some
palliation of his conduct. But, independent of this apology, his
subsequent conduct was so truly noble as to reconcile even Tycho to his
penitent friend. Kepler quickly saw the error which he committed; he
lamented it with genuine contrition, and was anxious to remove any
unfavourable impression which he might have given of his friend, by the
most public confession of his error, and by the warmest acknowledgments
of the kindness of Tycho.

In his relations with the scientific men of his own times, Kepler
conducted himself with that candour and love of truth which should
always distinguish the philosopher. He was never actuated by any mean
jealousy of his rivals. He never scrupled to acknowledge their high
merits; and when the discoveries made by the telescope established
beyond a doubt the errors of some of Kepler's views, he willingly avowed
his mistake, and never joined in the opposition which was made by many
of his friends to the discoveries of Galileo. A striking example of this
was exhibited in reference to his supposed discovery of Mercury on the
sun's disc. In the year 1607,[50] Kepler observed upon the face of the
sun a dark spot, which he mistook for Mercury; but the day proving
cloudy, he had not the means of determining by subsequent observations
whether or not this opinion was well founded. As spots on the sun were
at that time unknown, Kepler did not hesitate to publish the fact in
1607, in his _Mercurius in Sole visus_; but when Galileo, a few years
afterwards, discovered a great number of similar spots with the
telescope, Kepler retracted his opinions, and acknowledged that
Galileo's discovery afforded an explanation, also, of many similar
observations in old writers, which he had found it difficult to
reconcile with the actual motions of Mercury.

     [50] It is said that Kepler saw this dark spot _while looking at
     the sun in a camera obscura_. As a camera obscura is actually a
     telescope, magnifying objects in proportion to the focal length of
     the lens employed, he may be said to have first seen these spots
     with the aid of an optical instrument.

Kepler was not one of those cold-hearted men who, though continually
occupied in the study of the material world, and ambitious of the
distinction which a successful examination of it confers, are yet
insensible to the goodness and greatness of the Being who made and
sustains it. His mind was cast in a better mould. The magnificence and
harmony of the divine works excited in him not only admiration but love.
He felt his own humility the farther he was allowed to penetrate into
the mysteries of the universe; and sensible of the incompetency of his
unaided powers for such transcendent researches, and recognising himself
as but the instrument which the Almighty employed to make known his
wonders, he never entered upon his inquiries without praying for
assistance from above. This frame of mind was by no means inconsistent
with that high spirit of delight and triumph with which Kepler surveyed
his discoveries. His was the unpretending ovation of success, not the
ostentatious triumph of ambition; and if a noble pride did occasionally
mingle itself with his feelings, it was the pride of being the chosen
messenger of physical truth, not that of being the favoured possessor of
superior genius. With such a frame of mind, Kepler was necessarily a
Christian. The afflictions with which he was beset confirmed his faith
and brightened his hopes: he bore them in all their variety and severity
with Christian patience; and though he knew that this world was to be
the theatre of his intellectual glory, yet he felt that his rest and his
reward could be found only in another.

It is difficult to form any very intelligible idea of the nature and
extent of Kepler's astrological opinions, and of the degree of credit
which he himself placed in the opinions that he did avow. In his
Principles of Astrology, published in 1602, and in other works, he rails
against the vanity and worthlessness of the ordinary astrology. He
regards those who professed it as knaves and charlatans; and maintains
that the planets and stars exercise no influence whatever over human
affairs. He conceives, however, that certain harmonious configurations
of suitable planets, like the spur to a horse, or a speech to an
audience, have the power of exciting the minds of men to certain general
actions or impulses; so that the only effect of these configurations is
to operate along with the vital soul in producing results which would
not otherwise have taken place. As an example of this, he states that
those who are born when many aspects of the planets occur, _generally_
turn out busy and industrious, whether they be occupied in amassing
wealth, managing public affairs, or prosecuting scientific studies.
Kepler himself was born under a triple configuration, and hence, in his
opinion, his ardour and activity in study; and he informs us that he
knew a lady born under nearly the same configurations, "who not only
makes no progress in literature, but troubles her whole family and
occasions deplorable misery to herself." This excitement of the
faculties of sublunary natures, as he expresses it, by the colours and
aspects and conjunctions of the planets, is regarded by Kepler as a
fact, which he had deduced from observation, and which has "compelled
his unwilling belief." "I have been driven to this," says he, "not by
studying or admiring Plato, but singly and solely by observing seasons,
and noting the aspects by which they are produced. I have seen the state
of the atmosphere almost uniformly disturbed as often as the planets are
in conjunction, or in the other configurations so celebrated among
astrologers. I have noticed its tranquil state either when there are
none or few such aspects, or when they are transitory and of short
duration." Had Kepler been able to examine these hasty and erroneous
deductions by long continued observation, he would soon have found that
the coincidence which he did observe was merely accidental, and he would
have cheerfully acknowledged it. Speculations of this kind, however,
are, from their very nature, less subject to a rigorous scrutiny; and a
long series of observations is necessary either to establish or to
overturn them. The industry of modern observers has now supplied this
defect, and there is no point in science more certain than that the sun,
moon, and planets do not exercise any influence on the general state of
our atmosphere.

The philosophers in Kepler's day, who had studied the phenomena of the
tides, without having any idea of their cause, and who observed that
they were clearly related to the daily motions of the two great
luminaries, may be excused for the extravagance of their belief in
supposing that the planets exercised other influences over "sublunary
nature." Although Kepler, in his Commentaries on Mars, had considered it
probable that the waters of our ocean are attracted by the moon, as iron
is by a loadstone, yet this opinion seems to have been a very transient
one, as he long afterwards, in his System of Harmonies, stated his firm
belief that the earth is an enormous living animal, and enumerates even
the analogies between its habits and those of known animated beings. He
considered the tides as waves produced by the spouting out of water
through its gills, and he explains their relation to the solar and lunar
motions by supposing that the terrene monster has, like other animals,
its daily and nightly alternations of sleeping and waking.

From the consideration of Kepler's astrological opinions, it is an
agreeable transition to proceed to the examination of his high merits as
an astronomer and a philosopher. As an experimental philosopher, or as
an astronomical observer, Kepler does not lay claim to our admiration.
He himself acknowledges, "that for observations his sight was dull, and
for mechanical operations his hand was awkward." He suffered much from
weak eyes, and the delicacy of his constitution did not permit him to
expose himself to the night air. Notwithstanding these hindrances,
however, he added several observations to those of Tycho, which he made
with two instruments that were presented to him by his friend Hoffman,
the President of the States of Styria. These instruments were an iron
sextant, 2½ feet in diameter, and a brass azimuthal quadrant 3½ feet in
diameter, both of which were divided into single minutes of a degree.
They were very seldom used, and we must regard the circumstances which
disqualified Kepler for an observer, as highly favourable to the
developement of those great powers which he directed with undivided
energy to physical astronomy.

Even if Kepler had never turned his attention to the heavens, his
optical labours would have given him a high rank among the original
inquirers of his age; but when we consider him also as the discoverer
of the three great laws which bear his name, we must assign him a rank
next to that of Newton. The history of science does not present us with
any discoveries more truly original, or which required for their
establishment a more powerful and vigorous mind. The speculations of his
predecessors afforded him no assistance. From the cumbrous machinery
adopted by Copernicus, Kepler passed, at one step, to an elliptical
orbit, with the sun in one of its foci, and from that moment astronomy
became a demonstrative science. The splendid discoveries of Newton
sprung immediately from those of Kepler, and completed the great chain
of truths which constitute the laws of the planetary system. The
eccentricity and boldness of Kepler's powers form a striking contrast
with the calm intellect and the enduring patience of Newton. The bright
spark which the genius of the one elicited, was fostered by the sagacity
of the other into a steady and a permanent flame.

Kepler has fortunately left behind him a full account of the methods by
which he arrived at his great discoveries. What other philosophers have
studiously concealed, Kepler has openly avowed, and minutely detailed;
and we have no hesitation in considering these details as the most
valuable present that has ever been given to science, and as deserving
the careful study of all who seek to emulate his immortal achievements.
It has been asserted that Newton made his discoveries by following a
different method; but this is a mere assumption, as Newton has never
favoured the world with any account of the erroneous speculations and
the frequent failures which must have preceded his ultimate success. Had
Kepler done the same, by recording only the final steps of his
inquiries, his method of investigation would have obtained the highest
celebrity, and would have been held up to future ages as a pattern for
their imitation. But such was the candour of his mind, and such his
inordinate love of truth, that he not only recorded his wildest fancies,
but emblazoned even his greatest errors. If Newton had indulged us with
the same insight into his physical inquiries, we should have witnessed
the same processes which were employed by Kepler, modified only by the
different characters and intensities of their imaginative powers.

When Kepler directed his mind to the discovery of a general principle,
he set distinctly before him, and never once lost sight of, the explicit
object of his search. His imagination, now unreined, indulged itself in
the creation and invention of various hypotheses. The most plausible, or
perhaps the most fascinating, of these was then submitted to a rigorous
scrutiny; and the moment it was found to be incompatible with the
results of observation and experiment, it was willingly abandoned, and
another hypothesis submitted to the same severe ordeal. By thus
gradually excluding erroneous views and assumptions, Kepler not only
made a decided approximation to the object of his pursuit, but in the
trials to which his opinions were submitted, and in the observations or
experiments which they called forth, he discovered new facts and arrived
at new views which directed his subsequent inquiries. By pursuing this
method, he succeeded in his most difficult researches, and discovered
those beautiful and profound laws which have been the admiration of
succeeding ages. In tracing the route which he followed, it is easy for
those who live under the light of modern science to say that his
fancies were often wild, and his labour often wasted; but, in judging of
Kepler's methods, we ought to place ourselves in his times, and invest
ourselves with the opinions and the knowledge of his contemporaries.

In the infancy of a science there is no speculation so absurd as not to
merit examination. The most remote and fanciful explanations of facts
have often been found the true ones; and opinions which have in one
century been objects of ridicule, have in the next been admitted among
the elements of our knowledge. The physical world teems with wonders,
and the various forms of matter exhibit to us properties and relations
far more extraordinary than the wildest fancy could have conceived.
Human reason stands appalled before this magnificent display of creative
power, and they who have drunk deepest of its wisdom will be the least
disposed to limit the excursions of physical speculation.

The influence of the imagination as an instrument of research, has, we
think, been much overlooked by those who have ventured to give laws to
philosophy. This faculty is of the greatest value in physical inquiries.
If we use it as a guide, and confide in its indications, it will
infallibly deceive us; but if we employ it as an auxiliary, it will
afford us the most invaluable aid. Its operation is like that of the
light troops which are sent out to ascertain the strength and position
of an enemy. When the struggle commences, their services terminate; and
it is by the solid phalanx of the judgment that the battle must be
fought and won.


G. S. TULLIS, PRINTER, CUPAN.

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  |               Transcriber's Notes and Errata                 |
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  | The following typographical errors have been corrected:      |
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  |               |Error         |Correction    |                |
  |               |              |              |                |
  |               |betwen        |between       |                |
  |               |his his       |his           |                |
  |               |secretry      |secretary     |                |
  |               |there sidence |the residence |                |
  |               |guaging       |gauging       |                |
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