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AN
_INQUIRY_
INTO
THE CAUSES AND EFFECTS
OF
THE VARIOLÆ VACCINÆ.


PRICE 7s. 6d.




AN
_INQUIRY_
INTO
THE CAUSES AND EFFECTS
OF
THE VARIOLÆ VACCINÆ,
A DISEASE
DISCOVERED IN SOME OF THE WESTERN COUNTIES OF ENGLAND,
PARTICULARLY
_GLOUCESTERSHIRE_,
AND KNOWN BY THE NAME OF
THE COW POX.


BY EDWARD JENNER, M.D. F.R.S. &c.

              ----QUID NOBIS CERTIUS IPSIS
  SENSIBUS ESSE POTEST, QUO VERA AC FALSA NOTEMUS.

                                        LUCRETIUS.

London:
PRINTED, FOR THE AUTHOR,
BY SAMPSON LOW, Nº. 7, BERWICK STREET, SOHO:
AND SOLD BY LAW, AVE-MARIA LANE; AND MURRAY AND HIGHLEY, FLEET STREET.

1798.




  TO
  _C. H. PARRY, M.D._
  AT BATH.


  _My dear friend_,

In the present age of scientific investigation, it is remarkable that
a disease of so peculiar a nature as the Cow Pox, which has appeared
in this and some of the neighbouring counties for such a series of
years, should so long have escaped particular attention. Finding the
prevailing notions on the subject, both among men of our profession
and others, extremely vague and indeterminate, and conceiving that
facts might appear at once both curious and useful, I have instituted
as strict an inquiry into the causes and effects of this singular
malady as local circumstances would admit.

The following pages are the result, which, from motives of the most
affectionate regard, are dedicated to you, by

  Your sincere Friend,
  EDWARD JENNER.

  Berkeley, Gloucestershire,
  June 21st, 1798.




AN INQUIRY, _&c. &c._


The deviation of Man from the state in which he was originally placed
by Nature seems to have proved to him a prolific source of Diseases.
From the love of splendour, from the indulgences of luxury, and from
his fondness for amusement, he has familiarised himself with a great
number of animals, which may not originally have been intended for
his associates.

The Wolf, disarmed of ferocity, is now pillowed in the lady's lap[1].
The Cat, the little Tyger of our island, whose natural home is the
forest, is equally domesticated and caressed. The Cow, the Hog, the
Sheep, and the Horse, are all, for a variety of purposes, brought
under his care and dominion.

There is a disease to which the Horse, from his state of
domestication, is frequently subject. The Farriers have termed it
_the Grease_. It is an inflammation and swelling in the heel, from
which issues matter possessing properties of a very peculiar kind,
which seems capable of generating a disease in the Human Body (after
it has undergone the modification which I shall presently speak of),
which bears so strong a resemblance to the Small Pox, that I think it
highly probable it may be the source of that disease.

In this Dairy Country a great number of Cows are kept, and the office
of milking is performed indiscriminately by Men and Maid Servants.
One of the former having been appointed to apply dressings to the
heels of a Horse affected with _the Grease_, and not paying due
attention to cleanliness, incautiously bears his part in milking the
Cows, with some particles of the infectious matter adhering to his
fingers. When this is the case, it commonly happens that a disease is
communicated to the Cows, and from the Cows to the Dairy-maids, which
spreads through the farm until most of the cattle and domestics feel
its unpleasant consequences. This disease has obtained the name of
the Cow Pox. It appears on the nipples of the Cows in the form of
irregular pustules. At their first appearance they are commonly of a
palish blue, or rather of a colour somewhat approaching to livid, and
are surrounded by an erysipelatous inflammation. These pustules,
unless a timely remedy be applied, frequently degenerate into
phagedenic ulcers, which prove extremely troublesome[2]. The animals
become indisposed, and the secretion of milk is much lessened.
Inflamed spots now begin to appear on different parts of the hands of
the domestics employed in milking, and sometimes on the wrists, which
quickly run on to suppuration, first assuming the appearance of the
small vesications produced by a burn. Most commonly they appear about
the joints of the fingers, and at their extremities; but whatever
parts are affected, if the situation will admit, these superficial
suppurations put on a circular form, with their edges more elevated
than their centre, and of a colour distantly approaching to blue.
Absorption takes place, and tumours appear in each axilla. The system
becomes affected--the pulse is quickened; and shiverings succeeded by
heat, with general lassitude and pains about the loins and limbs,
with vomiting, come on. The head is painful, and the patient is now
and then even affected with delirium. These symptoms, varying in
their degrees of violence, generally continue from one day to three
or four, leaving ulcerated sores about the hands, which, from the
sensibility of the parts, are very troublesome, and commonly heal
slowly, frequently becoming phagedenic, like those from whence they
sprung. The lips, nostrils, eyelids, and other parts of the body, are
sometimes affected with sores; but these evidently arise from their
being heedlessly rubbed or scratched with the patient's infected
fingers. No eruptions on the skin have followed the decline of the
feverish symptoms in any instance that has come under my inspection,
one only excepted, and in this case a very few appeared on the arms:
they were very minute, of a vivid red colour, and soon died away
without advancing to maturation; so that I cannot determine whether
they had any connection with the preceding symptoms.

Thus the disease makes its progress from the Horse to the nipple of
the Cow, and from the Cow to the Human Subject.

Morbid matter of various kinds, when absorbed into the system, may
produce effects in some degree similar; but what renders the Cow-pox
virus so extremely singular, is, that the person who has been thus
affected is for ever after secure from the infection of the Small
Pox; neither exposure to the variolous effluvia, nor the insertion of
the matter into the skin, producing this distemper.

In support of so extraordinary a fact, I shall lay before my Reader a
great number of instances[3].

[Footnote 1: The late Mr. John Hunter proved, by experiments, that
the Dog is the Wolf in a degenerated state.]

[Footnote 2: They who attend sick cattle in this country find a
speedy remedy for stopping the progress of this complaint in those
applications which act chemically upon the morbid matter, such as the
solutions of the Vitriolum Zinci, the Vitriolum Cupri, &c.]

[Footnote 3: It is necessary to observe, that pustulous sores
frequently appear spontaneously on the nipples of Cows, and instances
have occurred, though very rarely, of the hands of the servants
employed in milking being affected with sores in consequence, and
even of their feeling an indisposition from absorption. These
pustules are of a much milder nature than those which arise from that
contagion which constitutes the true Cow Pox. They are always free
from the bluish or livid tint so conspicuous in the pustules in that
disease. No erysipelas attends them, nor do they shew any phagedenic
disposition as in the other case, but quickly terminate in a scab
without creating any apparent disorder in the Cow. This complaint
appears at various seasons of the year, but most commonly in the
Spring, when the Cows are first taken from their winter food and fed
with grass. It is very apt to appear also when they are suckling
their young. But this disease is not to be considered as similar in
any respect to that of which I am treating, as it is incapable of
producing any specific effects on the human Constitution. However, it
is of the greatest consequence to point it out here, lest the want of
discrimination should occasion an idea of security from the infection
of the Small Pox, which might prove delusive.]




_CASE I._


JOSEPH MERRET, now an Under Gardener to the Earl of Berkeley, lived
as a Servant with a Farmer near this place in the year 1770, and
occasionally assisted in milking his master's cows. Several horses
belonging to the farm began to have sore heels, which Merret
frequently attended. The cows soon became affected with the Cow Pox,
and soon after several sores appeared on his hands. Swellings and
stiffness in each axilla followed, and he was so much indisposed for
several days as to be incapable of pursuing his ordinary employment.
Previously to the appearance of the distemper among the cows there
was no fresh cow brought into the farm, nor any servant employed who
was affected with the Cow Pox.

In April, 1795, a general inoculation taking place here, Merret was
inoculated with his family; so that a period of twenty-five years had
elapsed from his having the Cow Pox to this time. However, though the
variolous matter was repeatedly inserted into his arm, I found it
impracticable to infect him with it; an efflorescence only, taking on
an erysipelatous look about the centre, appearing on the skin near
the punctured parts. During the whole time that his family had the
Small Pox, one of whom had it very full, he remained in the house
with them, but received no injury from exposure to the contagion.

It is necessary to observe, that the utmost care was taken to
ascertain, with the most scrupulous precision, that no one whose case
is here adduced had gone through the Small Pox previous to these
attempts to produce that disease.

Had these experiments been conducted in a large city, or in a
populous neighbourhood, some doubts might have been entertained; but
here, where population is thin, and where such an event as a person's
having had the Small Pox is always faithfully recorded, no risk of
inaccuracy in this particular can arise.




_CASE II._


SARAH PORTLOCK, of this place, was infected with the Cow Pox, when a
Servant at a Farmer's in the neighbourhood, twenty-seven years
ago[1].

In the year 1792, conceiving herself, from this circumstance, secure
from the infection of the Small Pox, she nursed one of her own
children who had accidentally caught the disease, but no
indisposition ensued.--During the time she remained in the infected
room, variolous matter was inserted into both her arms, but without
any further effect than in the preceding case.

[Footnote 1: I have purposely selected several cases in which the
disease had appeared at a very distant period previous to the
experiments made with variolous matter, to shew that the change
produced in the constitution is not affected by time.]




_CASE III._


JOHN PHILLIPS, a Tradesman of this town, had the Cow Pox at so early
a period as nine years of age. At the age of sixty-two I inoculated
him, and was very careful in selecting matter in its most active
state. It was taken from the arm of a boy just before the
commencement of the eruptive fever, and instantly inserted. It very
speedily produced a sting-like feel in the part. An efflorescence
appeared, which on the fourth day was rather extensive, and some
degree of pain and stiffness were felt about the shoulder; but on the
fifth day these symptoms began to disappear, and in a day or two
after went entirely off, without producing any effect on the system.




_CASE IV._


MARY BARGE, of Woodford, in this parish, was inoculated with
variolous matter in the year 1791. An efflorescence of a palish red
colour soon appeared about the parts where the matter was inserted,
and spread itself rather extensively, but died away in a few days
without producing any variolous symptoms[1]. She has since been
repeatedly employed as a nurse to Small-pox patients, without
experiencing any ill consequences. This woman had the Cow Pox when
she lived in the service of a Farmer in this parish thirty-one years
before.

[Footnote 1: It is remarkable that variolous matter, when the system
is disposed to reject it, should excite inflammation on the part to
which it is applied more speedily than when it produces the Small
Pox. Indeed it becomes almost a criterion by which we can determine
whether the infection will be received or not. It seems as if a
change, which endures through life, had been produced in the action,
or disposition to action, in the vessels of the skin; and it is
remarkable too, that whether this change has been effected by the
Small Pox, or the Cow Pox, that the disposition to sudden cuticular
inflammation is the same on the application of variolous matter.]




_CASE V._


MRS. H----, a respectable Gentlewoman of this town, had the Cow Pox
when very young. She received the infection in rather an uncommon
manner: it was given by means of her handling some of the same
utensils[1] which were in use among the servants of the family, who
had the disease from milking infected cows. Her hands had many of the
Cow-pox sores upon them, and they were communicated to her nose,
which became inflamed and very much swoln. Soon after this event Mrs.
H---- was exposed to the contagion of the Small Pox, where it was
scarcely possible for her to have escaped, had she been susceptible
of it, as she regularly attended a relative who had the disease in so
violent a degree that it proved fatal to him.

In the year 1778 the Small Pox prevailed very much at Berkeley, and
Mrs. H---- not feeling perfectly satisfied respecting her safety (no
indisposition having followed her exposure to the Small Pox) I
inoculated her with active variolous matter. The same appearance
followed as in the preceding cases--an efflorescence on the arm
without any effect on the constitution.

[Footnote 1: When the Cow Pox has prevailed in the dairy, it has
often been communicated to those who have not milked the cows, by the
handle of the milk pail.]




_CASE VI._


It is a fact so well known among our Dairy Farmers, that those who
have had the Small Pox either escape the Cow Pox or are disposed to
have it slightly; that as soon as the complaint shews itself among
the cattle, assistants are procured, if possible, who are thus
rendered less susceptible of it, otherwise the business of the farm
could scarcely go forward.

In the month of May, 1796, the Cow Pox broke out at Mr. Baker's, a
Farmer who lives near this place. The disease was communicated by
means of a cow which was purchased in an infected state at a
neighbouring fair, and not one of the Farmer's cows (consisting of
thirty) which were at that time milked escaped the contagion. The
family consisted of a man servant, two dairymaids, and a servant boy,
who, with the Farmer himself, were twice a day employed in milking
the cattle. The whole of this family, except Sarah Wynne, one of the
dairymaids, had gone through the Small Pox. The consequence was, that
the Farmer and the servant boy escaped the infection of the Cow Pox
entirely, and the servant man and one of the maid servants had each
of them nothing more than a sore on one of their fingers, which
produced no disorder in the system. But the other dairymaid, Sarah
Wynne, who never had the Small Pox, did not escape in so easy a
manner. She caught the complaint from the cows, and was affected with
the symptoms described in the 5th page in so violent a degree, that
she was confined to her bed, and rendered incapable for several days
of pursuing her ordinary vocations in the farm.

March 28th, 1797, I inoculated this girl, and carefully rubbed the
variolous matter into two slight incisions made upon the left arm. A
little inflammation appeared in the usual manner around the parts
where the matter was inserted, but so early as the fifth day it
vanished entirely without producing any effect on the system.




_CASE VII._


Although the preceding history pretty clearly evinces that the
constitution is far less susceptible of the contagion of the Cow Pox
after it has felt that of the Small Pox, and although in general, as
I have observed, they who have had the Small Pox, and are employed in
milking cows which are infected with the Cow Pox, either escape the
disorder, or have sores on the hands without feeling any general
indisposition, yet the animal economy is subject to some variation in
this respect, which the following relation will point out:

In the summer of the year 1796 the Cow Pox appeared at the Farm of
Mr. Andrews, a considerable dairy adjoining to the town of Berkeley.
It was communicated, as in the preceding instance, by an infected cow
purchased at a fair in the neighbourhood. The family consisted of the
Farmer, his wife, two sons, a man and a maid servant; all of whom,
except the Farmer (who was fearful of the consequences), bore a part
in milking the cows. The whole of them, exclusive of the man servant,
had regularly gone through the Small Pox; but in this case no one who
milked the cows escaped the contagion. All of them had sores upon
their hands, and some degree of general indisposition, preceded by
pains and tumours in the axillæ: but there was no comparison in the
severity of the disease as it was felt by the servant man, who had
escaped the Small Pox, and by those of the family who had not, for,
while he was confined to his bed, they were able, without much
inconvenience, to follow their ordinary business.

February the 13th, 1797, I availed myself of an opportunity of
inoculating William Rodway, the servant man above alluded to.
Variolous matter was inserted into both his arms; in the right by
means of superficial incisions, and into the left by slight punctures
into the cutis. Both were perceptibly inflamed on the third day.
After this the inflammation about the punctures soon died away, but a
small appearance of erysipelas was manifest about the edges of the
incisions till the eighth day, when a little uneasiness was felt for
the space of half an hour in the right axilla. The inflammation then
hastily disappeared without producing the most distant mark of
affection of the system.




_CASE VIII._


ELIZABETH WYNNE, aged fifty-seven, lived as a servant with a
neighbouring Farmer thirty-eight years ago. She was then a dairymaid,
and the Cow Pox broke out among the cows. She caught the disease with
the rest of the family, but, compared with them, had it in a very
slight degree, one very small sore only breaking out on the little
finger of her left hand, and scarcely any perceptible indisposition
following it.

As the malady had shewn itself in so slight a manner, and as it had
taken place at so distant a period of her life, I was happy with the
opportunity of trying the effects of variolous matter upon her
constitution, and on the 28th of March, 1797, I inoculated her by
making two superficial incisions on the left arm, on which the matter
was cautiously rubbed. A little efflorescence soon appeared, and a
tingling sensation was felt about the parts where the matter was
inserted until the third day, when both began to subside, and so
early as the fifth day it was evident that no indisposition would
follow.




_CASE IX._


Although the Cow Pox shields the constitution from the Small Pox, and
the Small Pox proves a protection against its own future poison, yet
it appears that the human body is again and again susceptible of the
infectious matter of the Cow Pox, as the following history will
demonstrate:

William Smith, of Pyrton in this parish, contracted this disease when
he lived with a neighbouring Farmer in the year 1780. One of the
horses belonging to the farm had sore heels, and it fell to his lot
to attend him. By these means the infection was carried to the cows,
and from the cows it was communicated to Smith. On one of his hands
were several ulcerated sores, and he was affected with such symptoms
as have been before described.

In the year 1791 the Cow Pox broke out at another farm where he then
lived as a servant, and he became affected with it a second time; and
in the year 1794 he was so unfortunate as to catch it again. The
disease was equally as severe the second and third time as it was on
the first[1].

In the spring of the year 1795 he was twice inoculated, but no
affection of the system could be produced from the variolous matter;
and he has since associated with those who had the Small Pox in its
most contagious state without feeling any effect from it.

[Footnote 1: This is not the case in general--a second attack is
commonly very slight, and so, I am informed, it is among the cows.]




_CASE X._


SIMON NICHOLS lived as a servant with Mr. Bromedge, a gentleman who
resides on his own farm in this parish, in the year 1782. He was
employed in applying dressings to the sore heels of one of his
master's horses, and at the same time assisted in milking the cows.
The cows became affected in consequence, but the disease did not shew
itself on their nipples till several weeks after he had begun to
dress the horse. He quitted Mr. Bromedge's service, and went to
another farm without any sores upon him; but here his hands soon
began to be affected in the common way, and he was much indisposed
with the usual symptoms. Concealing the nature of the malady from Mr.
Cole, his new master, and being there also employed in milking, the
Cow Pox was communicated to the cows.

Some years afterwards Nichols was employed in a farm where the Small
Pox broke out, when I inoculated him with several other patients,
with whom he continued during the whole time of their confinement.
His arm inflamed, but neither the inflammation nor his associating
with the inoculated family produced the least effect upon his
constitution.




_CASE XI._


WILLIAM STINCHCOMB was a fellow servant with Nichols at Mr.
Bromedge's Farm at the time the cattle had the Cow Pox, and he was
unfortunately infected by them. His left hand was very severely
affected with several corroding ulcers, and a tumour of considerable
size appeared in the axilla of that side. His right hand had only one
small sore upon it, and no tumour discovered itself in the
corresponding axilla.

In the year 1792 Stinchcomb was inoculated with variolous matter, but
no consequences ensued beyond a little inflammation in the arm for a
few days. A large party were inoculated at the same time, some of
whom had the disease in a more violent degree than is commonly seen
from inoculation. He purposely associated with them, but could not
receive the Small Pox.

During the sickening of some of his companions, their symptoms so
strongly recalled to his mind his own state when sickening with the
Cow Pox, that he very pertinently remarked their striking similarity.




_CASE XII._


The Paupers of the village of Tortworth, in this county, were
inoculated by Mr. Henry Jenner, Surgeon, of Berkeley, in the year
1795. Among them, eight patients presented themselves who had at
different periods of their lives had the Cow Pox. One of them, Hester
Walkley, I attended with that disease when she lived in the service
of a Farmer in the same village in the year 1782; but neither this
woman, nor any other of the patients who had gone through the Cow
Pox, received the variolous infection either from the arm or from
mixing in the society of the other patients who were inoculated at
the same time. This state of security proved a fortunate
circumstance, as many of the poor women were at the same time in a
state of pregnancy.




_CASE XIII._


One instance has occurred to me of the system being affected from the
matter issuing from the heels of horses, and of its remaining
afterwards unsusceptible of the variolous contagion; another, where
the Small Pox appeared obscurely; and a third, in which its complete
existence was positively ascertained.

First, THOMAS PEARCE, is the son of a Smith and Farrier near to this
place. He never had the Cow Pox; but, in consequence of dressing
horses with sore heels at his father's, when a lad, he had sores on
his fingers which suppurated, and which occasioned a pretty severe
indisposition. Six years afterwards I inserted variolous matter into
his arm repeatedly, without being able to produce any thing more than
slight inflammation, which appeared very soon after the matter was
applied, and afterwards I exposed him to the contagion of the Small
Pox with as little effect[1].

[Footnote 1: It is a remarkable fact, and well known to many, that we
are frequently foiled in our endeavours to communicate the Small Pox
by inoculation to blacksmiths, who in the country are farriers. They
often, as in the above instance, either resist the contagion
entirely, or have the disease anomalously. Shall we not be able now
to account for this on a rational principle?]




_CASE XIV._


Secondly, Mr. JAMES COLE, a Farmer in this parish, had a disease from
the same source as related in the preceding case, and some years
after was inoculated with variolous matter. He had a little pain in
the axilla, and felt a slight indisposition for three or four hours.
A few eruptions shewed themselves on the forehead, but they very soon
disappeared without advancing to maturation.




_CASE XV._


Although in the two former instances the system seemed to be secured,
or nearly so, from variolous infection, by the absorption of matter
from sores produced by the diseased heels of horses, yet the
following case decisively proves that this cannot be entirely relied
upon, until a disease has been generated by the morbid matter from
the horse on the nipple of the cow, and passed through that medium to
the human subject.

Mr. ABRAHAM RIDDIFORD, a Farmer at Stone in this parish, in
consequence of dressing a mare that had sore heels, was affected with
very painful sores in both his hands, tumours in each axilla, and
severe and general indisposition. A Surgeon in the neighbourhood
attended him, who, knowing the similarity between the appearance of
the sores upon his hands and those produced by the Cow Pox, and being
acquainted also with the effects of that disease on the human
constitution, assured him that he never need to fear the infection of
the Small Pox; but this assertion proved fallacious, for, on being
exposed to the infection upwards of twenty years afterwards, he
caught the disease, which took its regular course in a very mild way.
There certainly was a difference perceptible, although it is not easy
to describe it, in the general appearance of the pustules from that
which we commonly see. Other practitioners, who visited the patient
at my request, agreed with me in this point, though there was no room
left for suspicion as to the reality of the disease, as I inoculated
some of his family from the pustules, who had the Small Pox, with its
usual appearances, in consequence.




_CASE XVI._


SARAH NELMES, a dairymaid at a Farmer's near this place, was infected
with the Cow Pox from her master's cows in May, 1796. She received
the infection on a part of the hand which had been previously in a
slight degree injured by a scratch from a thorn. A large pustulous
sore and the usual symptoms accompanying the disease were produced in
consequence. The pustule was so expressive of the true character of
the Cow Pox, as it commonly appears upon the hand, that I have given
a representation of it in the annexed plate. The two small pustules
on the wrists arose also from the application of the virus to some
minute abrasions of the cuticle, but the livid tint, if they ever had
any, was not conspicuous at the time I saw the patient. The pustule
on the fore finger shews the disease in an earlier stage. It did not
actually appear on the hand of this young woman, but was taken from
that of another, and is annexed for the purpose of representing the
malady after it has newly appeared.




_CASE XVII._


The more accurately to observe the progress of the infection, I
selected a healthy boy, about eight years old, for the purpose of
inoculation for the Cow Pox. The matter was taken from a sore on the
hand of a dairymaid[1], who was infected by her master's cows, and it
was inserted, on the 14th of May, 1796, into the arm of the boy by
means of two superficial incisions, barely penetrating the cutis,
each about half an inch long.

[Illustration]

On the seventh day he complained of uneasiness in the axilla, and on
the ninth he became a little chilly, lost his appetite, and had a
slight head-ach. During the whole of this day he was perceptibly
indisposed, and spent the night with some degree of restlessness, but
on the day following he was perfectly well.

The appearance of the incisions in their progress to a state of
maturation were much the same as when produced in a similar manner by
variolous matter. The only difference which I perceived was, in the
state of the limpid fluid arising from the action of the virus, which
assumed rather a darker hue, and in that of the efflorescence
spreading round the incisions, which had more of an erysipelatous
look than we commonly perceive when variolous matter has been made
use of in the same manner; but the whole died away (leaving on the
inoculated parts scabs and subsequent eschars) without giving me or
my patient the least trouble.

In order to ascertain whether the boy, after feeling so slight an
affection of the system from the Cow-pox virus, was secure from the
contagion of the Small-pox, he was inoculated the 1st of July
following with variolous matter, immediately taken from a pustule.
Several slight punctures and incisions were made on both his arms,
and the matter was carefully inserted, but no disease followed. The
same appearances were observable on the arms as we commonly see when
a patient has had variolous matter applied, after having either the
Cow-pox or the Small-pox. Several months afterwards, he was again
inoculated with variolous matter, but no sensible effect was produced
on the constitution.

Here my researches were interrupted till the spring of the year 1798,
when from the wetness of the early part of the season, many of the
farmers' horses in this neighbourhood were affected with sore heels,
in consequence of which the Cow-pox broke out among several of our
dairies, which afforded me an opportunity of making further
observations upon this curious disease.

A mare, the property of a person who keeps a dairy in a neighbouring
parish, began to have sore heels the latter end of the month of
February 1798, which were occasionally washed by the servant men of
the farm, Thomas Virgoe, William Wherret, and William Haynes, who in
consequence became affected with sores in their hands, followed by
inflamed lymphatic glands in the arms and axillæ, shiverings
succeeded by heat, lassitude and general pains in the limbs. A single
paroxysm terminated the disease; for within twenty-four hours they
were free from general indisposition, nothing remaining but the sores
on their hands. Haynes and Virgoe, who had gone through the Small-pox
from inoculation, described their feelings as very similar to those
which affected them on sickening with that malady. Wherret never had
had the Small-pox. Haynes was daily employed as one of the milkers at
the farm, and the disease began to shew itself among the cows about
ten days after he first assisted in washing the mare's heels. Their
nipples became sore in the usual way, with blueish pustules; but as
remedies were early applied they did not ulcerate to any extent.

[Footnote 1: From the sore on the hand of Sarah Nelmes.--See the
preceding case and the plate.]




_CASE XVIII._


JOHN BAKER, a child of five years old, was inoculated March 16, 1798,
with matter taken from a pustule on the hand of Thomas Virgoe, one of
the servants who had been infected from the mare's heels. He became
ill on the 6th day with symptoms similar to those excited by Cow-pox
matter. On the 8th day he was free from indisposition.

There was some variation in the appearance of the pustule on the arm.
Although it somewhat resembled a Small-pox pustule, yet its
similitude was not so conspicuous as when excited by matter from the
nipple of the cow, or when the matter has passed from thence through
the medium of the human subject.--(See Plate, No. 2.)

[Illustration]

This experiment was made to ascertain the progress and subsequent
effects of the disease when thus propagated. We have seen that the
virus from the horse, when it proves infectious to the human subject
is not to be relied upon as rendering the system secure from
variolous infection, but that the matter produced by it upon the
nipple of the cow is perfectly so. Whether its passing from the horse
through the human constitution, as in the present instance, will
produce a similar effect, remains to be decided. This would now have
been effected, but the boy was rendered unfit for inoculation from
having felt the effects of a contagious fever in a work-house, soon
after this experiment was made.




_CASE XIX._


WILLIAM SUMMERS, a child of five years and a half old was inoculated
the same day with Baker, with matter taken from the nipples of one of
the infected cows, at the farm alluded to in page 35. He became
indisposed on the 6th day, vomited once, and felt the usual slight
symptoms till the 8th day, when he appeared perfectly well. The
progress of the pustule, formed by the infection of the virus was
similar to that noticed in Case XVII., with this exception, its being
free from the livid tint observed in that instance.




_CASE XX._


From William Summers the disease was transfered to William Pead a boy
of eight years old, who was inoculated March 28th. On the 6th day he
complained of pain in the axilla, and on the 7th was affected with
the common symptoms of a patient sickening with the Small-pox from
inoculation, which did not terminate 'till the 3d day after the
seizure. So perfect was the similarity to the variolous fever that I
was induced to examine the skin, conceiving there might have been
some eruptions, but none appeared. The efflorescent blush around the
part punctured in the boy's arm was so truly characteristic of that
which appears on variolous inoculation, that I have given a
representation of it. The drawing was made when the pustule was
beginning to die away, and the areola retiring from the centre. (See
Plate, No. 3.)

[Illustration]




_CASE XXI._


April 5th. Several children and adults were inoculated from the arm
of William Pead. The greater part of them sickened on the 6th day,
and were well on the 7th, but in three of the number a secondary
indisposition arose in consequence of an extensive erysipelatous
inflammation which appeared on the inoculated arms. It seemed to
arise from the state of the pustule, which spread out, accompanied
with some degree of pain, to about half the diameter of a six-pence.
One of these patients was an infant of half a year old. By the
application of mercurial ointment to the inflamed parts (a treatment
recommended under similar circumstances in the inoculated Small-pox)
the complaint subsided without giving much trouble.

HANNAH EXCELL an healthy girl of seven years old, and one of the
patients above mentioned, received the infection from the insertion
of the virus under the cuticle of the arm in three distinct points.
The pustules which arose in consequence, so much resembled, on the
12th day, those appearing from the insertion of variolous matter,
that an experienced Inoculator would scarcely have discovered a shade
of difference at that period. Experience now tells me that almost the
only variation which follows consists in the pustulous fluids
remaining limpid nearly to the time of its total disappearance; and
not, as in the direct Small-pox, becoming purulent.--(See Plate, No.
4.)




_CASE XXII._


From the arm of this girl matter was taken and inserted April 12th
into the arms of John Marklove one year and a half old,

  Robert F. Jenner, eleven months old,
  Mary Pead, 5 years old, and
  Mary James, 6 years old.

[Illustration]

Among these Robert F. Jenner did not receive the infection. The arms
of the other three inflamed properly and began to affect the system
in the usual manner; but being under some apprehensions from the
preceding Cases that a troublesome erysipelas might arise, I
determined on making an experiment with the view of cutting off its
source. Accordingly after the patients had felt an indisposition of
about twelve hours, I applied in two of these Cases out of the three,
on the vesicle formed by the virus, a little mild caustic, composed
of equal parts of quick-lime and soap, and suffered it to remain on
the part six hours[1]. It seemed to give the children but little
uneasiness, and effectually answered my intention in preventing the
appearance of erysipelas. Indeed it seemed to do more, for in half an
hour after its application, the indisposition of the children
ceased[2]. These precautions were perhaps unnecessary as the arm of
the third child, Mary Pead, which was suffered to take its common
course, scabbed quickly, without any erysipelas.

[Footnote 1: Perhaps a few touches with the lapis septicus would have
proved equally efficacious.]

[Footnote 2: What effect would a similar treatment produce in
inoculation for the Small-pox?]




_CASE XXIII._


From this child's arm matter was taken and transferred to that of J.
Barge, a boy of seven years old. He sickened on the 8th day, went
through the disease with the usual slight symptoms, and without any
inflammation on the arm beyond the common efflorescence surrounding
the pustule, an appearance so often seen in inoculated Small-pox.

After the many fruitless attempts to give the Small-pox to those who
had had the Cow-pox, it did not appear necessary, nor was it
convenient to me, to inoculate the whole of those who had been the
subjects of these late trials; yet I thought it right to see the
effects of variolous matter on some of them, particularly William
Summers, the first of these patients who had been infected with
matter taken from the cow. He was therefore inoculated with variolous
matter from a fresh pustule; but, as in the preceding Cases, the
system did not feel the effects of it in the smallest degree. I had
an opportunity also of having this boy and William Pead inoculated by
my Nephew, Mr. Henry Jenner, whose report to me is as follows: "I
have inoculated Pead and Barge, two of the boys whom you lately
infected with the Cow-pox. On the 2d day the incisions were inflamed
and there was a pale inflammatory stain around them. On the 3d day
these appearances were still increasing and their arms itched
considerably. On the 4th day, the inflammation was evidently
subsiding, and on the 6th it was scarcely perceptible. No symptom of
indisposition followed.

To convince myself that the variolous matter made use of was in a
perfect state, I at the same time inoculated a patient with some of
it who never had gone through the Cow-pox, and it produced the
Small-pox in the usual regular manner."

These experiments afforded me much satisfaction, they proved that the
matter in passing from one human subject to another, through five
gradations, lost none of its original properties, J. Barge being the
fifth who received the infection successively from William Summers,
the boy to whom it was communicated from the cow.

     *     *     *     *     *

I shall now conclude this Inquiry with some general observations on
the subject and on some others which are interwoven with it.

Although I presume it may be unnecessary to produce further testimony
in support of my assertion "that the Cow-pox protects the human
constitution from the infection of the Small-pox," yet it affords me
considerable satisfaction to say, that Lord Somerville, the President
of the Board of Agriculture, to whom this paper was shewn by Sir
Joseph Banks, has found upon inquiry that the statements were
confirmed by the concuring testimony of Mr. Dolland, a surgeon, who
resides in a dairy country remote from this, in which these
observations were made. With respect to the opinion adduced "that the
source of the infection is a peculiar morbid matter arising in the
horse," although I have not been able to prove it from actual
experiments conducted immediately under my own eye, yet the evidence
I have adduced appears sufficient to establish it.

They who are not in the habit of conducting experiments may not be
aware of the coincidence of circumstances necessary for their being
managed so as to prove perfectly decisive; nor how often men engaged
in professional pursuits are liable to interruptions which disappoint
them almost at the instant of their being accomplished: however, I
feel no room for hesitation respecting the common origin of the
disease, being well convinced that it never appears among the cows
(except it can be traced to a cow introduced among the general herd
which has been previously infected, or to an infected servant),
unless they have been milked by some one who, at the same time, has
the care of a horse affected with diseased heels.

The spring of the year 1797, which I intended particularly to have
devoted to the completion of this investigation, proved, from its
dryness, remarkably adverse to my wishes; for it frequently happens,
while the farmers' horses are exposed to the cold rains which fall at
that season that their heels become diseased, and no Cow-pox then
appeared in the neighbourhood.

The active quality of the virus from the horses' heels is greatly
increased after it has acted on the nipples of the cow, as it rarely
happens that the horse affects his dresser with sores, and as rarely
that a milk-maid escapes the infection when she milks infected cows.
It is most active at the commencement of the disease, even before it
has acquired a pus-like appearance; indeed I am not confident whether
this property in the matter does not entirely cease as soon as it is
secreted in the form of pus. I am induced to think it does cease[1],
and that it is the thin darkish-looking fluid only, oozing from the
newly-formed cracks in the heels, similar to what sometimes appears
from erysipelatous blisters, which gives the disease. Nor am I
certain that the nipples of the cows are at all times in a state to
receive the infection. The appearance of the disease in the spring
and the early part of the summer, when they are disposed to be
affected with spontaneous eruptions so much more frequently than at
other seasons, induces me to think, that the virus from the horse
must be received upon them when they are in this state, in order to
produce effects: experiments, however, must determine these points.
But it is clear that when the Cow-pox virus is once generated, that
the cows cannot resist the contagion, in whatever state their nipples
may chance to be, if they are milked with an infected hand.

Whether the matter, either from the cow or the horse will affect the
sound skin of the human body, I cannot positively determine; probably
it will not, unless on those parts where the cuticle is extremely
thin, as on the lips for example. I have known an instance of a poor
girl who produced an ulceration on her lip by frequently holding her
finger to her mouth to cool the raging of a Cow-pox sore by blowing
upon it. The hands of the farmers' servants here, from the nature of
their employments, are constantly exposed to those injuries which
occasion abrasions of the cuticle, to punctures from thorns and such
like accidents; so that they are always in a state to feel the
consequences of exposure to infectious matter.

It is singular to observe that the Cow-pox virus, although it renders
the constitution unsusceptible of the variolous, should,
nevertheless, leave it unchanged with respect to its own action. I
have already produced an instance[2] to point out this, and shall now
corroborate it with another.

Elizabeth Wynne, who had the Cow-pox in the year 1759, was inoculated
with variolous matter, without effect, in the year 1797, and again
caught the Cow-pox in the year 1798. When I saw her, which was on the
8th day after she received the infection, I found her affected with
general lassitude, shiverings, alternating with heat, coldness of the
extremities, and a quick and irregular pulse. These symptoms were
preceded by a pain in the axilla. On her hand was one large pustulous
sore, which resembled that delinated in Plate No. 1.

It is curious also to observe, that the virus, which with respect to
its effects is undetermined and uncertain previously to its passing
from the horse through the medium of the cow, should then not only
become more active, but should invariably and completely possess
those specific properties which induce in the human constitution
symptoms similar to those of the variolous fever, and effect in it
that peculiar change which for ever renders it unsusceptible of the
variolous contagion.

May it not, then, be reasonably conjectured, that the source of the
Small-pox is morbid matter of a peculiar kind, generated by a disease
in the horse, and that accidental circumstances may have again and
again arisen, still working new changes upon it, until it has
acquired the contagious and malignant form under which we now
commonly see it making its devastations amongst us? And, from a
consideration of the change which the infectious matter undergoes
from producing a disease on the cow, may we not conceive that many
contagious diseases, now prevalent among us, may owe their present
appearance not to a simple, but to a compound origin? For example, is
it difficult to imagine that the measles, the scarlet fever, and the
ulcerous sore throat with a spotted skin, have all sprung from the
same source, assuming some variety in their forms according to the
nature of their new combinations? The same question will apply
respecting the origin of many other contagious diseases, which bear a
strong analogy to each other.

There are certainly more forms than one, without considering the
common variation between the confluent and distinct, in which the
Small-pox appears in what is called the natural way.--About seven
years ago a species of Small-pox spread through many of the towns and
villages of this part of Gloucestershire: it was of so mild a nature,
that a fatal instance was scarcely ever heard of, and consequently so
little dreaded by the lower orders of the community, that they
scrupled not to hold the same intercourse with each other as if no
infectious disease had been present among them. I never saw nor heard
of an instance of its being confluent. The most accurate manner,
perhaps, in which I can convey an idea of it is, by saying, that had
fifty individuals been taken promiscuously and infected by exposure
to this contagion, they would have had as mild and light a disease as
if they had been inoculated with variolous matter in the usual way.
The harmless manner in which it shewed itself could not arise from
any peculiarity either in the season or the weather, for I watched
its progress upwards of a year without perceiving any variation in
its general appearance. I consider it then as a _variety_ of the
Small-pox[3].

In some of the preceding cases I have noticed the attention that was
paid to the state of the variolous matter previous to the experiment
of inserting it into the arms of those who had gone through the
Cow-pox. This I conceived to be of great importance in conducting
these experiments, and were it always properly attended to by those
who inoculate for the Small-pox, it might prevent much subsequent
mischief and confusion. With the view of enforcing so necessary a
precaution, I shall take the liberty of digressing so far as to point
out some unpleasant facts, relative to mismanagement in this
particular, which have fallen under my own observation.

A Medical Gentleman (now no more), who for many years inoculated in
this neighbourhood, frequently preserved the variolous matter
intended for his use, on a piece of lint or cotton, which, in its
fluid state was put into a vial, corked, and conveyed into a warm
pocket; a situation certainly favourable for speedily producing
putrefaction in it. In this state (not unfrequently after it had been
taken several days from the pustules) it was inserted into the arms
of his patients, and brought on inflammation of the incised parts,
swellings of the axillary glands, fever, and sometimes eruptions. But
what was this disease? Certainly not the Small-pox; for the matter
having from putrefaction lost, or suffered a derangement in its
specific properties, was no longer capable of producing that malady,
those who had been inoculated in this manner being as much subject to
the contagion of the Small-pox, as if they had never been under the
influence of this artificial disease; and many, unfortunately, fell
victims to it, who thought themselves in perfect security. The same
unfortunate circumstance of giving a disease, supposed to be the
Small-pox, with inefficaceous variolous matter, having occurred under
the direction of some other practitioners within my knowledge, and
probably from the same incautious method of securing the variolous
matter, I avail myself of this opportunity of mentioning what I
conceive to be of great importance; and, as a further cautionary
hint, I shall again digress so far as to add another observation on
the subject of Inoculation.

Whether it be yet ascertained by experiment, that the quantity of
variolous matter inserted into the skin makes any difference with
respect to the subsequent mildness or violence of the disease, I know
not; but I have the strongest reason for supposing that is either the
punctures or incisions be made so deep as to go _through_ it, and
wound the adipose membrane, that the risk of bringing on a violent
disease is greatly increased. I have known an inoculator, whose
practice was "to cut deep enough (to use his own expression) to see a
bit of fat," and there to lodge the matter. The great number of bad
Cases, independent of inflammations and abscesses on the arms, and
the fatality which attended this practice was almost inconceivable;
and I cannot account for it on any other principle than that of the
matter being placed in this situation instead of the skin.

It was the practice of another, whom I well remember, to pinch up a
small portion of the skin on the arms of his patients and to pass
through it a needle, with a thread attached to it previously dipped
in variolous matter. The thread was lodged in the perforated part,
and consequently left in contact with the cellular membrane. This
practice was attended with the same ill success as the former.
Although it is very improbable that any one would now inoculate in
this rude way by design, yet these observations may tend to place a
double guard over the lancet, when infants, whose skins are
comparatively so very thin, fall under the care of the inoculator.

A very respectable friend of mine, Dr. Hardwicke, of Sodbury in this
county, inoculated great numbers of patients previous to the
introduction of the more modern method by Sutton, and with such
success, that a fatal instance occurred as rarely as since that
method has been adopted. It was the doctor's practice to make as
slight an incision as possible _upon_ the skin, and there to lodge a
thread saturated with the variolous matter. When his patients became
indisposed, agreeably to the custom then prevailing, they were
directed to go to bed and were kept moderately warm. Is it not
probable then, that the success of the modern practice may depend
more upon the method of invariably depositing the virus in or upon
the skin, than on the subsequent treatment of the disease?

I do not mean to insinuate that exposure to cool air, and suffering
the patient to drink cold water when hot and thirsty, may not
moderate the eruptive symptoms and lessen the number of pustules;
yet, to repeat my former observation, I cannot account for the
uninterrupted success, or nearly so, of one practitioner, and the
wretched state of the patients under the care of another, where, in
both instances, the general treatment did not differ essentially,
without conceiving it to arise from the different modes of inserting
the matter for the purpose of producing the disease. As it is not the
identical matter inserted which is absorbed into the constitution,
but that which is, by some peculiar process in the animal economy,
generated by it, is it not probable that different parts of the human
body may prepare or modify the virus differently? Although the skin,
for example, adipose membrane, or mucous membranes are all capable of
producing the variolous virus by the stimulus given by the particles
originally deposited upon them, yet I am induced to conceive that
each of these parts is capable of producing some variation in the
qualities of the matter previous to its affecting the constitution.
What else can constitute the difference between the Small-pox when
communicated casually or in what has been termed the natural way, or
when brought on artificially through the medium of the skin? After
all, are the variolous particles, possessing their true specific and
contagious principles, ever taken up and conveyed by the lymphatics
unchanged into the blood vessels? I imagine not. Were this the case,
should we not find the blood sufficiently loaded with them in some
stages of the Small-pox to communicate the disease by inserting it
under the cuticle, or by spreading it on the surface of an ulcer? Yet
experiments have determined the impracticability of its being given
in this way; although it has been proved that variolous matter when
much diluted with water, and applied to the skin in the usual manner,
will produce the disease. But it would be digressing beyond a proper
boundary, to go minutely into this subject here.

At what period the Cow-pox was first noticed here is not upon record.
Our oldest farmers were not unacquainted with it in their earliest
days, when it appeared among their farms without any deviation from
the phænomena which it now exhibits. Its connection with the
Small-pox seems to have been unknown to them. Probably the general
introduction of inoculation first occasioned the discovery.

Its rise in this country may not have been of very remote date, as
the practice of milking cows might formerly have been in the hands of
women only; which I believe is the case now in some other dairy
countries, and, consequently that the cows might not in former times
have been exposed to the contagious matter brought by the men
servants from the heels of horses[4]. Indeed a knowledge of the
source of the infection is new in the minds of most of the farmers in
this neighbourhood, but it has at length produced good consequences;
and it seems probable from the precautions they are now disposed to
adopt, that the appearance of the Cow-pox here may either be entirely
extinguished or become extremely rare.

Should it be asked whether this investigation is a matter of mere
curiosity, or whether it tends to any beneficial purpose? I should
answer, that notwithstanding the happy effects of Inoculation, with
all the improvements which the practice has received since its first
introduction into this country, it not very unfrequently produces
deformity of the skin, and sometimes, under the best management,
proves fatal.

These circumstances must naturally create in every instance some
degree of painful solicitude for its consequences. But as I have
never known fatal effects arise from the Cow-pox, even when impressed
in the most unfavourable manner, producing extensive inflammations
and suppurations on the hands; and as it clearly appears that this
disease leaves the constitution in a state of perfect security from
the infection of the Small-pox, may we not infer that a mode of
Inoculation may be introduced preferable to that at present adopted,
especially among those families, which, from previous circumstances
we may judge to be predisposed to have the disease unfavourably? It
is an excess in the number of pustules which we chiefly dread in the
Small-pox; but, in the Cow-pox, no pustules appear, nor does it seem
possible for the contagious matter to produce the disease from
effluvia, or by any other means than contact, and that probably not
simply between the virus and the cuticle; so that a single individual
in a family might at any time receive it without the risk of
infecting the rest, or of spreading a distemper that fills a country
with terror. Several instances have come under my observation which
justify the assertion that the disease cannot be propagated by
effluvia. The first boy whom I inoculated with the matter of Cow-pox,
slept in a bed, while the experiment was going forward, with two
children who never had gone through either that disease or the
Small-pox, without infecting either of them.

A young woman who had the Cow-pox to a great extent, several sores
which maturated having appeared on the hands and wrists, slept in the
same bed with a fellow-dairy maid who never had been infected with
either the Cow-pox or the Small-pox, but no indisposition followed.

Another instance has occurred of a young woman on whose hands were
several large suppurations from the Cow-pox, who was at the same time
a daily nurse to an infant, but the complaint was not communicated to
the child.

In some other points of view, the inoculation of this disease appears
preferable to the variolous inoculation.

In constitutions predisposed to scrophula, how frequently we see the
inoculated Small-pox, rouse into activity that distressful malady.
This circumstance does not seem to depend on the manner in which the
distemper has shewn itself, for it has as frequently happened among
those who have had it mildly, as when it has appeared in the contrary
way.

There are many, who from some peculiarity in the habit resist the
common effects of variolous matter inserted into the skin, and who
are in consequence haunted through life with the distressing idea of
being insecure from subsequent infection. A ready mode of dissipating
anxiety originating from such a cause must now appear obvious. And,
as we have seen that the constitution may at any time be made to feel
the febrile attack of Cow-pox, might it not, in many chronic diseases
be introduced into the system, with the probability of affording
relief, upon well-known physiological principles?

Although I say the system may at any time be made to feel the febrile
attack of Cow-pox, yet I have a single instance before me where the
virus acted locally only, but it is not in the least probable that
the same person would resist the action both of the Cow-pox virus and
the variolous.

Elizabeth Sarsenet lived as a dairy maid at Newpark farm, in this
parish. All the cows and the servants employed in milking had the
Cow-pox; but this woman, though she had several sores upon her
fingers, felt no tumors in the axillæ, nor any general indisposition.
 On being afterwards casually exposed to variolous infection, she had
the Small-pox in a mild way.--Hannah Pick, another of the dairy maids
who was a fellow-servant with Elizabeth Sarsenet when the distemper
broke out at the farm was, at the same time infected; but this young
woman had not only sores upon her hands, but felt herself also much
indisposed for a day or two. After this, I made several attempts to
give her the Small-pox by inoculation, but they all proved fruitless.
From the former Case then we see that the animal economy is subject
to the same laws in one disease as the other.

The following Case which has very lately occurred renders it highly
probable that not only the heels of the horse, but other parts of the
body of that animal, are capable of generating the virus which
produces the Cow-pox.

An extensive inflammation of the erysipelatous kind, appeared without
any apparent cause upon the upper part of the thigh of a sucking
colt, the property of Mr. Millet, a farmer at Rockhampton, a village
near Berkeley. The inflammation continued several weeks, and at
length terminated in the formation of three or four small abscesses.
The inflamed parts were fomented, and dressings were applied by some
of the same persons who were employed in milking the cows. The number
of cows milked was twenty-four, and the whole of them had the
Cow-pox. The milkers, consisting of the farmer's wife, a man and a
maid servant, were infected by the cows. The man servant had
previously gone through the Small-pox, and felt but little of the
Cow-pox. The servant maid had some years before been infected with
the Cow-pox, and she also felt it now in a slight degree: But the
farmer's wife who never had gone through either of these diseases,
felt its effects very severely.

That the disease produced upon the cows by the colt and from thence
conveyed to those who milked them was the _true_ and not the
_spurious_ Cow-pox[5], there can be scarcely any room for suspicion;
yet it would have been more completely satisfactory, had the effects
of variolous matter been ascertained on the farmer's wife, but there
was a peculiarity in her situation which prevented my making the
experiment.

Thus far have I proceeded in an inquiry, founded, as it must appear,
on the basis of experiment; in which, however, conjecture has been
occasionally admitted in order to present to persons well situated
for such discussions, objects for a more minute investigation. In the
mean time I shall myself continue to prosecute this inquiry,
encouraged by the hope of its becoming essentially beneficial to
mankind.

  FINIS.

[Footnote 1: It is very easy to procure pus from old sores on the
heels of horses. This I have often inserted into scratches made with
a lancet, on the sound nipples of cows, and have seen no other
effects from it than simple inflammation.]

[Footnote 2: See Case IX.]

[Footnote 3: My friend Dr. Hicks, of Bristol, who during the
prevalence of this distemper was resident at Gloucester, and
Physician to the Hospital there, (where it was seen soon after its
first appearance in this country) had opportunities of making
numerous observations upon it, which it is his intention to
communicate to the Public.]

[Footnote 4: I have been informed from respectable authority that in
Ireland, although dairies abound in many parts of the Island, the
disease is entirely unknown. The reason seems obvious. The business
of the dairy is conducted by women only. Were the meanest vassal
among the men, employed there as a milker at a dairy, he would feel
his situation unpleasant beyond all endurance.]

[Footnote 5: See Note in Page 7.]




_ERRATA._


  Page 5, Line 4, after the word _shiverings_ insert _succeeded by
      heat_.
          Line 16, for _needlessly_ read _heedlessly_.

  ---- 24, Last line but one, for _sore_ read _tumour_.

  ---- 40, Line 12, for _Macklove_ read _Marklove_.

  ---- 41, Note--for _scepticus_ read _septicus_.

  ---- 60, Last line, for _moderate_ read _modern_.





     *     *     *     *     *




Transcriber's note


For this e-text, all the errors in the original book's "Errata"
section have been corrected, as well as the following:

Introductory letter: "C. H PARRY" corrected to "C. H. PARRY".

Introduction: Inserted "to" after "But this disease is not".

Case XX: "begining" corrected to "beginning".

Conclusions: Added full-stop after "on the subject of Inoculation".

The following archaic spellings of words were used in the original
book and have been retained: head-ach; concuring; delinated.