u. s. national library of
animal experimentation in
MEDICINE THROUGH 18th CENTURY
through the 18th century
National Library of Medicine
ANIMAL EXPERIMENTATION IN MEDICINE
through the l8th century
1 July - 30 October, 1965
IC/.^* NATIONAL LIBRARY OF MEDICINE
History of Medicine Division
national xmm * men*
Animal experimentation may be broadly defined as the
use of animals for the purpose of increasing knowledge of
life processes. This exhibit shows some contributions to
medical knowledge through such investigations, from
ancient times through the eighteenth century. Not all are
monuments in the history of biomedical research: included
are several lesser works. Indeed, some are shown as ex-
amples of animal experimentation which added little to
what we now consider the main lines of development, but
which were typical of their period.
During much of the classical period, the dissection
of cadavers was prohibited, and animals were used as
substitutes in the study of human anatomy. The most
important experimental animals were therefore those
thought to be most similar to humans in structure, such
as the ape, monkey, or the pig. Even these were neglected
during the early medieval period, until, with the revival
of medical education in Salerno in the 10th century,
anatomical demonstrations were again conducted with the
pig. Although the occasional dissection of human
cadavers gained sanction by the. -late ,13th century, animals
continued to serve for centuries as substitutes for the
human body as well as for experimental purposes. Thus
Blasius, as late as l673> complained in his tract on the
dog of the scarcity of human cadavers and included notes
to guide the anatomist on the structural similarities and
differences between this animal and man.
As the use of animals declined in the study and teach-
ing of gross human anatomy the emphasis turned during the
17th century to their use in comparative anatomy: Casserio,
for example, compared vocal organs of human beings and
many types of animals, including birds, mammals, fishe§,
and reptiles. During the same century the study of develop-
mental anatomy begun by the Greeks was also revived. One
of the most important contributions was De Formato Foetu
(l60k) 9 of Fabricius ab Aquapendente, who examined gravid
animals, particularly sheep, and compared the embryos to
human fetal development.
Living animals were first used for physiological
experiments in antiquity. Erasistratos (d.ca. 30h B.C.)
postulated the existence of "emanations" from living
creatures, and in what is perhaps the earliest physio-
logical experiment reported, put a bird in a container,
starved it, and noted the decrease in weight. Vivi-
section played an important role in the physiological
work of Galen, who used apes, pigs, and dogs. The revival
of such investigations in the l6th century is character-
ized by the work of Vesalius, who repeated many of Galen's
experiments on both pig ^and dog, so that the reader of
his De Humani Corporis Fabrica (15^3) could compare his
technique and findings with those of the Greek master.
The 17th century saw the real development of experiment-
al physiology in studies on circulation, respiration, and-
Unlike the more basic biomedical sciences, thera-
peutics until comparatively recent times has been based
almost entirely on experience with humans. Although
Paracelsus in the l6th century mentioned the effect of a
sulphur compound on a chicken, it was not until the l8th
century, that animals were generally used for pharmaco-
logical trials. Experimental surgery is another develop-
ment of the l8th century, although it was suggested much
earlier by Vesalius: one should undertake certain dis-
sections, he wrote, "not so much for the sake of knowledge
of the organs as iiji order to train his hands, and to learn
to sew up wounds."
While practically the entire range of the animal king-
dom has been explored, especially in the fields of com-
parative anatomy and embryology, certain animals appear
repeatedly in the annals of experimental medicine. The dog
has been used continuously almost from the beginning of
biological investigation for reasons of size, structure,
ease of handling, and economy, since it was a common ani-
mal with relatively little economic value. The chicken
plays a minor but unending role in experimental medicine.
One of the earliest identified experimental animals is a
chicken in a Hippocratic writing dating from the 6th to
3rd century B.C. A chicken was also the first recorded
subject of an experiment in hypnotism made by Kircher in
the 17th century.
With the rapid development of physiological exper-
imentation in the 17th century, the smaller animals such
as rats, mice, and rabbits figure more prominently in the
reports, although the dog continued to be the most common-
ly used. The "lower animals," such as frogs, lizards,
snakes, and salamanders, were also used extensively, for
example by Harvey during his experiments on the circula-
tion. The frog in particular became the subject of two
important early investigations, Marcello Malpighi's micro-
scopical observations of capillaries in the lung and Jan
Swammerdam's muscle-nerve preparations. The guinea pig,
which now by extension stands for any subject of experi-
mentation, was introduced into Europe from Peru in the
l6th century. Fabric ius ab Aquapendente reported on an
examination of the guinea pig as early as l6oh } but it
did not become a common experimental animal until the
The conditions of animal experimentation did not
materially change from the time of Galen until the intro-
duction of anesthesia and antiseptic surgery in the 19th
century. Here is Galen's description of his method of
preparation for a vivisection of the spinal cord, (prob-
ably in a dog or a pig):
Provide yourself with a large strong knife . . .
manufactured from exceptionally good steel ....
The animal which you vivisect should not be aged,
in order that it may prove easy for you to cut
through the vertebrae. For the bones of fully
mature animals are, on account of their hardness,
difficult to cut Lying upon its face, it
will be stretched out upon a board, the feet
being secured either by means of strong straps,
in the manner in which as you know I am accustomed
to make them fast, using a board witg holes bored
in it, or by the hands of assistants.
Scientists, then as now, have been aware that animal ex-
perimentation may cause discomfort to the subjects. In
a poem by Robert Grove, a contemporary, William Harvey is
reported to have expressed the following rationale which,
in his mind, and in the minds of many, justified such
lt is not ferocity of mind, it is not dire
lust that makes me cruel, nor is it the
mercilessness of a wicked heart; but the
sacred hunger for fame, deep within my spirit
and in my inmost "being, which forces me against
my will to make such experiments, and drives
away from my breast gentle feelings. It is in
my mind to open the dark secrets of nature, to
inquire the causes of things once unknown; to
release the truth long a captive in chains.
Ellen B. Wells
History of Medicine Division
1. Andreas Vesalius, De Humani Corporis Fabrica (Basel,
15^3), Bk. 7, Gh. 9, S. W. Lambert, trans., in
Logan Clendening, Source Book of Medical History
(New York, Hoeber, 19^2), p. lk6.
2. Galen, On Anatomical Procedures: the Later Books
(W. L. H. Duckworth, trans. , Cambridge, University
Press, 1962), p. 20.
3. S. We ir Mitchell, Some Recently Discovered Letters
of William Harvey and Other Miscellanea (Phil-
adelphia, College of Physicians, 1912), p. k-3 .
ANIMAL EXPERIMENTATION IN MEDICINE
Ancient and Medieval
1. Hippocrates. De natura pueri. IN: Hippocrates.
De genitura ... interprete Jo. Gorraeo. Paris,
Section 29 of this work, part of the Hippocratic
corpus but probably by a Cnidian writer, contains
one of the earliest suggestions for an animal ex-
periment, an embryological study, in which twenty
eggs are set for brooding and one opened each day,
providing an opportunity for observation of the
The first separately printed edition appeared in
2. Rufus of Ephesus, fl. ca. 98-H7 A.D. De corporis
humani partium appellationibus. IN: Aretaeus.
Libri septem. Venice, 1552.
In his little students' manual for learning
anatomical nomenclature, Rufus complains that in
earlier days, human dissection was permitted, and
that students "learned anatomy fearlessly and with
success." He recommends using the monkey as a
substitute, "the one which most nearly approaches
the man by the arrangement of bones, muscles, vis-
cera, veins and nerves."
This is the first printed Latin edition, translated
by G. P. Grassi.
3. Galen of Pergamon, ca. 129-199 A.D. Opera. Venice,
One of the foremost experimental physiologists of
all time, Galen's contributions were based on in-
numerable vivisections and dissections of apes and
pigs, with some use of dogs and cattle. Perhaps his
best known work concerns the nervous system, for
which he generally used pigs or goats.
This is the first printed collection of Galen 's works .
h. Anatomia porci. IN: Me sue. Me sue vita. [Leyden],
Compiled for teaching purposes at the School of
Salerno some time before 1150, it is often attri-
buted, without basis, to one Copho, a teacher
there. For the purposes of internal anatomy (human
dissection still being forbidden), the pig was used,
as "there are none so like us internally as the pig."
5. Belon, Pierre, 1517?-1564. L'histoire de la nature
des oyseaux, avec leurs descriptions. Paris, 1555*
The revival of comparative anatomy began with the
work of Belon, who dissected some two hundred
diverse species of birds, and attempted to indicate
homologous bone structures in man and bird.
Lent by the Library of Congress
6. Coiter, Volcher, 153^-1576. Externarum et internarum
principalium humani corporis partium tabulae, atque
anatomicae exercitationes observationesque.
A pupil of Gabriele Falloppio, Coiter was an early
student of comparative anatomy, restricting him-
self to skeletal structure. The principal animal
to which he compared the human skeleton was the
ape, following Galenic practice. Stimulated, per-
haps, by several cases of head injuries, he made
some experimental trephinations on dogs, birds,
7. Paracelsus, 1^93-15^1 • Opera B'ucher und Schrifften
. . . durch Joannem Huserum ... in Truck gegeben.
In his Von den naturlichen Dingen, writ tan about
1525, Paracelsus refers to what may be the earliest
recorded trial of a drug on an animal. This was a
sulphur product, which "is sweet, and liked by
chickens, in which it causes a quite harmless sleep."
8. Vesalius, Andreas, 151^-156^4-. De humani corpis
fabrica. Basle, [15^3].
The dog was chief subject of Vesalius' studies in
physiology, not only for the similarity of its in-
ternal structure to man, but also for purposes of
comparison with some of Galen's results. Vesalius,
by the time he was eighteen, had dissected and vivi-
sected many animals and was already becoming a
9- Accademia del Cimento, Florence. Essays of natural
experiments . . . Englished by Richard Waller,
Although short-lived, the Accademia, founded by
Leopold de ' Medici, was the scene of many experiments,
including animal experiments.
These essays first appeared in Italian in 1666.
10. Aselli, Gaspare, 158l-l626. De lactibus, sive lacteis
venis, quarto vasorum mesaraicorum genere, novo
invent o. Milan, 1627.
Aselli 's discovery of the lacteal vessels, took place
during a vivisection of a dog in July, 1622, which
he held originally to show some friends the func-
tion of the recurrent laryngeal nerves an operation
originally performed by Galen.
11. Blasius, Gerard, l626?-l692? Miscellanea anatomica,
hominis, brutorumque variorum. Amsterdam, 1673-
In this little manual of anatomy, Blasius discusses
the dog extensively as a substitute for the human
12. Borelli, Giovanni Alfonso, l6o8-l679« De motu
animalium. Rome, l680-l68l.
In his monumental investigations of muscular
mechanics, Borelli examined "body types and movements
of animals such as fishes, birds, and quadrupeds,
and compared them to human beings in this regard.
His approach was based on the laws of statics and
dynamics and took a mathematical bias, as might
be expected, perhaps, from a pupil of Galileo.
13- Casserio, Giulio, d. l6l6. De vocis auditusque organis
historia anatomica. Ferrara, [l60l].
Casserio examined a tremendous variety of animals in
his investigations of hearing and the production of
sound. . These were made with human anatomy in mind;
his work illustrates adult and fetal human dissec-
tions, as well as dogs, cats, rats, cattle, and even
1^-. Courten, William, 16^-2-1702. Experiments and observa-
tions of the effects of several sorts of poisons
upon animals, &c. ... Translated from the Latin ms.
Roy. Soc. Phil. Trans. 27:^85-501, 1712.
This is one of the earlier reports of trials of
various botanical poisons on dogs. Courten, a
naturalist and botanist, did his work in 1678-1679?
while studying at Montpellier.
15- Fabric ius, Hieronymus, ab Aquapendente, 1537-l6l9«
Opera omnia anatomica & physiologica. Leipzig, 1687.
The first description of the formation of the chick
in the egg since Aristotle's time is in Fabricius'
De format ione ovi et pulli, first published in 1621.
In his De formato foetu, published in 160^-, he ex-
amined mammalian fetuses in detail, with particular
attention to the sheep, and with some discussion of
fish and snakes. His public anatomies (the term
anatomy meaning dissection) attracted many viewers,
who occasionally wrote home about them. Thus we
know that on January 26, I58U, he gave a public
vivisection of a living gravid ewe, to the great
interest of those present.
16. Graaf, Reinier de, l6Ul-l673« Tractatus anatomico-
medicus de succi pancreatici natura & usu. Leyden,
De Graaf made important studies on pancreatic juice
and saliva, collecting these fluids from dogs, using
fistulas with tubes from the quills of wild ducks.
He was able to compare the pancreatic juice of the
dog with that of a sailor who had died suddenly and
reported that they had identical properties.
This work was first published in 166k.
17. Grew, Nehemiah, 16^-1-1712. The comparative anatomy of
stomachs and guts begun. London, l68l. Reissued
with his Musaeum Regalis Societatis. London, 169^ •
Although best known, perhaps, as a plant morphologist
and microscopist , Grew used man as a common de-
nominator in comparing the same set of organs in a
wide range of animals. He emphasized the necessity
of understanding the functions of the organs in
order to make valid comparisons.
18. Harvey, William, 1578-1657* Exercitatio anatomica de
motu cordis et sanguinis in animalibus. Frankfurt,
In the course of his investigations on the circula-
tion of the blood, Harvey used forty-nine varieties
of animals, and these formed the basis for his con-
19. Kircher, Athanasius, 1602-1680. Ars magna lucis et
umbrae . Rome ,
A chicken was used in the first recorded experiment
in hypnotism, part of a series in one of Kircher' s
works on perception and color theory. He called the
hypnotic state " act inovoli sinus," or"brilliant
20. Malpighi, Marcello, 1628-1694. Opera omnia.
Malpighi' s observation of capillaries in a frog's
lung was the first use of the microscope with sig-
nificant scientific results, in this case verifying
what Harvey had postulated but not seen thirty- two
His letter to Borelli on this subject was first pub-
lished in l66l, as De pulmonibus. Observationes
21. Nuck, Anton, 165O-I692. Adenographia curiosa et
uteri foeminei anatome nova. Leyden, 1691.
There were many theories of mammalian generation,
but very few experiments to test them. Anton Nuck,
a professor of anatomy at Leyden made one. He open-
ed a female dog three days after copulation?. ligated
the uterine horn, and observed pregnancy afterwards,
above the ligature. He wrongly concluded that the
embryo had been derived from the ovary without
22. Pecquet, Jean, 1622-167^ • Experimenta nova anatomica.
IN: Munier, J. A. De venis tarn lacteis thoracicis.
While studying at Montpellier in l6*+7, Pecquet, in
the course of dissecting dogs, worked out the trans-
mission route of chyle from the cisterna chyli
through the lacteal vessels into the venous system.
This work was first published in 1651.
23. Redi, Francesco, 1626-1698. Esperienze intorno alia
generazione degl' insetti. Florence, 167^.
Redi's use of insects in a "control experiment" in-
volved two sets of jars containing meat, one open t'
other with gauze oyer the tops. In time, maggots
appeared within the open jars, but on the gauze cove-
ing the others, proving that worms did not arise
spontaneously in rotting meat.
2h. Severino, Marco Aurelio, I58O-I656. Zootomia Democri-
taea; id est, Anatome generalis totius animantium
opificii. Nuremberg, I6U5.
In this, the earliest comprehensive treatise on com-
parative anatomy, Severino tried to trace analogies
of construction in corresponding parts of various
animals. He included the text of the Anatomia porci
(the last time it was printed as a practical work) ,
and also wrote a section on the qualifications of an
anatomist, including ambidexterity and ability to
use the microscope. The anatomist, he wrote, must
not abominate the human body, and must be ready to
explore, with his own hands, the secrets of living
25. Steno, Nicolaus, Bp., 1638-1686. Observationes anato-
micae. Leyden, 1662.
This includes Steno' s account of his discovery of the
parotid gland while he was studying at the home of
Blasius in 1660. He was dissecting the head of a
sheep, and found the duct when his dissecting tool
slipped through the gland and clinked against the
26. Swammerdam, Jan, 1637-1680. Tractatus physico-anato-
nico-medicus de respiratione usuque pulmonum. Leyden,
In a very involved and quite modern series of ex-
periments, Swammerdam used dogs to demonstrate the
movements involved in breathing. It is a classic
27. Walaeus, Johannes, l6oU-l649« Deux lettres ... du
mouvement du chyle et du sang. IN: Bartholin, C.
Institutions anatomiques. Paris, I6U7.
Although at first opposed to Harvey's view of the
circulation, Walaeus changed his opinion after ex-
perimenting on a dog and demonstrating to his own
satisfaction the direction of blood flow in veins.
His letter was first published in l6kl.
28. Zambeccari, Giuseppe, 1653-1728. Esperienze ... in-
torno a diverse viscere tagliate a diversi animali
viventi. Florence, 1680.
A pupil of Redi and a pioneer in experimental
surgery, Zambeccari performed experimental ex-
cisions of various internal organs on dogs and
an occasional chicken. One dog survived four con-
29. Abernethy, John, 1764-1831. Surgical and physiologi-
cal essays. London, 1793.
Abernethy appears to have performed some of the
earliest, nutrition experiments, desiring to introduce
his course of anatomical lectures "with a philo-
sophical account of the nature of the matter, which
composes an animal body. " He fed a rabbit with
lettuce he had grown on flannel and distilled water,
and observed that the rabbit rapidly declined.
30. Adams, George, d. 1773- Micrographia illustrata.
This served as a kind of laboratory manual for the
many naturalists, biologists, and diletantes who
were beginning to collect, observe, and experiment,
as well as for anatomists and physiologists. Among
the apparatus illustrated is a handy rack for
stretching frog preparations.
31. Beddoes, Thomas, I76O-I808, and James Watt, 1736-1819.
Considerations on the medicinal use and on the pro-
duction of factitious airs. 2d ed. Bristol, 1795.
In the process of developing what became pneumo-
therapy, Beddoes used puppies, kittens, and rabbits
to test the various airs and atmospheres created
in James Watts' newly constructed apparatus.
32. Crawford, Adair, 17^8-1795. Experiments and ob-
servations on animal heat. 2d ed. London, 1788.
Une of the earliest uses of guinea pigs was in
the summer of 1777, when Crawford began his care-
ful investigations of animal heat. His method
involved water calorimetry.
Douglas, Sylvester, I7U3-I823. Dissertatio medica
inauguralis de stimulis. Leyden, 1766.
This student dissertation is a rambling discourse
on stimulation and movement, following the lead
of Haller and Whytt. The author performed several
experiments, using as subjects six rabbits, two
sheep and one dog.
Fontana, Felix, 1730-1805. Treatise on the venom of
the viper. London, 1787*
Fontana, naturalist to the Grand Duke of Tuscany,
used guinea pigs, frogs, and rabbits. He tested
the effects of viper venom on various bodily fluids
and tissues, for example blood, tendons, and nerves,
and often used controls.
This work was first published in 17^7 •
Galvani, Luigi, 1737-1798* viribus electricitatis
in motu musculari. Modena, 1792.
The frog was the chief subject in Galvani's studies
of electrical phenomena in organisms.
Hales, Stephen, l6 77-1761. Statical essays: contain-
ing haemastaticks. Vol. II. London, 1733*
An English clergyman, and an amateur in science,
Hales made important contributions to the understand-
ing of the mechanics of blood pressure. Using several
horses, he measured the bood pressure by means of
tubes inserted in an artery. He also used dogs and
other animals. The horses, Hales tells us, were all
unfit for service and would in any case have been
Haller, Albrecht von, 1708-1777- A dissertation on
the sensible and irritable parts of animals. Trans-
lated from the Latin ... by M. Tissot. London, 1755.
The multitudinous contributions of Haller, one of
the greatest physiologists of all time, include
a series of experiments made in Gbttingen in the
early 1750 's, in which he distinguished between
nerve impulse and muscle contraction. For these
experiments, he used dogs and goats, as well as
rats, cats, and rabbits.
Haller, like Harvey, felt sympathy for his subjects:
. . . and since the beginning of the year 1751
I have examined several different ways, a
hundred and ninety animals, a species of cruelty
for which I felt such a reluctance, as could
only be overcome by the desire of contributing
to the benefit of mankind, and excused by that
motive which induces persons of the most humane
temper, to eat every day the flesh of harmless
animals without scruple.
His memoir on these experiments was originally read
in the Academy at Gbttingen in April, 1752.
Home, Evrard, 1756-1832. An account of Mr. Hunter's
method of performing the operation for the cure of
the poplitean aneurism. Soc. for the Improvement
of Med. and Chir. Knowledge. Trans. I:138-l8l,
Based on his experiments with Richmond Park deer
and with dogs, John Hunter (1728-1793) developed an
improved method of tying off aneurysms.
Kite, Charles, d. l8ll. Essays and observations,
physiological and medical, on the submersion of
animals. London, 1795*
In 1788, Kite, a medical writer and practitioner at
Gravesend, won the silver medal from the Humane Soci
for his work on recovery of the apparently dead. He
continued his investigations on various aspects of
drowning, using cats and dogs.
ho. Leigh, John, fl. 1785. An experimental inquiry into
the properties of opium, and its effects on living
subjects. Edinburgh, 1786.
While in Edinburgh, John Leigh of Virginia produced
this careful, critical study of opium, testing its
qualities oh dogs and rabbits. It did not really
add anything new, but was typical of the dawning
style of experimental inquiry.
His work is dedicated to George Washington, "a man
equally revered by the friends and foes of his
^-1. Monro, Alexander, 1733-l8l7« Experiments on the nerv-
ous system, with opium and metalline substances.
On the basis of his experiments with the effect of
opium on the tissues of frogs, Monro concluded
that nerve force was not equal to electrical force.
By this time, the frog had become a relatively
common experimental animal.
h2. Murray, Andreas Johann Georg, 17^0-1791 • Commentatio
de redintegratione partium corporis animalis nexu
suo solutarum vel amissarum. Gbttingen, 1787*
The restoration of injured tissue was the subject of
a debate which took place before the medical faculty
of Gbttingen in June of 1787- Murray, a naturalist,
contended that most tissue could not be made to
restore itself and gave as proof copius literature
citations and records of his experiments on 17 dogs,
h rabbits, and 1 chicken. He was able, in one case,
to replace part of a tendon with a ligament.
U3. Priestley, Joseph, 1733-180^. Experiments and observ-
ations on different kinds of air. 2d ed. corr.
Priestley used rats and mice when proving the
necessity of oxygen to the maintenance of life.
He included in his introduction to the work shown
some comments on the capture and care of his labora-
kk. Smith, Thomas, fl. 1805. An essay on wounds of the in-
testines [an inaugural essay . . . University of
Pennsylvania] Philadelphia, 1805.
In a rather unusual thesis, Smith, a student from the
island of St. Croix, tried various stitching tech-
niques on dogs, in an attempt to improve intestinal
wound repair. Of the eleven dogs used, six survived
and were later sacrificed for evaluations of the
h^. Spallanzani, Lazzaro, 1729-1799. An essay on animal
reproductions . . . Translated [by M. Mary] London,
Confining himself to snails, salamanders, frogs, and
worms, Spallanzani conducted a series of experiments
on tissue regeneration and recorded microscopic
observations of the reforming tissue. A man of
great experimental skill, he also did important work
on digestion and generation.
This work was originally published in Modena in 1768,
as Prodromo di un opera da imprimersi sopra le
U6. Stevens, Edward W. , fl. 1777. Dissertatio physio-
logica inauguralis, de alimentorum concoct ione.
In his digestion experiments, Stevens used small
perforated silver spheres, in which various types of
food were placed. These were swallowed by dogs,
sheep, and cattle, and by one man "of weak under-
standing who swallowed stones for the amusement of
the common people." Stevens concluded, as did
Spallanzani at about the same time, that digestion
was not accomplished by heat, putrefaction, or fer-
mentation, but by a "solvent" secreted by the stomach.
h7- Sue, Jean- Joseph, I76O-I83O. Recherches physiologi-
ques, et experiences sur la vitality. Paris, An
Opposed to the use of the guillotine on the grounds
that the parts severed might continue to live for
some time and have sensations, Sue conducted trial
decollations on chickens, frogs, rabbits, and
cattle to prove his point. He also stated clearly
that animal experimentation had valid meaning for
h8. Townson, Robert, fl. 1792-1799- Tracts and observa-
tions in natural history and physiology. London,
The studies on. amphibian anatomy and physiology
in this work were originally made by Townson in
Gbttingen for his medical degree, granted in
1795* It may have had some value as a laboratory
^9. Trembley, Abraham, 1710-178^. Memoires, pour servir
a 1'histoire d* un genre de polypes d'eau douce.
The first view of cell division was seen in a hydra,
by Trembley, using a hand lens. He was also the
first to make permanent grafts of animal tissue,
again using the hydra (discovered some 39 years
before by Leeuwenhoek) , and thus laying the ground-
work for experimental morphology.
50. [Whytt, Robert] 171^-1766. An essay on the vital and
other invo.intary motions of animals. 2d ed. , with
corr. and add. Edinburgh, 1763*
Probably the foremost neurologist of his time,
Whytt, on the basis of his experiments on decap-
itated frogs, birds, some eels, and a snake,
suggested that the soul was equally distributed
throughout the nervous system. He investigated re-
flex action as well.
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