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1886。＇26＇
＇26＇ William Harvey： Prelectiones Anatomiae Universalis； London； J。
& A。 Churchill； 1886。
The second day lecture； April 17； was concerned with a description of
the organs of the thorax； and after a discussion on the structure and action
of the heart come the lines：
W。 H。 constat per fabricam cordis sanguinem per pulmones in Aortam
perpetuo transferri； as by two clacks of a water bellows to rayse water
constat per ligaturam transitum sanguinis ab arteriis ad venas unde
perpetuum sanguinis motum in circulo fieri pulsu cordis。
The illustration will give one an idea of the extraordinarily crabbed
hand in which the notes are written； but it is worth while to see the original；
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for here is the first occasion upon which is laid down in clear and
unequivocal words that the blood CIRCULATES。 The lecture gave
evidence of a skilled anatomist； well versed in the literature from Aristotle
to Fabricius。 In the MS。 of the thorax； or； as he calls it； the 〃parlour〃
lecture； there are about a hundred references to some twenty authors。 The
remarkable thing is that although those lectures were repeated year by year；
we have no evidence that they made any impression upon Harvey's
contemporaries； so far； at least； as to excite discussions that led to
publication。 It was not until twelve years later； 1628； that Harvey
published in Frankfurt a small quarto volume of seventy…four pages；＇27＇
〃De Motu Cordis。〃 In comparison with the sumptuous 〃Fabrica〃 of
Vesalius this is a trifling booklet； but if not its equal in bulk or
typographical beauty （it is in fact very poorly printed）； it is its counterpart
in physiology； and did for that science what Vesalius had done for anatomy；
though not in the same way。 The experimental spirit was abroad in the
land； and as a student at Padua； Harvey must have had many opportunities
of learning the technique of vivisection； but no one before his day had
attempted an elaborate piece of experimental work deliberately planned to
solve a problem relating to the most important single function of the body。
Herein lies the special merit of his work； from every page of which there
breathes the modern spirit。 To him； as to Vesalius before him； the current
views of the movements of the blood were unsatisfactory； more
particularly the movements of the heart and arteries； which were regarded
as an active expansion by which they were filled with blood； like bellows
with air。 The question of the transmission of blood through the thick
septum and the transference of air and blood from the lungs to the heart
were secrets which he was desirous of searching out by means of
experiment。
＇27＇ Harvey： Exercitatio Anatomica de Motu Cordis et Sanguinis in
Animalibus； Francofurti； 1628。
One or two special points in the work may be referred to as
illustrating his method。 He undertook first the movements of the heart； a
task so truly arduous and so full of difficulties that he was almost tempted
to think with Fracastorius that 〃the movement of the heart was only to be
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comprehended by God。〃 But after many difficulties he made the following
statements： first； that the heart is erected and raises itself up into an apex；
and at this time strikes against the breast and the pulse is felt externally；
secondly； that it is contracted every…way； but more so at the sides； and
thirdly； that grasped in the hand it was felt to become harder at the time of
its motion； from all of which actions Harvey drew the very natural
conclusion that the activity of the heart consisted in a contraction of its
fibres by which it expelled the blood from the ventricles。 These were the
first four fundamental facts which really opened the way for the discovery
of the circulation； as it did away with the belief that the heart in its motion
attracts blood into the ventricles； stating on the contrary that by its
contraction it expelled the blood and only received it during its period of
repose or relaxation。 Then he proceeded to study the action of the arteries
and showed that their period of diastole； or expansion； corresponded with
the systole； or contraction； of the heart； and that the arterial pulse follows
the force； frequency and rhythm of the ventricle and is； in fact； dependent
upon it。 Here was another new fact： that the pulsation in the arteries was
nothing else than the impulse of the blood within them。 Chapter IV； in
which he describes the movements of the auricles and ventricles； is a
model of accurate description； to which little has since been added。 It is
interesting to note that he mentions what is probably auricular fibrillation。
He says： 〃After the heart had ceased pulsating an undulation or palpitation
remained in the blood itself which was contained in the right auricle； this
being observed so long as it was imbued with heat and spirit。〃 He
recognized too the importance of the auricles as the first to move and the
last to die。 The accuracy and vividness of Harvey's description of the
motion of the heart have been appreciated by generations of physiologists。
Having grasped this first essential fact； that the heart was an organ for the
propulsion of blood； he takes up in Chapters VI and VII the question of the
conveyance of the blood from the right side of the heart to the left。 Galen
had already insisted that some blood passed from the right ventricle to the
lungsenough for their nutrition； but Harvey points out； with Colombo；
that from the arrangement of the valves there could be no other view than
that with each impulse of the heart blood passes from the right ventricle to
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the lungs and so to the left side of the heart。 How it passed through the
lungs was a problem： probably by a continuous transudation。 In Chapters
VIII and IX he deals with the amount of blood passing through the hear