Caspar Bauhin and John Riolan, [Footnote: i Bauhin, lib. ii. cap.
II. Riolan. lib. viii, cap. I.] most learned men and skilful
anatomists, inform us that from their observations, that if we
carefully watch the movements of the heart in the vivisection of
an animal, we shall perceive four motions distinct in time and in
place, two of which are proper to the auricles, two to the
ventricles. With all deference to such authority I say that there
are four motions distinct in point of place, but not of time; for
the two auricles move together, and so also do the two
ventricles, in such wise that though the places be four, the
times are only two. And this occurs in the following manner:
There are, as it were, two motions going on together: one of the
auricles, another of the ventricles; these by no means taking
place simultaneously, but the motion of the auricles preceding,
that of the heart following; the motion appearing to begin from
the auricles and to extend to the ventricles. When all things are
becoming languid, and the heart is dying, as also in fishes and
the colder blooded animals there is a short pause between these
two motions, so that the heart aroused, as it were, appears to
respond to the motion, now more quickly, now more tardily; and at
length, when near to death, it ceases to respond by its proper
motion, but seems, as it were, to nod the head, and is so
slightly moved that it appears rather to give signs of motion to
the pulsating auricles than actually to move. The heart,
therefore, ceases to pulsate sooner than the auricles, so that
the auricles have been said to outlive it, the left ventricle
ceasing to pulsate first of all; then its auricle, next the right
ventricle; and, finally, all the other parts being at rest and
dead, as Galen long since observed, the right auricle still
continues to beat; life, therefore, appears to linger longest in
the right auricle. Whilst the heart is gradually dying, it is
sometimes seen to reply, after two or three contractions of the
auricles, roused as it were to action, and making a single
pulsation, slowly, unwillingly, and with an effort.
But this especially is to be noted, that after the heart has
ceased to beat, the auricles however still contracting, a finger
placed upon the ventricles perceives the several pulsations of
the auricles, precisely in the same way and for the same reason,
as we have said, that the pulses of the ventricles are felt in
the arteries, to wit, the distension produced by the jet of
blood. And if at this time, the auricles alone pulsating, the
point of the heart be cut off with a pair of scissors, you will
perceive the blood flowing out upon each contraction of the
auricles. Whence it is manifest that the blood enters the
ventricles, not by any attraction or dilatation of the heart, but
by being thrown into them by the pulses of the auricles.
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Elsewhere in the archive
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account