so much in those places which are farther off. Next, the hardnesse
of the skin of which the artery vein and the great artery are composed,
sheweth sufficiently, that the bloud beats against them more forcibly
then against the veins. And why should the left concavity of the heart,
and the great artery be more large and ample then the right concavity,
and the arterious vein; unless it were that the bloud of the veinous
artery, having bin but onely in the lungs since its passage thorow the
heart, is more subtil, and is rarified with more force and ease then the
bloud which immediately comes from the _vena cava_. And what can the
Physicians divine by feeling of the pulse, unlesse they know, that
according as the bloud changeth its nature, it may by the heat of the
heart be rarified to be more or lesse strong, and more or lesse quick
then before. And if we examine how this heat is communicated to the
other members, must we not avow that 'tis by means of the bloud, which
passing the heart, reheats it self there, and thence disperseth it self
thorow the whole body: whence it happens, that if you take away the
bloud from any part, the heat by the same means also is taken a way. And
although the heart were as burning as hot iron, it were not sufficient
to warm the feet and the hands so often as it doth, did it not continue
to furnish them with new bloud.

Besides, from thence we know also that the true use of respiration is to
bring fresh air enough to the lungs, to cause that bloud which comes
from the right concavity of the heart, where it was rarified, and (as it
were) chang'd into vapours, there to thicken, and convert it self into
bloud again, before it fall again into the left, without which it would
not be fit to serve for the nourishment of the fire which is there.
Which is confirm'd, for that its seen, that animals which have no lungs
have but one onely concavity in the heart; and that children, who can
make no use of them when they are in their mothers bellies, have an
opening, by which the bloud of the _vena cava_ runs to the left
concavity of the heart, and a conduit by which it comes from the
arterious vein into the great artery without passing the lungs.

Next, How would the concoction be made in the stomach, unlesse the heart
sent heat by the arteries, and therewithall some of the most fluid parts
of the bloud, which help to dissolve the meat receiv'd therein? and is
not the act which converts the juice of these m