On the Heart, or De
Corde trans. by I.M. Lonie in Lloyd, G.E.R., Hippocratic Writings.
London: Penguin Books, 1978, pp. 347-351, ch. 11.
11. Its nutriment is neither the solid food nor the drink which comes from the
belly, but a pure and luminous substance which is refined out of the blood. It
conveys this nutriment out of the neighbouring blood receptacle by transmitting
its rays, deriving it from there as though from the belly and intestines, which
of course it does not do in reality. Now to avoid any disturbance form the
confused movement of the food in the great artery [i.e. the aorta], it closes
off the passage to that artery. For the great artery feeds from the belly and
intestines and is laden with food not fit for the ruling principle.
It is obvious that the left cavity is not nourished by visible blood: if
you kill an animal by cutting its throat and open up the left chamber, you will
find it quite empty apart from some serum and bile, and the membranes which I
have described. But he artery will not be empty of blood, nor the right
chamber. This, then, as I see it, is the reason for the membranes on this
vessel.