BOOK TWO

 [p. 121] indefinite distance, and if, therefore, there is need of some other mechanism to explain why the blood is conveyed in all directions, then the principle of the refilling of a vacuum may be looked on as a necessary addition;

A certain subordinate place allowed to the horror vacui.

there will not, however, be a plethora in any of the parts coming after the liver,

i.e. the parts to which the veins convey blood after it leaves the liver - second stage of anadosis; cf. p. 91, note 2; p. 13, note 5.

or, if there be, it will be in the region of the heart and lungs; for the heart alone of the parts which come after the liver draws the nutriment into its right ventricle, thereafter sending it through the arterioid vein

What we now call the pulmonary artery. Galen believed that the right ventricle existed for the purpose of sending nutrient blood to the lungs.

to the lungs (for Erasistratus himself will have it that, owing to the membranous excrescences,

Lit. owing to the ongrowth (epiphysis) of membranes; he means the tricuspid valve; cf. p. 314, note 2; p. 321, note 4.

no other parts save the lungs receive nourishment from the heart). If, however, in order to explain how plethora comes about, we suppose the force of compression by the stomach to persist indefinitely, we have no further need of the principle of the refilling of a vacuum, especially if we assume contraction of the veins in addition- as is, again, agreeable to Erasistratus himself.

PART 2

Let me draw his attention, then, once again, even if he does not wish it, to the kidneys, and let me state that these confute in the very clearest manner such people as object to the principle of attraction. Nobody has ever said anything plausible, nor, as we previously showed, has anyone been able to discover,