Abstract

Mr. Powell's ingenious observations on The Simile of the Clepsydra in Empedocles raise afresh the problem of the precise form and construction of the instrument with whose aid Empedokles is said to have reached his memorable conclusion that air is a corporeal substance. That ‘klepsydra’ was the name of the instrument in question is shown by a comparison of Aristotle, Phys. 213a, 22 sqq. with Empedokles, fr. 100; but though so far the fragment is plain, in its detailed interpretation there arises a difficulty which is the subject of the present note. Empedokles is explaining his theory of respiration, and the theory is illustrated by the action of this apparatus. To make clear the general drift of the passage, it may be well to quote again so much of it as is relevant. ‘Thus do all things draw breath in and breathe it out again. All have bloodless tubes of flesh extended over the surface of their bodies; and at the mouths of these the outermost surface of the skin is perforated all over with pores closely packed together, so as to keep in the blood while a free passage is cut for the air to pass through. Then, when the thin blood recedes from these, the bubbling air rushes in with an impetuous surge; and when the blood rushes back it’ ‘is breathed out again.