Page:The Harveian oration, 1875 (IA b22314611).pdf/22

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if the ventricle be pierced, the blood spurts out each time the heart moves, and grows tense; and, when the heart as a whole has ceased to beat, but the auricles still contract, if the finger be placed on the ventricles, each contraction is felt as a pulse, and, if the point of the heart be cut off with a pair of scissors, blood flows with each beat.

Putting together all his many observations and experiments on this division of his subject, Harvey concluded that the heart moves in two times and four places; that the auricles first contract together, then the ventricles; and that (speaking of the ventricles alone as the heart) these things happen in our bodies at the same instant: the tension of the heart, the pulse at its apex, felt striking against the ribs; the thickening of its walls; and the forcible expulsion of the blood it contains by the contraction of the ventricles.

Harvey has completely mastered the heart's motions. He knows all about them, as well as we do now; and, in discovering the truth, sweeps away these errors; —that the heart dilating, draws blood into its ventricles; that when it strikes the breast, its ventricles are distended with blood; that its fibres contract (as Yesalius thought they did)

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