8
We have, moreover, direct personal evidence to
his studies in this direction; for Aubrey found
him reading Oughtred's Clavis Mathematica, and
working the problems when he was no longer a
young man. Now his strongest and most irre-
fragable argument for the new view of the circu-
lation is distinctly numerical. "Supponamus," he
says, "quantum sanguinis sinister ventriculus in
dilatatione quum repletus sit contineat, sive zij;
sive Zjss; ego in mortuo reperi ultra žij;" and
further on the problem thus concisely proposed is
continued:
"Ita in homine protrudi singulis cordis pulsibus, suppo- namus unciam semis, vel drachmas iij, vel drachmam unam sanguinis, qui propter impedimentum valvularum in cor re- meare non potest. Cor unâ semihorâ plus quam mille pulsus facit. Jam mutiplicatis drachmis videbis unâ semi- horâ, aut millies drachmas tres, vel drachmas duas aut uncias quinquies centum, per cor in arterias transfusam, quæ ma- jor est copia quam in universo corpore contingat reperiri. Quare concludendum si unciam transmissam contingere, libras 83 et Siv in unâ semihorâ transfusas esse de venis in arterias.
He saw distinctly that the heart was simply a double force-pump, propelling an incompressible fluid into an equally double system of tubes; that
