130 WILLIAM HARVEY 



parts as from a fountain head; from which sustenance may 

 be derived; and upon which concoction and nutrition, and 

 all vegetative energy may depend. Now, that the heart is 

 this place, that the heart is the principle of life, and that all 

 passes in the manner just mentioned, I trust no one will 

 deny. 



The blood, therefore, required to have motion, and indeed 

 such a motion that it should return again to the heart; for 

 sent to the external parts of the body far from its fountain, 

 as Aristotle says, and without motion, it would become con- 

 gealed. For we see motion generating and keeping up heat 

 and spirits under all circumstances, and rest allowing them 

 to escape and be dissipated. The blood, therefore, becoming 

 thick or congealed by the cold of the extreme and outward 

 parts, and robbed of its spirits, just as it is in the dead, it 

 was imperative that from its fount and origin, it should 

 again receive heat and spirits, and all else requisite to its 

 preservation that, by returning, it should be renovated and 

 restored. 



We frequently see how the extremities are chilled by the 

 external cold, how the nose and cheeks and hands look blue, 

 and how the blood, stagnating in them as in the pendent or 

 lower parts of a corpse, becomes of a dusky hue ; the limbs 

 at the same time getting torpid, so that they can scarcely be 

 moved, and seem almost to have lost their vitality. Now 

 they can by no means be so effectually, and especially so 

 speedily, restored to heat and colour and life, as by a new 

 efflux and contact of heat from its source. But how can 

 parts attract in which the heat and life are almost ex- 

 tinct? Or how should they whose passages are filled with 

 condensed and frigid blood, admit fresh aliment renovated 

 blood unless they had first got rid of their old contents? 

 Unless the heart were truly that fountain where life and 

 heat are restored to the refrigerated fluid, and whence 

 new blood, warm, imbued with spirits, being sent out by 

 the arteries, that which has become cooled and effete is 

 forced on, and all the particles recover their heat which 

 was failing, and their vital stimulus wellnigh exhausted. 



Hence it is that if the heart be unaffected, life and health 

 may be restored to almost all the other parts of the body; 





