VIII 



AN EPITOME AND ESTIMATE OF HARVEY'S 



WORK 



(a) THE PRELIMINARY OBSERVATIONS 



IN summarising this great work we shall try to avoid 

 its difficulties. Sometimes we shall give Harvey's con- 

 clusions in our own words, sometimes in his. His 

 antiquated references we shall mainly omit. At times 

 we shall rearrange his subject. It will be best to classify 

 his material into a series of sections, w r hich do not always 

 correspond to his chapters. Each of these sections 

 leads to a conclusion, but they will differ greatly in 

 length according to the amount of material to be con- 

 sidered or the difficulty of understanding the point with 

 which each deals. 



1. "If the heart is grasped in the hand, it may be felt 

 to become harder during its action. This hardness 

 proceeds from tension, just as when the forearm is 

 grasped, its muscles are perceived to become tense and 

 firm when [these muscles] move the fingers." 



The contraction or systole of the heart therefore 

 corresponds to its active position ; its expansion or 

 diastole corresponds to its position of rest. 



2. 'It may further be observed in fishes and cold- 

 blooded animals [in which the heart beats long after 

 the death of the animal] . . . that when the heart moves 

 it becomes of a lighter colour, and when it is quiescent 



