Introduction 21 



Laurentius boasts that he had predicted the cause of 

 the symptoms. For my own part, however, I cannot 

 but wonder, since he had divined and predicted that 

 heterogeneous matter could be discharged by the course 

 he indicates, why he could not or would not perceive,, 

 and inform us that, in the natural state of things, the 

 blood might be commodiously transferred from the lungs 

 to the left ventricle of the heart by the very same route. 

 Since, therefore, from the foregoing considerations 

 and many others to the same effect, it is plain that what 

 has heretofore been said concerning the motion and 

 function of the heart and arteries must appear obscure, 

 or inconsistent or even impossible to him who carefully 

 considers the entire subject ; it will be proper to look 

 more narrowly into the matter ; to contemplate the 

 motion of the heart and arteries, not only in man, but 

 in all animals that have hearts ; and further, by frequent 

 appeals to vivisection, and constant ocular inspection, 

 to investigate and endeavour to find the truth. 



