ANQIOLOGIA. 



VASCULAR SYSTEM. 



" In the history of Physiology, I have shown that those who studied the 

 structure of animals were irresistibly led to the conviction that the parts of 

 this structure have each its end or purpose ; that each member and organ 

 not merely produces a certain effect or answers a certain use, but is so 

 framed as to impress us with the persuasion that it was constructed for that 

 use ; that it was intended to produce the effect. It was there seen that this 

 persuasion was repeatedly expressed in the most emphatic manner by Galen ; 

 that it directed the researches and led to the discoveries of Harvey ; that it 

 has always been dwelt upon as a favourite contemplation, and followed as a 

 certain guide by the best anatomists ; and that it is inculcated by the physio- 

 logists of the profoundest views and most extensive knowledge of our own 

 time. All these persons have deemed it a most certain and important prin- 

 ciple of physiology, that in every organized structure, plant, or animal, each 

 intelligible part has its allotted office ; each organ is designed for its ap- 

 propriate function ; that nature, in these cases, produces nothing in vain ; 

 that, in short, each portion of the whole arrangemen thas its final cause ; an 

 end to which it is adapted, and in this end the reason that it is where and 

 what it is." WHEWELL. Indications of the Creator, p. 75. 



