32 EXPERIMENTS ON THE CIRCULATION 



milar changes. An extended investigation of the 

 changes which kidneys thus treated would finally 

 undergo could not fail to throw important light on 

 some of the secondary effects of inflammation. 



I shall now pass on to the second class of experi- 

 ments, or those intended to illustrate the effects of 

 an increased determination of blood to the vessels of 

 a part previously healthy. 



It occurred to me, that if an increased flow of 

 blood could be suddenly directed through any parti- 

 cular artery, the contractility of the smaller vessels 

 would resist the rapid dilatation necessary for the 

 free passage of the augmented quantity of fluid, and 

 thus give rise to some obstruction. If any obstruc- 

 tion did take place, then both the conditions re- 

 quired to produce undue compression of the blood 

 would co-exist, and some of its effects should be 

 perceptible in the urine. 



CLASS II. 



A. I first attempted to accomplish this end in 

 the case of the renal artery by removing one kidney, 

 thinking that the physiological determination to the 

 other might suffice. I repeated the experiment five 

 times, chiefly in young and weak animals. The only 

 constant result observed was a progressive inorea-r 

 in the weight of the remaining kidney. In one 



