146 ON THE NATURE AND PRINCIPLES OF 



allowed me to satisfy myself, by deliberate reflection, 

 of the accuracy of my original impressions, but has 

 also enabled me to investigate some important points 

 in the physiology of the circulation, and thus, I trust, 

 given greater clearness and comprehensiveness to my 

 views on the local derangements of that great in- 

 strument of animal life. 



It will thus be seen that these researches were 

 not, in the first instance, directed to the attainment 

 of any higher object than the settlement of some 

 points connected with the morbid appearances and 

 effects of nephritis. And it was their success in 

 illustrating the mode of production of certain pheno- 

 mena of this particular affection which encouraged 

 me to extend my observations, in the hope of 

 obtaining results applicable to the elucidation of the 

 general subject of inflammation. Another important 

 inducement to persevere in this extended inquiry 

 arose from the conviction that no other organ in the 

 body presents equal facilities with the kidney for an 

 experimental investigation of this nature. In any 

 of the lower animals, this gland, particularly that of 

 the left side, can be readily reached and exposed by 

 an incision in the loins, passing between the lumbar 

 and abdominal muscles. And, as its connections 

 with the surrounding structures are very slight, it 

 can, if required, be drawn out through the wound, 

 its vessels and duct isolated, and, if necessary, 

 secured by ligature ; and the organ then returned 

 without the infliction of any material injury to it or 

 any other vital structure. Then its blood-vessels 

 are so arranged that, while both vein and artery arc 



