82 



The Relation of the Kidneys to Metabolism, 



of Eose Bradford ; and it may be pointed out that the effect, even in dogs, is 

 not a constant one, since in half of Bradford's experiments the urine was no 

 more abundant after the second than after the first operation. 



It may be concluded, therefore, that the increase in quantity and decrease 

 in concentration of dog's urine, after operations on the kidneys, is an 

 incidental rather than an essential result. 



Table III. 





Nature of food. 



Urine. 



Amount. 



Sp. gr. 



Total N. 



Normal cat 



After first operation — 



fMeat 



\ Bread and milk . . . 



("Meat 



c.c. 

 112 

 310 



128 

 435 

 164 



1046 

 1007 



1040 

 1005 

 1038 



grammes. 

 5-4 

 1-6 



5-1 

 1-55 

 3-44 

 2-1 



2-65 



? 



1-49 

 3-02 

 0-94 

 1-07 

 1-10 

 2-44 



Cat I 



\ Bread and milk . . . 

 J Meat 



Cat II 



CatHI 



Cat IV 



\Milk 



Meat and milk . . . 

 Meat 



124 1020 

 68 1042 



110 1040 

 43 1054 





f Meat 



Cat V 



[Milk 



150 



. 90 

 182 

 J 78 

 I 81 

 J 100 

 \ 208 



1015 



1020 

 1018 

 1030 

 1018 

 1019 



After second operation — 



/Milk 



Cat I 



\ Meat 



Cat II 



CatHI 



Milk 



Meat and milk ... 





1018 



Conclusions. 



1. We confirm Bradford's observations that removal of three-quarters or 

 more of the total kidney weight in cats is followed by loss of appetite, wasting, 

 and death within a few days or weeks. 



2. We find that in such cats an increased output of nitrogen is not of 

 constant occurrence ; and that it takes place only in cats which have lost 

 22 per cent, or more of their initial body weight at the time of its onset. 



3. We conclude, therefore, that the kidneys have no direct influence upon 

 nitrogenous metabolism, and that the increased output of nitrogen is simply 

 the result of inanition, and is of the same nature as that observed in starving 

 animals. 



4. We find that, after removal of a portion of one kidney, and also after 

 subsequent removal of the opposite kidney, cats are still able to pass a 

 concentrated urine, and that the amount of the urine is not necessarily 

 increased beyond the normal. 



