ANALYSES OF URl-NE OF DIFFERENT ANIMALS* 



Urine of the 

 lion and tiger. 



Points in 



which they 

 differ from 

 that of man. 



Ammonia. 



No uric acid 



animal food 

 therefore not 

 its source. 



Want of phos- 

 phate of lime. 



Yet this is se- 

 parated in the 

 kidneys ; 

 but prohably 

 precipitated 

 by the ammo- 

 nia. 



Their calculi 

 must he phos- 

 phate of lime. 



Little muriate 

 of soda. 



Much urea. 

 Other sub- 

 stance*. 



Urine of the lion and the royal tiger. 



The urine of the lion, and that of the tiger, are perfectly 

 similar in every respect. They have likewise some analogy 

 to that of man, but they differ from it essentially in some im- 

 portant points. 



First difference.— They are alkaline at the very instant they 

 are voided : on the contrary, those of a healthy man are con- 

 stantly acid. 



It is to the presence of ammonia developed in these urines> 

 that we must ascribe the strong and disagreeable smell they 

 diffuse immediately on issuing from the bladder of these ani- 

 mals. 



Second difference.*— They contain no uric acid, either free or 

 combined with an alkali. At least the analysis of these urines 

 four times repeated afforded me no sensible trace of it. 



The want of uric acid could riot but the more attract my 

 attention, as I had considered its formation to be owing chiefly 

 to animal food. 



Third difference.— The almost total absence of phosphate of 

 lime. 



This might naturally be expected, as this salt is soluble in 

 water only by the help of a superabundance of acid, and the 

 urine in question is alkaline. 



It appears, however, that the kidneys of these animals sepa- 

 rate a certain quantity of this salt from the blood, for I have 

 found slight traces of it in these urines ; while the ammonia 

 is formed only in the bladder, where probably it precipitates the 

 phosphate of lime j and this is no doubt the reason why the 

 urine of these animals is almost always turbid when voided. 



Hence, if calculi be ever found in the bladder of these ani- 

 mals, they can be formed only of phosphate of lime, since they 

 contain no other insoluble substance. 



Fourth difference. — The urine of the lion and of the tiger 

 contains but an infinitely small quantity of muriate of soda, 

 while that of man commonly affords much. 



In these urines we rind a large quantity of urea, much dis- 

 posed to crystallize, and in general but lightly coloured} phos- 

 phates of soda and ammonia ; sulphate of potash ; a mucous 

 matter, and a trace of iron. 



Thes« 



