tai 



vriiary system is to be considered as the emunctory of the whole econo- 

 my, one would expect to find in it, in certain proportions and under dif- 

 ferent circumstances, the whole of the constituent principles which ana- 

 lysis has hitherto discovered in our solids and liquids. Hence, douhtless, 

 the difference in the results obtained by the chemists who have investi- 

 gated the nature of the urine, by allowing it to run into decomposition, or 

 by applying to it various re-agents. 



As the urine is, of all our fluids, that which has the greatest tendency 

 to putrefaction, it should be examined shortly after being voided; it is 

 then distinctly acid, but in a very short time, and especially if the heat of 

 the atmosphere promotes and accelerates these changes, it becomes tur- 

 bid, its component parts separate and form various precipitates. Urea 

 and gelatine, which alone of its constituent principles are capable offer- 

 mentation and decomposition, give out ammonia, acetous and carbonic 

 acids, and from the chemical attraction between these newly formed sub- 

 stances, and from the primitive elements, there are produced new com- 

 pounds, the knowledge of which is of the department of chemistry. 



Of all the constituent parts of urine, the most essential is a substance 

 of the consistence of syrup, deliquescent, susceptible of crystallization, 

 to which M. Fourcroy has given the name of urea. This substance to 

 which the urine owes its characteristic properties, its peculiar colour, 

 smell, and flavour, which was imperfectly known to several chemists who 

 had sketched some of its features, giving it different names, according to 

 the notions they entertained of its nature, was never well understood till 

 the late investigations of this celebrated professor*. It is a compound 

 in which azote prevails, as is shown by the immense quantity of carbo- 

 nate of ammonia, which it gives out in distillation; it may be considered 

 as the most animalized product, having such a tendency to the putrid 

 fermentation, that, even while in the animal economy, it is liable to 

 that decomposition, and might overcome the antiseptic influence of the 

 vital power, if nature did not get rid of it by the evacuation of the urine. 



Sufficient attention has not hitherto been paid to the symptoms of uri- 

 nary fever, an affection occasioned by the protracted retention of the 

 urine within the bladder. I have observed, on several occasions, that 

 no kind of fever is attended with more marked signs of what physicians 

 term putridity. The urinous and ammoniacal smell exhaled from the 

 body of the patients, the yellowish and oily moisture of their skin, the 

 parching thirst with which they are tormented, the dryness and redness 

 of their tongue and throat, their frequent and irritable pulse, combined 

 with a flaccid and doughy feel of the cellular tissue, every thing indicates 

 that the animal frame is threatened with the most speedy and dangerous 

 decomposition. 



I observed similar appearances in a cat and in a rabbit, in which I 

 tied the ureters. Nothing is easier than to find the ureters, and to per- 

 form this experiment. After a crucial incision of the parit tes of the 

 abdomen, on the left side, the intestines are pushed aside to the left, so 

 -as to apply a ligature on the right ureter, they are then pushed to the 

 right, while the left ureter is tied. Both ureters are seen through the 

 peritoneum, situated behind that membrane, in the lumber region. When 

 the ligatures have been applied to the ureters about their middle, the di- 



* See his work entillcd. System* des Connoissances CJu^ques. 8vo. torn, X. page 

 753. 



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