LEUOOMAINS OF THE UBINE. 469 



the toxicity of urine were made early in the century by Vauquelin 

 and others. On the other hand, disbelievers in the toxicity of urine 

 were not wanting. Thus Frerichs maintained that death, resulting 

 from intravenous injections of urine, was due to the suspended solid 

 elements of the urine ; that urea itself was harmless, but that it could 

 by the action of a ferment give rise to the poisonous ammonium car- 

 bonate. Voit was among the first to point out that potassium salts, 

 on account of their toxicity, could play au important part in uraemia. 

 It can now be positively stated that normal urine does possess a cer- 

 tain degree of toxicity. It is more difficult to decide upon the nature 

 of this poison. Feltz and Ritter (1881), and independently Asta- 

 schewsky, arrived at the opinion that the toxicity was chiefly due to 

 the potassium salts of the urine. Schiffer, while acknowledging the 

 presence and action of the inorganic salts, maintained that the urine 

 contained a definite organic poison, for the reason that the concen- 

 trated aqueous solutions from alcoholic extracts of the urine residue, 

 deprived of inorganic salts, killed large rabbits in doses correspond- 

 ing to 1— 1|^ liters of urine. 



According to Bouchard, 30-60 c.c. of normal urine, injected in- 

 travenously, will kill a rabbit weighing one kilogram. Hence a 

 man weighing 60 kilograms, and excreting per day 1200 c.c, would, 

 if 50 c.c. are necessary to kill one kilogram of living matter, secrete 

 enough poison to kill twenty-four kilograms of animal. Inasmuch 

 as the amount necessary to kill one kilogram of animal is designated 

 as one urotoxy, therefore, in the above case twenty-four urotoxies 

 are formed per day. The urotoxic coefficient is the number of uro- 

 toxies which one kilogram of man forms in twenty-four hours. 

 Therefore, |^ = 0.4, the urotoxic coefficient. The average normal 

 urotoxic coefficient is placed by Bouchard at 0.464. It follows, 

 therefore, that an average man would, if the excretion of urine was 

 stopped, be killed in fifty-two hours. The variations of the urotoxic 

 coefficient in the normal individual is limited. In disease it rarely 

 exceeds 2, and rarely falls below 0.10. 



According to Bouchard, five kinds of poisons may be met with in 

 the urine, producing narcosis, salivation, mydriasis, paralysis, and 

 convulsions. The day urine, which is chiefly narcotic, is 2-4 times 

 more toxic than the sleep urine, which induces convulsions and is 

 antagonistic to the former. The toxicity is independent of the den- 

 sity, since night urine is more dense than that secreted during the day. 



The greater part of the toxicity of urine is ascribed by Bouchard to 

 organic poisons, especially coloring-matters, whereas potassium salts 

 are regarded as the cause of but a small fraction of the toxicity. 



L6pine likewise found that about 60 c.c. of urine sufficed to kill 

 one kg. of animal. The inorganic salts, however, were ascribed by 

 him a much greater importance, inasmuch as he estimated that 85 

 per cent, of the intoxication was due to this cause. The remainder 



