1864.] 



of Diabetes artificially by Cold, 



539 



marked in this urine than in that made before the application of cold. 

 The total quantity of urine obtained after death was between two and three 

 drachms. 



Experiment 2. — This lasted seven hours and a half, in consequence of 

 an interruption caused by the melting of nearly all the ice surrounding the 

 rabbit. The temperature fell from 101° F. in the mouth to 69° F. after 

 death. The urine made before the application of cold contained no sugar. 

 The quantity of urine obtained after death was so small that I was unable 

 to prove to my own satisfaction that sugar was present in it. 



Experiment 3. — This lasted four hours and five minutes. The tempe- 

 rature at the commencement was 101° F. in the mouth. The urine made 

 before the icing was alkaline from fixed alkali. It did not give any trace 

 of sugar, and when mixed with yeast and put in a warm place it rapidly 

 putrefied. Its specific gravity was 1014. The urine obtained after death 

 was strongly acid, and contained crystals of oxalate of lime. It gave a plen- 

 tiful reduction of oxide of copper when boiled with sulphate of copper and 

 liquor potassse. When boiled with liquor potassee alone, it deepened 

 markedly in colour. When mixed with yeast it quickly fermented most 

 distinctly. The specific gravity was 1020. 



I sent my results to Professor Briicke, and I asked him to repeat my ex- 

 periments, and I have received from him the following account written in 

 June 1864. 



"The urine of rabbits always shows small quantities of sugar. No regi- 

 men could make it disappear entirely. Hay, grass, carrots ; hay and grass 

 mixed, and absolute fasting were tried, but all showed traces of sugar in 

 the urine. 



" The quantity of urine obtained was too little to allow of the fermentation 

 test being successful, but by using the lead process, the potash, the bismuth, 

 and the copper test gave very feeble evidence of sugar. The experiments 

 agreed so well, that I can have no doubt that sugar is always present. 

 The rabbit proved to be pregnant, and as I had found that in the last stage of 

 pregnancy sugar is often increased in the urine, I thought this might ac- 

 count for the sugar in the urine ; so I took a strong male rabbit, and then 

 again I found that traces of sugar occur normally in the urine of rabbits as 

 in the urine of man. 



Then I repeated your experiment. Notwithstanding what I had found, 

 the results were striking. The quantity of sugar in the urine after freez- 

 ing was incomparably greater (war ganz unvergleichlich gross). 



" The urine after freezing differed also from the urine of health in the fact 

 that, after precipitating with acetate of lead and filtering, the clear fluid 

 gave a very small precipitate with basic acetate of lead ; but on the addition 

 of ammonia, a plentiful white precipitate fell and deposited itself, leaving 

 the fluid clear. 



" I have not made any quantitative experiments; they are not much to be 



