1813.] discharged in Diaieles MeUltus, S5 



3. Of the remaining Ingredients of Diabetic Uriiie, 



With regard to the action of chemical tests on diabetic urine^ 

 nnd to the nature and proportion of the saline snhstances which it 

 contains, I have nothing to add to the accurate reports which 

 have already been given by Nicholas and Gueudeviiie, and by 

 Dr. Bostock. With their experiments my own, for t'^? most 

 part, coincide; and tend to estabhsir the conclusion, that xhd 

 different salts exist in diabetic urine almost in the" same propor- 

 tion to each other as in the healthy state, but that they fall con- 

 siderably short of the same absolute quantity. 



The nature and amount of the pmnary a?iimal fluids (as they 

 have been termed by Dr. Bostoik) which are contained in 

 diabetic urine, can scarcely, I apprehend, be determined, till 

 we are in possession of tests which, while they as precipitants 

 of those fluids, shall have no agency on snliue cstances. In 

 the present state of this branch of animal chemisi /=, it unfortu- 

 nately happens, that all the tests with which we are a<.qnainted 

 afford nothing more than equivocal appearances when applied to 

 the urine. Acetate of lead, for example, is not only pr cipirated 

 by animal mucus, but by the muriatic and phosphoric salts which 

 abound in that fluid. 



It has been disputed whether the saccharijie matter exist!. ;^ in 

 diabetic urine be identical or not with vegetable sugar. Accord- 

 ing to Cruikshank,* both substances, if due allowance be made 

 for the saline ingredients of diabetic extract, yield, by the action 

 of nitric acid, very nearly the same proportion of crystals of 

 oxalic acid. Nicholas, and Gueudeviiie, and Thenard, have 

 obtained, also, by the fermentation of diabetic extract, very 

 nearly the same weight of alcohol, as would result from an 

 equal weight of vegetable sugar, f These circumstances appear 

 to me to be decisive, with respect to the close similarity between 

 the two substances. On the other hand, it has been asserted, 

 that the saccharine matter of diabetic urine cannot, like vegetable 

 sugar, be brought to assume a crystallized form. The absence 

 of this property, however, is not invariable ; for I have had an. 

 opportunity of observing distinct crystals of sugar, in a portion 

 of diabetic syrup long exposed to the atmosphere. A mouldy 

 scum formed on its surface, which was repeatedly remov^ed and 

 reproduced. In this way much of the animalized matter was 



to diet, I did not find, however, that the smallesi impression was made either 

 upon the state of the symptomii, the quantity of uriue, or its chemical composi- 

 tion ; and I, therefore, discontinued the practice. From a solitary case of so 

 hopeless a disease as diabetes it would be unfair to deduce a condemnation of 

 this or any other plan of treatment. 



* Roilo on Diabetes, edit, p. 429. f Ann, de Chira.. xfiv. andlix-. 



e 2 



