88 Mr. T. Taylor on some 



red-hot. It was redissolved in water, and mixed with alcohol 

 and chloride of platina. Chloride of platinum and potassium 

 was thrown down, which when washed with alcohol and care- 

 fully dried weighed 10*32 grs., = 1-99 PO. 



The quantity of ammonia was estimated by boiling the pow- 

 dered calculus in a solution of potass, transmitting the am- 

 monia evolved through diluted muriatic acid, and precipita- 

 ting it in the ordinary manner by chloride of platina. 11*40 

 grs. yielded 4*57 of chloride of platina and ammonia, = 3*10 

 per cent. I do not, however, place much confidence in this 

 mode of estimating the ammonia. The result of the analysis 

 of this calculus, calculated in 100 parts, is therefore as follows : 

 it is compared with an analysis of the calculus which had no 

 history, in which the quantity of potass is rather greater: — 



Uric acid mixed with a trace of oxalate of lime 78*64 78*36 



Potass 10*42 13*19 



Ammonia 3*10 3*09 



Lime 1*89 1*49 



Magnesia 0*00 0*29 



Phosphate of lime 0*32 0*02 



Animal matter 2*73 0*43 



Water 1*67 1*80 



Sulphate of soda with chloride of sodium . . traces 



98*77 98*67 

 By another analysis, in which the quantity of potass was 

 alone estimated by calcining the calculus until nothing but 

 carbonate of potass was left, and precipitating the dissolved 

 salt by chloride of platina, 10*72 per cent, of potass was found 

 in the first, and 13*07 in the second calculus. 



The potass in these concretions is probably derived from 

 the leaves and other vegetable matter on wruch the Iguana 

 partly subsists, while the carnivorous or insectivorous habits 

 of the reptile are indicated by the large quantity of uric acid 

 they contain. 



Urinary Calculus from the Sturgeon, consisting of Diphosphate 

 of Lime. Beluga stones. 



These calculi are found by the fishermen of the Caspian 

 Sea and of the Volga in a species of Sturgeon (Acipenser 

 Huso, Linn.). The statements of different authors as to the 

 situation of the stone in the fish, are very conflicting, some 

 describing it as occurring in the air-bladder, others in the 

 head and stomach. In Schrober's Memorabilia Russico- Asi- 

 atica, as quoted by Klaproth, it is said to be most frequently 

 found in a small pouch communicating with the pancreatic 



