URINARY CALCULI. 569 



of lime, and partly of crystals of ammonia-phosphate of magne- 

 sia. The part of the stone investing this nucleus was composed of, 

 Phosphate of lime, . . 64 

 Ammonia-phosphate of magnesia, 30 

 _______^- Animal matter, . . 6 



100 



Gray-coloured sand from a dog's bladder was analyzed by the 

 same chemist, and found composed of, 



Carbonate of lime . 20 



Phosphate of lime, . . 80 



100* 



In 1825, M. Lassaigne examined a calculus from the bladder 

 of a dog, deposited in the collection of the Veterinary School at 

 Alfort. It was yellowish, semitransparent, and possessed all the 

 characters of cystic oxide mixed with a little phosphate of lime 

 and oxalate of lime. Its constituents by analysis were, 

 Cystic oxide, . . 97*5 



Phosphate and oxalate of lime, . 2*5 



lOOf 



A good many years ago I received from Montreal a small par- 

 cel containing about a dozen of pearls, which had been extract- 

 ed from the bladder of a dog. The colour was rather too dark, 

 and the surface too cloudy to permit these pearls to be used for 

 ornamental purposes ; but they were much more beautiful than 

 the pearls in the Hunterian collection from the bladder of a hog. 



In 1818, Lassaigne had analyzed a calculus from the bladder 

 of a dog. It was yellowish, of an irregular shape, and was about 

 the size of a hazel-nut. It was composed of urate of ammonia 

 mixed with a little phosphate of lime.J 



From these different analyses there is reason to suspect that 

 the calculi of the dog are as much diversified in their chemical 

 constitution as those of man. 



6. The Cat. The only chemist who has examined the calculi 

 from the bladder of the cat is Vauquelin, according to whom 

 their constitution is similar to that of human calculi. 



* Phil. Trans. 1808, p. 235. f Ann. de Cbim. et de Phys. xxiii. p. 328. 

 \ Ann. de Chim. et de Phys. ix. p. 324. Ann. de Chim, Ixxxiii. p. 146. 



