Scientijic Intelligence. 191 



Uric acid, - - - - - - 7 



Uric acid, covered with one or more fusible coats, - 9 



Urate of ammonia, - - - - - 1 



Fusible calculi, without a distinct nucleus, - - 7 



Phosphate, with a considerable proportion, (0.13) of carbonate 



of lime, - - - - - - 1 



81 



One remarkable fact is the variety in Wirtemberg of calculi form- 

 ed of uric acid, if the number of them be compared with that which 

 is generally found in England. M. Rapp has found seven out of 81 

 in his collection ; while in tlie collection of Guy's Hospital in Lon- 

 don, 22 are met with among 87 ; at Norwich, 66 out of 181 (Mar- 

 cet) ; at Manchester, 71 out of 187, (Henry,) without counting 39 

 others, composed of uric acid and of phosphate ; of 150 calculi, in 

 Hunter's Museum, and in the collection of Sir E. Home, there are 

 61 formed of Uric acid, including 45 containing a small proportion of 

 phosphate (Brande.) In the collection of Bristol, Smith found 73 

 calculi of uric acid, out of 218, the total number. 



Calculi of uric acid are not, therefore, common in Wirtemburg ; 

 this substance, however, is the most generally diffused throughout 

 them. M. Rapp counted fifty seven of which only the nucleus was 

 formed of it. This nucleus is frequently very small, sometimes only 

 a line in diameter ; in many of these concretions the oxalate of lime 

 is mixed with uric acid ; sometimes, but rarely, coats of uric acid 

 alternate with coats of phosphate. 



M. Rapp found no stone composed entirely of phosphate of lime, 

 but frequendy this salt was mixed with ammoniaco-magnesian phos- 

 phate. The phosphated earths form but rarely the first nucleus of a 

 stone ; most frequently they form the external coats when the nu- 

 cleus is already formed. This is frequently observed in mulberry 

 calculi ; occasionally, a certain quantity of carbonate of lime is mix- 

 ed with the phosphates. These calculi may be formed without any 

 particular diathesis, and in a man in good health, whenever any ex- 

 traneous body get into the bladder, they- become the most volumin- 

 ous calculi. Earle described one (Phil. Trans. 1807,) that weighed 

 four ounces. An animal regimen appears singularly favorable to the 

 deposition of phosphated earths in the urine. 



The presence of urate of ammonia in urinary calculi has been con- 

 tested by M. M. Brande, Henry, and Marcet ; and the signs which 

 Prout has indicated, to recognise this salt, are all doubtful. M. 



