106 



nouf is due of having been the first to discover 

 the different constituent parts of these concre- 

 tions; however, as the French Chemists had 

 near 600 different stones to analyse, and before 

 the work was published, had an opportunity 

 of comparing- it with WOL,:LASTON T S, it does 

 contain very important additions, and presents 

 us with a number of different modifications of 

 these substances in the composition of stones. 

 Besides the constituents, which WOIXASTON 

 had discovered, they found two others, viz* urate 

 of ammonia, and silica, the latter of which wa^s 

 only found in two instances; and the former, 

 BRANDE has lately endeavoured to prove to be 

 nothing else than uric acid united to urea ; but I 

 cannot consider his reasons for this opinion as 

 completely satisfactory. FOURCROY and VAIN 

 QUELIN tried, whether it might not be possible 

 to remove the stone without an operation, by in- 

 jecting into the bladder either very dilute acids 

 or alkalies, accordingly as the stone consisted of 

 uric acid or earthy salts ; but I do not know that 

 this experiment has been attended with any suc- 

 cess. They also tried to discover the circum- 

 stances, which gave rise to the generation of cal- 

 culi from urine; this, however, still remains a 

 secret, and we know no more about it, than what 



