297 



•^ith the urine: as the small quantity, that can be con- 

 veyed there, must, in the first place, neutralize the un- 

 combined phosphoric acid, in all urine; the benzoic, in 

 children's; and decompose the ammoniacal and magnesian 

 phosphats, in that of every period of life. It must be 

 acknowledged, its efficacy is partly counteracted by these 

 circumstances, which should never be overlooked, and al- 

 ways taken into account, in practical application. RefeiTing 

 to Fourcroy's instructive essay on this subject, Memoii'es of 

 the National Institute, and Connoissances Chimiques, let 

 us here once luore appeal to the test of experiment. 



EXPERIMENT XVII. 



A fragment of calculus, weighing eighteen grains one 

 quarter, of the uric acid kind, was suspended, for forty- 

 eight hours, in an alkaline lixivium, consisting of four 

 ounces and a half of recent urine, and twenty drops of 

 a very weak, and partly aerated, caustic lixivium: medium 

 temperature about 74 degrees. On being taken out, and 

 dried, it was found to have lost one grain three quarters: 

 a considerable quantity, from so small a specimen. To 

 the filtered solution, were added a few drops of dilute 

 marine acid; which, after a few minutes, precipitated a 

 reddish crystalline matter, in a triple proportion of what 

 generally occurs in the natural state of urine. 



From the above experiments, therefore, it appears no 

 longer doubtful: First; that pure lime, even in the small 



proportion 



