289 



iio attempts of that kind have been made, since tlie time 

 of Whyte., 



EXPERIMENT VII. 



A fragment of calculus, of the uric acid kind, weighings 

 seventy-nine grains and a quarter, was suspended, for for- 

 ty-eight hours, in a mixture, consisting of four ounces of 

 distilled water, and twenty-five drops of the weak aqua 

 kali puri of the shops, which merely gave it an alkaline 

 taste. It was then placed on a sand heat: temperature 

 varying, occasionally, from 60 to near 100 degrees. After 

 being taken out, and dried, it weighed seventy-four grains 

 and three quarters; so that the loss amounted to four 

 grains and a half. This weak lixivium, it appears, then, 

 operated upon it, acquired a yellow colour, a sweet taste, 

 and precipitated, with a few drops of muriatic acid, a 

 white sediment, easily recognizable, by the small, silky, 

 needle-shaped, crystalline appearance, peculiar to the uric 

 acid. 



EXPERIME>;T VIII'.. 



This same fragment of calculus, after being well washed, 

 and dried, was again immersed, for forty-eight hours, in a 

 lixivium, consisting of only twenty drops of aqua kali puri 

 to four ounces of distilled water, and under the same cir- 

 cumstances. Upon being taken out, and dried, it was 



found 



