r 114 ] 



XX. An experimental Inquiry into the Nature of Gravelhj 

 and Calculous Concretions in the Hwnan Subject', and the 

 Effects of Alkalive and Acid Substances on them, in and 

 out of the Body. By Thomas Egan, M.D. M.R.I.A. 



[Concluded from p. 36.] 



Experiment XI. 



xxs children are such frequent sufferers, Mr. Richards sug- 

 gested the propriety of ascertaining whether the alkaline in- 

 fluence might be weakened by the addition of sugar. One- 

 half of a calculus, of the uric acid kind, weighing 185^ 

 grains, extracted by my friend Mr. Richard Dease, and 

 (though under the most unpromising circumstances) with a 

 dexterity and success not to be exceeded by his late father, 

 was suspended in a lixivium consisting of eight ounces of 

 distilled water and twenty drops of weak aqua kali puri 

 (partly aerated), and scarce imparting an alkaline taste. 

 To this were added thirty-six grains of sugar, which were 

 found adequate to sweeten it sufficiently. After remaining 

 forty- eight hours in a temperature varying from bb to near 

 100 degrees, or a medium one of 74 degrees, being dried and 

 weighed, it was found to lose ten grains three quarters. The 

 addition, then, of saccharine matter cannot diminish, but 

 may add to the alkaline energy. 



Experiment XII. 



Ten grains of very pure crystallized carbonate of potash 

 were dissolved in four ounces of distilled water. In this 

 filtered lixivium was suspended a fragment of calculus, of 

 the uric acid kind, vieighing seventy-two grains and a quar- 

 ter, for forty-eight hours, on a sand-heat, varying from 50 

 to 100 degrees (for the fire was not kept up during the 

 night). Being taken out, dried, and weighed, it was found 

 to have lost seven grains and a quarter. The solution had 

 a yellowish green colour, different from the light yellow 

 tinge of the pure alkaline ones. It also lost its taste, but 

 w^ithout becoming sweet. A quantity of flocculent animal 

 matter was separated, and the dissolved uric acid was, for 



the 



