228 NEW SOLVENT FOR STONE IN THE BLADDER. 
Carbonate of lithia dissolves in water at the ordinary tem- 
perature of 60° Fahr., to the amount of one per cent. From 
its sparing solubility it may be said to form the connecting 
link between the earths and alkalis. It possesses a faintly 
alkaline by no means unpleasant taste. No opportunity has 
yet been afforded me of ascertaining whether it passes 
through the circulation unchanged, although analogy would 
lead to the supposition that such was the case. It has a re- 
markable affinity for uric acid; so much so, that if finely 
pulverized lepidolite (a hard siliceous mineral containing; 
three or four per cent, of lithia) be boiled along with uric 
acid in water, urate of lithia is formed. A fact pointed out 
by M. Lipowitz, and which has been lately verified by my- 
self. 
According to the chemist above mentioned, one part of 
carbonate of lithia, dissolved in water, and boiled along with 
an excess of uric acid, dissolves four parts of the latter, 
which are held in solution after cooling. Urate of lithia is 
indeed the most soluble salt which that acid forms. It crys- 
tallizes by evaporation in the shape of small grains, which 
require sixty parts of water, at the temperature of 60° Fahr., 
to dissolve them. It contains 14.4 per cent, of lithia.* 
In order to determine the solvent powers of carbonate of 
lithia, with reference to uric acid and its compounds, at the 
common temperature of the human body, I instituted the 
following experiments: 
A solution of one grain of carbonate of lithia in an ounce 
of distilled water was brought to a temperature of 98°, and 
pure uric acid gradually added in minute portions until it 
ceased to dissolve. The quantity thus taken up was 2.3 
grains. The resulting solution, which remained unchanged 
the following morning, being saturated with hydrochloric 
acid, threw down a precipitate of uric acid, amounting to 
two grains. Now it will be seen, by referring to my paper 
on the "solvents for calculous concretions," published in the 
* Berzelius, Rapport Annuel 1843, page 325. 
