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PROPERTIES OF URIC ACID.

URIC ACID.

PART CIX.

This acid exists in the urinary calculi, and also in humanurine. That species of calculus which resembles wood in its colourand appearance, consists almost entirely of uric acid. It wasformerly called lithic acid, a name now superseded by the judi-cious remarks of Dr. Pearson, to whom we are indebted for athorough knowledge of it.

PROPERTIES OF URIC ACID.

Uric acid crystallizes in thin plates. It has very little tasteor odour. It is insoluble in cold, but soluble in 300 parts ofboiling water, it then reddens delicate vegetable blues. It is notacted upon by muriatic acid. Sulphuric acid, assisted by heat,decomposes it. It is soluble in nitric acid, and communicatesto it a pink colour. The solution tinges animal matter of thesame colour. It combines readily with alcalies and earths, andforms salts, which are decomposable by most of the other acids.The combination of uric acid with potash or soda, forms com-pounds nearly void of taste. The last is found crystallized in thehuman body, forming the gouty concretions of those afflictedwith the gout.

The acids called Formic and Zoonic are nothing more thanacetic acid.