396 A Memoir on the Uric Acid. 
crystals are found adhering to the sides of the 
~ vessel, which may be collected and purified 
by washing them with cold water. The in- 
vention of this process, since described by 
Dr, Egan in the Transactions of the Irish 
Academy, (/) is, indeed, to be attributed to 
Link, who first made it known in his Disser- 
tation, published at Gottingen, in 1788, (m) 
Beside the peculiar variety of calculus which 
consists chiefly of uric acid, Dr. Wollaston, 
in the Philosophical Transactions for 1797, 
described several other well characterized spe-- 
cies ; and proved that the concretions, which 
are found in the joints of gouty persons, con- 
sist of lithic acid united with soda. Dr. 
Pearson, in the following year, was led by a 
long and laborious investigation of the pro- 
perties of the lithic acid, to a conclusion re- 
specting its nature different from that of 
Scheele and Bergman ; for its properties, he 
conceived, agree better with those of an oxide 
than of an acid, and he proposed, therefore, 
to call it the uric ovide.(n) His memoir 
. incited Fourcroy and Vanquelin to repeat and 
extend the experiments of Scheele, whose 
(l) Vol.x. p.-256. 
(m) H. F. Link Commentatio de Analysi Urine et 
Origine Calculi. 
(m) Phil. Trans. 1798; 
