{ 43°] 
XI. Extra& of a firfi Memsir to ferve as a Natural, Chee 
mical, and Medical Hiftory of Human Urine; with fome 
New Faéts on its Analyfis and Spontaneous Alieration. By 
C. Fourcroy aad VauaueE.in * 
is 
F HERE is no animal matter which has been fubjected 
to more examination than urine, and there is none which 
has furnifhed more difcoveries to chemifts. They have, 
however, confined themfelves chicfly to an examination of 
phofphats, which were for a long time called Fufible Salts. 
Margraff, Pott, Schloffer, Haupt, and Roueile the younger, 
were almoft exclufively occupied with them from the time of 
Boerhaave te Scheele. This great attention beftowed on 
phofphats arofe from the intereft infpired by the difcovery 
of the phofphorus of urine, and the ideas which the alche- 
mifts had propagated refpecting the fingular preperties of 
thefe falts. What phyficians have done in regard to human 
urine has fearcely had any relation to its. nature, and has 
fupplied too much to the ridiculous pretenfions of empiri- 
cifm. The difcoveries of Scheele put an end to the inco- 
herence between medical obfervations and the chemical la- 
bours on urine. When the acid, which forms the greater 
part of the urinary caleuli, or the uric avid, was difcov ered, 
as well as the acid phofphat of lime, the formation of thele 
calculi, like thofe of the depots of the precipitates of urine, 
became much eafier to be comprehended than before; and 
it then became poffible to eftablith between the medical ob- 
fervations on urine and its nature, better afcertained, that 
relation which ought conftaatly to have been the phy figian’s 
guide, fince by it rie he could be furnifhed with any exaét 
light. The ufeful inferences which our colleague Berthollet 
has drawn from the examination of urine, and from its na- 
ture, more or lefs acid, in gouty affections, are at prefent 
well known. 
A long feries of enieiteit, undertaken by C. Vauquelin 
and my‘elf, on animal matte:s in general, prefented to us 
* From the Aynales de Chintie, Noe 91. 
G2 Jorg 
