268 . +, Pourercy’s Examination of \ 
and on cooling depofits almoft every thing it contains in 
fmall cryftals. 
WII. Seventy-two parts (grains) of this calculus, diftilled: 
in’a {mall glafs retort over an open fire urged fo.as to bring’ 
the veffe! to a red heat, produced water of ammonia like 
hartfhorn, and a brown’ fublimate without oil: there re-’ 
mained, twelve, parts or 4 of a black charry fubflance, 
which preferved its colour on red hoi iron in the open air. 
The brown fublimate, weighmg 28, parts, grew white by a, 
fecond fubhmation ; it was deftitute of fmell, even when, 
moiftened by an alkali; its. tafte, was acid ;, it. diffolved in 
water by ebuilition; alcohol diffolved it alfo, but in lefs 
quantity than water; it did not precipitate lime, water, and 
refembled the fuccinie acid, ’ 
From the facts in thefe feven feGtions, Scheele concludes 
that the urinary calculus does not contain either fulphurie 
acid or lime; \but that it is compofed of a conerete ,acid, 
oily, volatile, mixed with a little gclatinous matter, which . 
acquires new properties and changes its nature by tee nitric 
acid. 
‘ VII. He fays he ete a little, of this saa in all UIs 
even in that of children. This liquor evaporated to =i, of 
its weight (14 pounds reduced, to.2, ounces) depofits a fubtle 
powder fimilar to the calculus, which adheres to the veffel, 
and which the cauftic alkali diffolves very eafily.. The de-, 
pot from the urine) of patients labouring under fevers ex- 
hibited the-iame nature ;, it is formed in clofe veilels as well 
as in thofe that are open;_it is re-diffolved by means of 
*heat, and its. precipitation is, owing only.to the cooling of 
the urine. ; 
TX. All urines thus contain phofphat of lime, kept in 
folution by an exeefs of the phofpheric acid; which is the 
reafon thet it reddens blue paper, and. depofits a w hite 
powder: Ly means-of ammonia. Urine gives of it 35 of its 
weight, This precipitate diffolved in the nitric acid is 
sendered 
