[ 130 } 
IV. Experiments and Obfervations tending to Show the Com- 
pofition and Properties of Urinary Concretions. By GEORGE 
Pearson, M.D. F.R.S. Read before the Royal Society, 
December 14, 1797. From the Philofophical Tranfactions. 
[Concluded from the laft Number, page 54. ] 
I SHALL next relate fome experiments, made in order te 
obtain the acid fublimate of Scheele, or lithic acid of the new 
fyftem of chemiftry. 
100 grains of an urinary concretion, which had been pre- 
vioufly fiend to contain principally the above animal oxide, 
were introduced into a tube 5 of an inch wide; which was 
fealed at one end by fufion, and which alfo was fitly bent for 
eolleGting fublimate, and obtaining gaz. The fealed end 
was coated and expofed to fire, firft to a low temperature, 
and gradually to a very elevated onc. 
“x. Gaz was difcharged, which had the fmell of burning 
bone. 
2. Water appeared boiling immediately over the charge, 
which feemed to be burning, and was turned black. 
3. Gaz was difcharged, of the fmell of empyreumatic 
Higuor cornu cervi, and about half a drachm of this liquor 
was in the upper part of the tube. 
A brown fublimate of carbonate of ammoniac appeared 
in the cold part of the tube; but in the hotter part, near’ the 
charge, was tar-like matter, and the gaz difcharged had a 
very offenfive fmell of ig emp animal oil, with which 
was mixed that of aah ac 
The coated ine of the aie was kept red hot, for fome. 
‘time after gaz ceafed to come over. 
The quantity ef gaz amounted to 24 os tela by meafure = 
it confifted of nearly 16 ounces of carbonic acid gaz, and 
the reft was air, with a larger proportion of mirage gaz 
than is contained in atmofpheric air. 
5. There 
