Experiments on Urine. 24% 
“Tt mutt be obferved, that the urine employed in thefe 
trials fhould be recent, and not kept for any length of time, 
as it is well known that ammania is foon produced, w Kieth 
would render the refults extremely uncertain. It was 
thought proper to give the quantity of precipitate thrown 
down by the principal re-agents, when added to healthy 
urine; for by this means we {hall be better enabled to de- 
teé&t any remarkable deviation from the healthy ftandard. 
The quantity of four ounces was conceived to be the mof 
convenient, as in many ¢afes we might not be able to pro- 
cure more, and a lefs quantity could only afford uncertain 
-refults. 
Upon the whole, therefore, we would obferve, that the 
proportion of extractive matter may, in fome meafure, be 
determined by an infufion of oak bark, or rather galls; the 
quantity of phofphoric falts by the muriat of barytes, or 
acetite of lead ; that of the muriatic falts by the latter fub- 
ftance ; the proportion of phofphat of lime by pure ammo- 
nia, or any of the alkalies, and the lithic acid by the pro- 
cefs already deferibed. (See A.) 
In morbid ftates of the urine, the coaguiable part of the fe- 
rum is deteted by the nitrous acid, and even by heat ; bile 
_ by the nitrous or muniatic acids; and the condition of urine 
accompanying rheumatifm and other inflammatory com- 
plaints by the corrofive muriat of mercury, and fometimes 
by alum. With eae to fugar rae is met with in dia- 
already fully Geen : we would oa Madhu propofe, 
W hen 
* In confirmed diabetes the urine is {weet to the tafte. In one cafe ** Mr, 
Cruickthank took 36 oz. troy weight of urine, and it yielded by evapora 
tion 3 oz. x dr. of faccharine extract, of the appearance of molafies, bur 
thicker, having nearly the confiftence of wax, and fomewhat tenacious, 
If the whole of the day’s urine had been evaporated, it would (at the fame 
rate) have yiclded about 29 oz. an aftonifhing quantity to be formed and 
feparated daily from the fyftem. By ftanding in the air it became oe 
R 3 ’ aud 
