Experiments on Urine, 249 ° 
times with the nitrous acid : when the difeafe takes a favour- 
able turn, this effect will im a great meafure ceafe, and the 
lateritious fediment make its appearance. 
é 
In fevers, particularly fuch as are accompanied with a 
ftrong action of yeffels, fimilar phenomena may be obferv- 
ed; but in this cafe the lateritious fediment, which never 
fails to make its appearance at the crifis or abatement of the 
difeafe, is much more remarkable and conftant; and the 
nitrous acid, when added to the urine before the Gapolinom 
takes place, gives it a pretty deep red tinge. » 
In gout, too, the termination of the paroxyfms is moft 
perfe€tly indicated by a copious lateritious fediment; and 
when this fuddenly difappears, and the urine at the fame 
time affords a precipitate with the murjat of mercury, 
freth attache r relapfe may be expected. We have gene+ 
rally found is fediment to be compofed of lithic Cai 
_ phofphat of lime, and fome peculiar animal matter but 
little foluble in water: it has by fome been fuppofed to 
confift entirely of lithic acid; but this fot the moft part 
conftitutes the fmalleft part, 
In jaundice, a very {mall quantity of bile may be dete&ted 
in the urine by the nitrous or muriatic acids, but more par~ 
ticularly the latter. .When, therefore, the urine ceafes to 
become green on the addition of thefe acids, we may infer 
that the obftruétion to its paflage into the duodenum is re- 
moved, and that, confequently, the yellownets of the - fkin, 
&c. will foon difappear. 
The fpafmodi¢ affections that take place in many nervous 
complaints are immediately indicated by.the rine, which 
upon the approach of thefe will moft generally be found 
tranfparent, large in quantity, and abounding in faline, but 
containing bats any extractive, matter, Similar. appear- 
ances have been obferved to precede delirium in fevers. This 
ftate may be difcovered by infufion of oak bark, with which 
it will hardly give any precipitate, and by the-acetite of lead, 
which will produce a very copious one, 
Tn 
