45 7 
/ 
ii6 Mr. Hatchett’s Analysis of the earthy Substance 
in solution. The remainder was then evaporated, without leav- 
ing any residuum. 
» 
EXPERIMENT 2. 
About 200 grains of the earth, rubbed to a fine powder, were 
put into a glass retort, into which I poured three ounces of 
concentrated pure muriatic acid. The retort was placed in sand, 
and the acid was distilled, till the matter in the retort remained 
dry. Two ounces of muriatic acid were again poured on it, and 
distilled as before, till only one fourth remained. The whole 
was then put into a matrass, which was placed in an inclined 
position, so that when the earth had subsided, the liquor might 
be decanted, without disturbing the sediment. 
When it had remained thus for 1 2 hours, the acid was care- 
fully poured into a glass vessel ; but, as 1 observed that it was 
not so perfectly transparent as before it had been thus employed, 
I suffered it to remain 24 hours, but did not perceive any sedi- 
ment. Half of this liquor was diluted with about twelve parts 
of distilled water, and, after a few hours, a very small quantity 
of a white earth subsided. 
This however did not appear to me to be a precipitate caused 
by a change in the chemical affinities, but rather an earthy 
matter which had been suspended in the concentrated acid, 
and afterwards deposited, when the liquor was rendered less 
dense by the addition of water. To ascertain this, I poured the 
remaining portion of the concentrated liquor on a filter of four 
folds : it passed perfectly transparent, and, although diluted with 
twenty-four parts of water, it remained unchanged, and as pel- 
lucid as before. I now filtrated the former portion, and added 
it to that already mentioned. 
