WATERS from ICELAND. 101 
ftrongly directed, the mixture was foon melted into a tranfpa- 
rent colourlefs glafs, which afterwards, by being digefted with 
a fmall quantity of diftilled water, was completely diflolved, 
and formed a liquor which had all the qualities of the /iguor /i- 
licum. 
I NEED not take notice here of the quantity of the earth 
and faline matter which were in fome meafure feparated 
from one another in this experiment. I had reafon to fufpedt, 
- that neither of them were obtained in this way without fome 
lofs. The odour emitted by the water in the end of evapora- 
tion, gave reafon to fufpect the lofs of fome part of the falts; 
and it was probable that a part of the earth would remain com- 
bined with the alkali, in a foluble ftate, in the dry extract, and 
would pafs through the filtre, when | diflolved and wafhed away 
the faline matter. 
I THEREFORE planned a fet of experiments, by which the 
quantity of each ingredient in thefe waters might be more cer- 
tainly known ; and began with the following 
Experiments to invefligate the quantity of the un-neutralized alkaline 
falt. 
In making the experiments to decide this queftion, I made 
ufe of an acid, which I had often employed before in experi- 
ments to learn the quantity of pure or cauftic alkali, contained 
in aerated alkalis, and in various barillas, kelps, and other fuch 
heterogeneous mafles. This acid was a quantity of the vitriolic, 
the power of which, in faturating pure alkalis, I had carefully 
examined, and I was accuftomed to add it very gradually to fil- 
‘trated folutions of the above fubftances, until they were exadtly 
faturated ; and then, from the quantity of acid required to pro- 
duce this effect, I learned the quantity of un-neutralized alkali 
which thefe fubftances contained. The fpecific gravity of this 
vitriolic 
