WATERS from ICELAND. 109 
To remove this fcruple, I took gr. 10,000 of diftilled water, 
and added gr. 112 of the diluted acid. This mixture was ther 
boiled down, in the fame manner as the Iceland water ; that is 
to fay, in a glafs which had an oval or nearly globular body, 
about 5 inches deep, with a neck as long, and half an inch 
wide. This glafs was placed in a {hallow fand-heat, the bottom 
of which was a flat iron plate. The boiling was continued 
until three fourths of the water were evaporated, and then, re- 
moving it from the fire, I added gr. 40 of the dilute folution 
of falt of tartar. This neutralized it exactly, and fhewed that 
no part of the acid had been diffipated in boiling ; and it con- 
tinued to fhew the figns of fufficiently exact faturation, after I 
had evaporated it further to the weight of one ounce, in which 
ftate, any fuperfluous alkali, by being lefs diluted, would have 
been more eafily difcernible. 
Experiments to determine the nature and quantity of the earthy: 
matter. 
Havince thus determined the quantity of unfaturated alkali 
in thefe Iceland waters, my attention was next turned to the 
earthy matter. A fmall part of this earthy matter came into 
view in the boiled and neutralized portions of thefe waters with 
which I had made the above defcribed experiments. The neu- 
tralized liquors were a little muddy, and depofited flowly a 
fmall quantity of fediment, which colle¢ted itfelf clofely to the 
bottom of the glafs, and adhered to it flightly. This fediment, 
in the Rykum water, was deeply tinged with the colouring mat- 
ter of the litmus ; in the Geyzer water, it had a brown tinge, 
and there was a little more of it than in the other. I collected 
thefe fediments, by firft- decanting the greater part of the li- 
quor from them, and afterwards filtrating the reft in a {mall 
filtre, in which the fediment was wafhed, by paffing diftilled 
water 
