WATERS from ICELAND. 97 
voyage, this matter being one of thofe volatile ingredients of 
mineral waters, which are the moft liable to be evaporated or 
changed by the action of the air and other caufes. I therefore 
think it fufficient to mention, that thefe waters contained a {mall 
quantity of this fubftance. 
I BEGAN by making a few preliminary trials, to acquire fome 
notion of the nature of thefe waters. f 
1. Aw equal quantity of lime-water being added to the Ice- 
land waters, there was a little diminution of tranfparency, but 
only in the fmalleft degree, and no fediment was formed. 
2. Mitp volatile alkali produced no effect whatever. 
3. Paper ftained blue with the March violet, being dipped 
into the water and dried, had its colour changed a little towards 
a green. 
4. Campric ftained to a bluifh purple, with infufion of 
litmus, aflumed a more perfect blue colour, when dipped into 
the water and dried. 
5-. AciD of fugar did not produce a perceptible muddinefs or 
precipitation. 
6. Nor did the folution gf corrofive fublimate. 
4. Tue folution of fal faturni (plumbum acetatum) made 
the water very muddy and white, but a fmall quantity of 
diftilled vinegar rediffolved nearly the whole of the precipitate, 
and made the water almoft perfectly clear again. 
8. Tue folution of barytes in muriatic acid made the water 
become muddy, and depofite a fediment, which was not redif- 
folved by adding purified nitrical acid. 
9. Tue folution of filver produced a ftrong muddinefs and 
confiderable precipitation, which was not rediffolved by adding 
purified nitrical acid. 
Tue laft trial fhewed the prefence of the muriatic acid, and 
the one preceding it, that of the vitriolic acid in the compofition 
of thefe waters; but by the 3d, 4th and 7th, I alfo learned, 
that there was more than enough of alkaline matter to faturate 
Vor. III. N both 
