[ io 4 ] 
what was contained in that portion of the fixed alkali, 
which was not neutralized by the acid ; and con- 
fequently the unneutralized earth, in the mixture, 
contained not much more fixed air than what was 
fufficient to faturate it. As the latter of thefe mix- 
tures differed no otherwife from the former, than that 
it contained lefs fixed air ; the fufpenfion of the earth 
in the former muff neceflarily be owing to the 
fixed air. 
In the two foregoing experiments the water con- 
tained, befides the unneutralized earth, and fixed air, 
lome fill fylvii, and a little folution of chalk in the 
marine acid ; which, it may be fuppofed, contri- 
buted to the fufpenfion of the earth : but the follow- 
ing experiment fhews that a calcarious earth may be 
Impended in water, without the addition of any other 
fubffance than fixed air. 
Experiment VII. 
A bottle full of rain water was inverted into a 
yefiel of rain water, and fome fixed air forced up 
into the bottle, at different times, till the water had 
abforbed as much fixed air as it would readily do ; 
1 1 ounces of this water were mixed with 6 _L of 
lime water. The mixture became turbid on "firff: 
mixing, but quickly recovered its tranfparency, on 
fhaking, and has remained fo for upwards for a year. 
This mixture contains 7 grains of calcareous earth; 
and, from a fubfequent experiment, I guefs it to con- 
tain as much fixed air, as there is in 14 grains of 
calcareous earth. 
Experiment VIII. 
Leaft it fhould be fuppofed, that the reafon why 
the earth was not precipitated in the foregoing experi- 
2 ment, 
