[ I0 3 ] 
tranfparent. The mixture was kept three or four days 
flopped up, during which time it remained perfe&ly 
clear, without depofiting any more fediment. The clear 
liquor was then poured off from the fediment, and 
boiled for a few minutes, in a Florence flafk ; it grew 
turbid before it began to boil, and difcharged a good 
deal of air ; fome earth was precipitated during boil- 
ing, which being dried weighed 13 grains. 
This fhews that there was really, at lead 13 grains 
of earth fufpended in this mixture, without being 
neutralized by any acid ; the fufpenfion of which 
could be owing only to its being united to more than 
its natural proportion of fixed air. But, as a further 
proof of this, I made the following experiment. 
Experiment VI. 
I took the fame quantities of rain water, folution 
of chalk, fpirit of fait, and fixed alkali, as in the 
laft experiment, but mixed them in a different order. 
The fixed alkali was firft dropped into the fpirit of 
fait, and when the effervefcence was over, was di- 
luted with 4. the rain water. The folution of chalk 
was then diluted with the remainder of the rain water, 
the whole mixed together, and the bottle immedi- 
ately flopped, and lhook vehemently. . A precipi- 
tate was immediately formed on mixing, which 
could not be re-diffolved on fhaking. 
It muff be obferved, that, in the firfl of the two 
foregoing experiments, all the fixed air contained, in 
the alkali was retained in the mixture, none being 
loft by effervefcence ; whereas, in the laft experi- 
ment, the greateft part of the fixed air was diflipated 
in the effervefcence) no more being retained than 
what 
