, of Atmospherical Air, Sc. 155 
the above 121.95 grains contain of pure barytes 
; 81.70 grains, 
which when the above...-...----+-+.s:02---+ 18. 44 grains 
of carbonic acid are added, reproduce 100.14 grains 
of aérated barytes. I should observe, that I added 
one grain to the weight of the ponderous spar, as an 
allowance for some loss, which I had reason to think 
took place ; but I really believe I over-rated it. 
EXPERIMENT II. 
One hundred grains of chalk (which had been 
kept for upwards of half an hour in a strong red 
heat, in order to expel any moisture it might con- 
tain) were dissolved in diluted muriatic acid: 40 
grains of carbonic acid gas were disengaged, so 
that the pure lime amounted to 60 grains. Having 
precipitated the lime by means of the oxalic acid, 
and carefully filtered, washed, and dried the pro- 
duct, it weighed 1333 grains. The oxalate of lime 
consists, according to’ Bergman,* of 48 parts acid, 
6 parts of water, and 46 parts of pure lime. The 
above 1333 grains, therefore, contained 61.52 grains 
of pure lime, which corresponds very nearly with 
the chalk employed when the carbonic acid is de- 
ducted from it. 
Not being able to account for the excess of 1.52 
grains, it occurred to me that it might be owing to 
insufficient drying of the oxalate: which I found was 
actually the case. But I choose to give the result as 
* Dissertation on the Acid of Sugar. 
