224 Experiments on the Oxygenaied 
secondary object. The salt was chiefly formed 
during the distillation. "The alkali became warm to- 
wards the latter end of the process, especially if the 
absorption of gas was very rapid, a quantity of ca- 
loric being disengaged. In this case, a considerable 
part’of the salt soon crystallized on the lixivium 
being set’ in a cool place, and a great deal of gas 
appeared to escape, which on one occasion I col- 
lected, and found that it precipitated lime from its 
solution in water, and extinguished flame: and, 
therefore, though it had a slight smell of the oxyge- 
nated muriatic acid gas, I believe that it consisted 
chiefly of carbonic acid, as the former occasions no 
precipitation of lime water, which the latter uni- 
formly does. A glass jar, containing 32 ounce- 
measures of this gas, being left over water one 
night, was reduced to about one fourth its bulk. 
The gas that remained seemed to contain more oxy- 
gene than the air of the room; two measures of it, 
with one of nitrous gas, gave 1.53, whilst an equal 
quantity of common air, gave 1.9. 
Before any of the salt appeared to be formed in 
the alkaline solution, I have constantly observed a. 
quantity of earthy matter to be precipitated. This 
_ was carefully separated from the salt, and, after being 
washed repeatedly in boiling water, was suffered to 
dry; but not having examined it with sufficient min- 
uteness to say what it is, I shall content myself at 
