[.299 }- 
The reft of the figures are only 
intended for thofe who fhould like 
to engage farther in this entertain- 
ing branch of natural philofophy, 
| aut to produce thofe kinds of air. 
which are liable to be altered or 
abforbed by water. 
Fig, X, A wooden trough to be 
filled with mercury, for fuch ex- 
periments . with air as cannot be - 
done in water. Man; kinds of airs | 
are saaned themfeHres by water, 
as is fixed air, and all thofe aerial 
fluids which fhould rather be claffed 
among vapours, as alkaline air, 
acid air, &c. of which an account 
. may be feen in the works of Dr, 
_ Prieftley, and which will foon be 
_ tréated in a more ample manner 
by Abbe Fontana. 
