{ 99 ] 
proach néar to the goodnefs of 
common air. This gave me fome 
fufpicion, that this inflammable air 
might be fufceptible of a ftill more 
remarkable correction or purifica- 
tion, at leaft in appearance, with- 
out lofing its explofive quality. 
On purpofe to difcover the whole, 
¥ left forme inflammable air upon 
perficaria, and fome upon wallnut 
leaves, during forty-eight hours, 
Keeping the jars continually in the 
Open air. 
I tried firft the air oF the fa in 
which the wallnut leaves were, in 
the manner familiar to Dr. Prieftley 
and in that of A. Fontana; and re- 
peated each trial twice with the fame 
refult. I found the air by both 
thefe methods to exhibit all the ap- 
pearance of air, fuperior in quality 
to common air; as may be feen in 
H 2 experi- 
