z 1 8 Analyfts of the Airl 
4th Of a cubick inch of filings of Jrony 
and a cubick inch of Limon juice^ abler bed 
two cubick inches of air. 
. It is remarkable, that the fame mixtures 
fhould change from generating to abforbing, 
and from abforbing to generating ftates j 
fometimes with, and fometimes without any 
fenfible alteration of the temperature of the 
air. 
Experiment XCV. 
Half a cubick inch of fpirits of Harts- 
horn y with filings of Iron abforbed i i 
cubick inches of air, with filings of Copper 
double that quantity of air, and made a 
very deep blue tinfture, which it retained 
long, when expofed to the open air. It was 
the fame with fpirit of Sal Ammoniacy and 
filings of Copper. 
" A quarter of a cubick inch of filings of 
Irony with a cubick inch of powdered Brim- 
fionSy made into a pafte with a little water, 
abforbed 19 cubick inches of air in two days. 
N. B. I poured hot water into the ciftern x Xy 
(fig* 34*) to promote the ferment. 
A like 
