on the Production of Dephlogijlicated Air . 
Having at length colle&ed a fufficient quantity of this air 
for that purpofe, 1 carefully removed it from the globe, and 
mixing with i meafure of it 3 meafures of nitrous air, they were 
reduced to 1,24 meafures; which fhews, that it was adtually 
dephlogijYuated air , and that of a confiderable degree of purity. 
Common air, tried at the fame time, 1 meafure of it with 
I meafure of nitrous air were reduced to 1,08 meafure. 
Having again expofed the globe with the fame water and filk 
in my window, where the fun (hone the greateft part of the 
day, at the end of three days 1 had collected 31 cubic inches 
of air, which, proved with nitrous air, gave \a-yyi— 1,18; 
that is to fay, 1 meafure of this air, added to 3 meafures of 
nitrous air, were reduced to 1,18 meafure. 
A fmall wax taper, which had been juft blown out, a fmall 
part only of the wick remaining red-hot , upon being plunged 
into a phial filled with this air, immediately took fire, and 
burnt with a very bright and enlarged flame. 
The water in the globe appeared to have loft fomething of its 
tranfparency, and had changed its colour to a very faint 
greenifh caft, having at the fame time acquired the odour or 
fragrance proper to raw filk. 
This experiment I repeated feveral times with frefh water 
(retaining the fame filk) and always with nearly the fame re- 
fult ; with this difference, however, that w r hen the fun (hone 
very bright, the quantity of air produced was not only greater, 
but its quality likewife was much fuperior to that yielded when 
the fun’s rays were more feeble, or when they w r ere frequently 
intercepted by flying clouds. The air, however, was always 
not only much better than common air, but better than the air 
in general produced by the frefh leaves of plants expofed in 
water to the fun’s rays in the experiments of Dr. Ingen- 
housz ; 
