1 34 Mr. Kirwan # s Experiments 
twenty-four hours more, I examined the refiduary air. It 
exhibited the following appearances. 
i°, It had the fmell of alkaline air pretty ftrongly; at Ieaft 
that fmell iffued from the jar that contained it after the air 
itfelf was poured into another jar. 
2°, A candle burned in it naturally. 
3°, It did not affedt tindture of litmus or lime-water, or ace* 
tons barytes. 
4°, No fpecies of air had any effedt on it except the dephlo* 
gifticated, with which it produced a flight redneis and dimi- 
nution. 
5°, It produced a flight white precipitate in folution of 
filver. 
It is plain, this air is the fame as that which Di% Priest* 
ley calls dephlogijlicated nitrous air , and which, I think, may 
more properly be called deacidified nitrous air . A further exa- 
mination of it would lead me too far from the prefent fubjedt : I 
fhall therefore defer it until another opportunity. 
As it appeared to me, from the experiment mentioned in the 
fecond fedtion (in which I found fulphur precipitated from a 
mixture of nitrous and hepatic air, immediately after the ad- 
miffion of common air) that an uncombined acid in the nitrous 
air was the caufe of the precipitation of fulphur ; I attempted 
depriving nitrous air of any loofe acid it might contain, before 
I fliould mix it with hepatic air. 
ifl, I made fame nitrous air from filver very carefully over 
boiled and filtered water, and found it to contain an acid, for it 
ftrongly reddened tindture of litmus. 
2dly, I admitted alkaline air to this nitrous air until it no 
longer caufed any cloud, and then wafhed out the ammoniacal 
compound in diftilled water ; after which I transferred this 
3 purified 
