<5 n the /pacific Gravities, Ac. of Saline Subfiances. 21 1 
tn inflammable air , and alfo formed a phofphorus ; and that he 
has little doubt but that he {hall be able to produce any thing 
elfe in which phlogifton is fuppofed to be concerned. This, he 
fays, agrees with feveral of his former experiments, efpecially 
that in which he produces inflammable air from alkaline air, 
by means of the ele&ric fpark and volatile alkali from iron, 
fuperfaturated with phlogifton by means of nitrous air, which 
he has repeatedly done fince the publication of his lad: volume. 
This obfervation, he adds, may help to explain fome things in 
the theory of chemiftry, efpecially the affinity which all acids 
have both with phlogifion and with alkalies ; but, he fays, that 
alkaline air contains fomething elfe befides phlogifton ; becaufe 
when this air is ufed, there is always a refiduum of fomething 
that is neither alkaline nor inflammable air ; but he wants more fun- 
fhine to complete and extend his experiments on this fubjeft *. 
OF THE QUANTITY OF PHLOGISTON 
IN NITROUS AIR. 
100 gr. of filings of iron being difl'olved in a fufficient quan- 
tity of very dilute vitriolic acid produced, with the afliftance of 
heat gradually applied, 155 cubic inches of inflammable air, 
the barometer at 29,5, and the thermometer between 50 and 
6o°. Now inflammable air and phlogifton being the fame 
thing, this quantity of inflammable air amounts to 5,42 gr. of 
' phlogifton. 
Again, 100 gr. of iron, difl'olved in dephlogifticated nitrous 
acid, in a heat gradually applied and raifed to the utmoft, afford 
83,87 cubic inches of nitrous air. And as this nitrous air con- 
Hs Since this paper was committed to the piefs, I find t h n. t IMi. pelletiek has 
reduced the arfenical acid to a regulus, by merely paffing inflammable air through 
the folution of that acid in twice its weight of water, noz. Journ. February 1782. 
E e 2 tains 
