2l6 ] 



with this obfervation, that burned air is farther 

 dimininifhed both by putrefaction, and a mixture 

 of iron filings and brimftone; and I therefore, 

 take it for granted, by every other caufe of the 

 diminution of air. It is probable, therefore, that 

 burned air is air fo far loaded with phlogifton, as 

 to be able to extinguish a candle, which it may 

 do long before it is fully fatu rated. 



Inflammable air with a mixture of nitrous air 

 burns with a green flame. This makes a very 

 pleating experiment when it is properly conducted. 

 As, for fome time, I chiefly made ufe of copper 

 for the generation of nitrous air, I firft afcribed 

 this circumftance to that property of this metal, 

 by which it burns with a green flame ; but I was 

 prefently fatisfled that it muft arife from the fpirit 

 of nitre, for the effect is the very fame from which- 

 ever of the metals the nitrous air is extracted, all 

 of which I tried for this purpofe, even filver and 

 gold. A mixture of oil of vitriol and fpirit of 

 nitre in equal proportions diflblved iron, and the 

 produce was nitrous air; but a lefs degree of fpirit 

 of nitre in the mixture produced air that was in- 

 flammable, and which burned with a green flame. 

 It alfo tinged common air a little red, and dimi- 

 nifhed it, though not much. 



The diminution of common air by a mixture of 

 nitrous air, is not fo extraordinary as the diminu- 

 tion which nitrous air itfelf is fubject to from a 

 mixture of iron filings and brimftone, made into a 

 pafte with water. This mixture, as I have already 

 obferved, diminifhes common air between one 

 fifth and one fourth, but has no fuch effect upon 

 7 any 



