"He gives the following description of it: "The specific gravity of this air was found to differ very little from that of common air; of the two, it seemed rather lighter. It extinguished flame, and rendered common air unfit for making bodies burn in the same manner as fixed air, but in a less degree, as a candle which burnt about 80” in pure common air, and which went out immediately in common air mixed with 6/55 of fixed air, burnt about 26” in common air mixed with the same portion of this burnt air.""