Note 99 — RESEARCH I. (continued 2)

Dr. Priestley says, “having heated iron in nitrous air, I proceeded to heat in the same air, a piece of charcoal not long after it had been subjected to a strong heat covered with sand. The sun not shining immediately, after the charcoal was introduced into the vessel of air, through the mercury by which it was confined, part of the air was absorbed; but on heating the charcoal, the quantity was increased. Having continued the progress as long as I thought necessary, I examined the air and found it to be about as much as the original quantity of nitrous air; but it was all phlogisticated air extinguishing a candle and having no mixture of fixed air in it.”—Experiments and Observations, Vol. II, page 39.