Note 149 — RESEARCH I. (continued 2)

The decomposition of aëriform nitrous acid by mercury, was first noted by Priestley; vol. iii. pag. 101. This decomposition I have often had occasion to observe. In reading Humbolt’s paper on eudiometry, Annales de Chimie, xxviii, pag. 150, I was not a little surprised to find that he takes no notice of this fact. He seems to suppose that nitrous acid can remain aëriform, and even be condensed, in contact with mercury, without alteration. He says, “In mingling 100 parts of atmospheric air with 100 of nitrous air, the air immediately became red, but all the acid produced remained aëriform; and after eighteen hours some drops only of acid were formed, which swam upon themercury.”