In the month of August 1830, Reichenbach published his first memoir on the products of the destructive distillation of organic bodies, in which he described a new principle, to which he gave the name of Paraffine, as constantly occurring among those products. Not long after, in 1831, Dr Christison read before this Society a paper, in which he described a substance contained in the petroleum of Rangoon, to which he affixed the name of Petroline. On comparing the properties of these two substances, it was found that they agreed so nearly, that no doubt could be entertained that they were one and the same. As the priority of discovery rests with Dr Reichenbach, the name of Paraffine is now generally adopted. The properties of paraffine are as follows:—It is white, tasteless, inodorous, rather tough, lighter than water, fusible at 125° or 130° F., and it distils unchanged at a higher temperature. It resists the action of the strongest acids and alkalies; and, finally, when pure, it burns with a bright flame without smoke. In a second memoir published by Reichenbach in 1831, he described another of the products of destructive distillation, under the name of Eupione.