request that his life might be prolonged until he had compiled a statement of his results was refused; but Séguin, who was fortunately spared, undertook the task. The facts collected do not, however, bear directly on our subject, and shall not be further alluded to here.
This account of Lavoisier's researches would be incomplete without a reference to his text-book of chemistry, Traité élémentaire de Chimie, in which his views are stated in order, and with great clearness. The nomenclature current at the time was so cumbrous that it was almost, if not quite, impossible for the supporters of the new theory to express their meaning in an intelligible manner. De Morveau had suggested a nomenclature for salts; Black, too, had invented one; but neither of these systems was adapted to represent the new views. It was partly with the object of avoiding such embarrassment that Lavoisier wrote his Treatise.
He begins with a clear statement of what is generally termed "the states of matter"—solid liquid, and gaseous—and points out that solids and liquids are almost all capable of change into the aeriform state by the addition of "caloric." Proceeding next to the consideration of the
