V. Researches regarding the molecular constitution of the volatile organic bases

Abstract The limited number of elementary substances which are concerned in the elaboration of the endless variety of organic compounds, long ago directed the course of chemical inquiry into the channel of speculations as to the mode in which the various constituents are grouped in bodies of this nature. The necessity of these speculations became more and more imperative as the boundary of the science extended; they were indeed forced upon us by the discovery of substances isomeric with each other which deprived us of the resort to mere quantity for the explanation of their contrasting qualities. Wild and incongruous though some of the views, proposed from time to time, may have been, it must be admitted that their influence upon the progress of chemistry has been most beneficial; especially in the organic department of this science, it is to the theory of the compound radicals, the result of these speculations, that we are indebted for the light which now begins to dawn upon the chaos of collected facts, even if we should never succeed in isolating these radicals. Among the various classes of organic substances, there is perhaps none of which, from an early period, chemists have so constantly endeavoured to attain a general conception as the group of compounds which have received the name of organic bases, all—and they are now very numerous—being capable of combining, like the metallic oxides, with acids, and being derived either from vital processes in animals or plants, or from a variety of artificial reactions conducted in the laboratory.