When distilled in a retort, at a temperature above that of boiling water, or burned, as we burn it in a pipe, tobacco affords its third poison, the empyreumatic oil.  This is acrid, of a dark brown color, and having a smell as of an old pipe, in the pores of which, particularly of meerschaum clay, it may be found.  It is also narcotic and very poisonous, one drop killing reptiles, as if by an electric shock:  in this mode of action it is like prussic acid.  But this empyreumatic oil consists of two substances; for, if it be washed with acetic acid, it loses its poisonous quality.  It contains, therefore, a harmless oil, and a poisonous alkaline substance, which the acetic acid combines with and removes.  It has been shown to contain the alkaloid nicotia, and this is probably its only active component.

Assuming, therefore, that nicotianin, from its feebler action and small amount, is not a very efficient principle in producing the narcotic effects of tobacco, and that the empyreumatic oil consists only of fatty matters holding the alkali in solution, we are forced to believe that the only constituent worthy of much attention, as the very soul and essence of the plant, is the organic base, nicotin, or nicotia.

It is probable that the tobacco-chewer, by putting fifty grains of the “Solace,” “Honey-Dew,” or “Cavendish” into his mouth for the purpose of mastication, introduces at the same time from one to four grains of nicotin with it, according to the quality of the tobacco he uses.  It is not probable that anything like this amount is absorbed into the system.  Nature protects itself by salivation.  It is possible, that, in smoking one hundred grains of tobacco, there may be drawn into the mouth two grains or more of the same poison; “for, as nicotin volatilizes at a temperature below that of burning tobacco, it is constantly present in the smoke.”  It is not probable that here, again, so much is absorbed.

But we will return to this question of the relative effects of chewing, cigar- and pipe-smoking, and snuff-taking, presently.  For we suppose that the anxious mother, if she has followed us so far, is by this time in considerable alarm at this wholesale poisoning.

Poisons are to be judged by their effects; for this is the only means we have of knowing them to be such.  And if a poison is in common use, we must embrace all the results of such use in a perfect generalization before we can decide impartially.  We do not hesitate to eat peaches, though we know they owe much of their peculiar flavor to prussic acid.  It is but fair to apply an equally large generalization to tobacco.  Chemistry can concentrate the sapid and odorous elements of the peach and the bitter almond into a transparent fluid, of which the smell shall be vertiginous and the taste death.  But chemistry is often misunderstood, in two ways:  in the one case, by the incredulity of total ignorance; in the other, by the overcredulity