which, when taken in sufficient quantities into the system, produces death by paralysis. The tyro in physiology knows that death must start either from the lungs, the heart, or the nervous system. Now a narcotic is anything which, in due quantity, kills by killing the nervous system. When death is caused by too great a proportion of carbonic acid in the air, it begins at the lungs; but when it is caused by a dose of prussic acid, it begins at the medulla oblongata, the death of which causes the heart and lungs to stop acting. Prussic acid is, therefore, a narcotic; and so are strychnine, belladonna, aconite, nicotine, sulphuric ether, chloroform, alcohol, opium, thorn-apple, betel, hop, lettuce, tea, coffee, coca, hemp, chocolate, and many other substances. All these, taken in requisite doses, will kill by paralysis; and all of them, taken in lesser but considerable doses, will induce a state of the nerves known as narcosis, which is nothing more nor less than incipient paralysis. Every man who smokes tobacco, or drinks tea or coffee, until his hands are tremulous and his stomach-nerves slightly depressed, has just started on the road to paralysis: he may never travel farther on it, but he has at least turned the corner. Every man who drinks ale, wine, or spirit until his face is flushed and his forehead moist, has slightly paralyzed himself. Alcoholic drunkenness is paralysis. The mental and emotional excitement, falsely called exaltation, is due, not to stimulation, but to paralysis of the cerebrum. The unsteady gait and groping motion of the hands are due to paralysis of the cerebellum. The feverish pulse and irregular respiration are due to paralysis of the medulla oblongata. The flushed face and tremulous, distressed stomach, are due to paralysis of the sympathetic ganglia. And when a person is "dead-drunk," his inability to perform the ordinary reflex acts of locomotion and grasping is due in part to paralysis of the spinal centres. The coma, or so-called sleep of drunkenness, is perfectly distinct from true reparative sleep, being the result of serious paralysis of the cerebrum, and closely allied to delirium.5 Now, what we have stated in detail concerning alcohol is also true of tobacco. A fatal dose of nicotine kills, just like prussic acid, by paralyzing the medulla, and thus stopping the heart's beating. The ordinary narcotic dose does not produce such notable effects as the dose of alcohol, because it is hardly possible to take enough of it. Excessive smoking does not make a man maudlin, but it causes restless wakefulness, which is a symptom of cerebral paralysis, and is liable, in rare cases, to end in coma. Its action on the cerebellum and spinal cord cannot be readily stated; but its effect on the medulla and sympathetic is most notable, being seen in depression or feeble acceleration of the pulse, trembling, nausea of the stomach, and torpidity of the liver and intestines. Nearly or quite all of these effects producible by tobacco, are producible also, in even a heightened degree, by narcotic doses of tea and coffee. A concentrated dose of tea will produce a paralytic shock; and a single cup of very strong coffee is sometimes enough to cause alarming disorder in the heart's action. All these narcotic effects, we repeat, are instances of paralytic depression. In no case are they instances of stimulus followed by reaction; but whenever a narcotic dose is taken, the depressive paralytic action begins as soon as the dose is absorbed by the blood-vessels. The cheerful and maudlin drunkard is not under the action of stimulus. His rapid, irregular, excited mental action is no more entitled to be called "exaltation" than is the delirium of typhoid fever. In the one case and in the other, we have not stimulation but depression of the vitality of the cerebrum; in both cases, the nutrition is seriously impaired; in both cases, molecular disorganization of the nerve-material is predominant.
So much concerning narcotics has been established, with vast and profound learning, by Dr. Anstie. No doubt, by this time, the reader is beginning to rub his eyes and ask, Is this the way in which you are going to show that smoking is beneficial? You define tobacco as a poison which causes paralysis, and then assure us that it pays to smoke! It is true, this has at first sight a paradoxical look; but as the reader proceeds further, he will see that we are not indulging either in paradoxes or in sophisms. We wish him to take nothing for granted, but merely to follow attentively our exposition of the case. We have indeed called tobacco a poison, – and so it is, if taken in narcotic doses. We have accused it of producing paralysis, – and so it does, when taken in adequate narcotic doses. We would now call attention to a property of narcotics, which is well enough known to all physiologists, but is usually quite misapprehended or ignored by popular writers on alcohol and tobacco.6 We allude to the fact that narcotics, when taken in certain small quantities, do not behave as narcotics, but as stimulants; and that they will in such cases produce the exact reverse of a narcotic effect. Instead of lowering nutrition, they will raise it; instead of paralyzing, they will invigorate. Taken in a stimulant dose, tobacco is not only not a producer, it is an averter, of paralysis. It is not only not a poison, but it is a healthful, reparatory stimulus.
It is desirable that this point should be thoroughly understood before we advance a step farther. Here is the pons asinorum in the study of narcotics, but it must be crossed if we would get at the truth concerning alcohol and tobacco. Alcohol is a poison, says the teetotaler, who means well, but has not studied the human organism; alcohol is a poison, and once a poison always a poison. Nothing can seem more logical or reasonable, so long as one knows nothing about the subject. A quart of brandy is admitted to be poison; is not, therefore, a spoonful of brandy also poison? We reply, by no means. Physiological questions are not to be settled by formal logic. Here the quantity is the all-essential element to be taken into the account. Common salt, in large doses, is a virulent poison; in lesser doses it is a powerful emetic; in small doses it is a gentle stimulant, and an article of food absolutely essential to the maintenance of life. In the spirit of the teetotaler's logic, then, it may be asked, If a pound of salt is a poison, is not a grain of salt also a poison? We reply, call it what you please, you cannot support life without it. So from the poisonous character of the quart of brandy, the poisonous character of the spoonful is by no means a legitimate inference. The evil effects of the small dose are to be ascertained by experiment, not to be taken for granted. Logic is useful in the hands of those who understand the subject they reason about; but in other hands it sometimes leads to queer results. It was logic that used up the one-hoss shay.
The general principle to guide us here is that of Claude Bernard, that whatever substance or action, in due amount, tends to improve nutrition, may, in excessive amount, tend to damage nutrition. In the vast majority of cases the difference between food and poison, between beneficent and malignant action, is only a difference of quantity. Oxygen is the all-important stimulus, without which nutrition could not be carried on for a moment. It constitutes about one-fifth of our atmospheric air. Let us now step into an atmosphere of pure oxygen, and we shall speedily rue such a radical proceeding. We shall live so fast that waste will soon get ahead of repair, and our strength will be utterly exhausted. The effect of sunlight on the optic nerve is to stimulate the medulla, and increase thereby the vigor of the circulation. But too intense a glare produces blindness and dizziness. The carpenter's thumb, by friction against the tools he uses, becomes over-nourished and tough; but if the friction be too continuous, there is lowered nutrition and inflammation. Moderate exercise enlarges the muscles; exercise carried beyond the point of fatigue wastes them. The stale prize-fighter and the overworked farmer are, from a physical point of view, pitiable specimens of manhood. A due amount of rich food strengthens the system and renders it superior to disease; an excessive amount of rich food weakens the system, and opens the door for all manner of aches and ailments. A pinch of mustard, eaten with meat, stimulates the lining of the stomach, and probably aids digestion; but a mustard poultice lowers the vitality of any part to which it is applied. Moderate emotional excitement is a healthful stimulus, both to mind and body; but intense and prolonged excitement is liable to produce delirium, mania, or paralysis. Ne quid nimis, therefore, the maxim of the wise epicurean, is also the golden rule of hygiene. If you would keep a sound mind in a sound body, do not rush to extremes. Steer cautiously between Scylla and Charybdis, and do not get wrecked upon the one or swallowed up in the other.
Few persons who have not been specially educated in science have ever learned this great lesson of Materia Medica, "that everything depends on the size of the dose." It is not merely that a small dose will often produce effects differing in degree from those produced by a large dose; nor is it merely that the small dose will often produce an effect differing in kind from that of the large dose; but it is that the small dose will often produce
Sleep is caused by a diminution of blood in the cerebrum; stupor and delirium, as well as
Mr. Lizars (On
