Part 3

[16] "The origin of the belief that stimulation is necessarily followed by a depressive recoil is obviously to be found in the old vitalistic ideas. It is our old acquaintance, the Archæus, whose exhaustion, after his violent efforts in resentment of the goadings which he has endured, is represented in modern phraseology by the term 'depressive reaction.' This idea once being firmly established in the medical mind, the change from professed vitalism to dynamical explanations of physiology has not materially shaken its hold." Id. p. 146. An interesting example of the way in which quite obsolete and forgotten theories will continue clandestinely to influence men's conclusions. The subject is well treated by Lemoine, _Le Vitalisme et l'Animisme de Stahl_. Paris, 1864.

[17] "From good wine, in moderate quantities, there is no reaction whatever."--Brinton, _Treatise on Food and Digestion_.

Let us not, however, indulge in sweeping statements. We have expressed ourselves with caution, but a still further limitation needs to be made. There are a few persons who are never stimulated, but always poisonously depressed, by certain particular narcotics. There are a few persons--ourselves among the number--in whom a very temperate dose of coffee will often give rise to well-defined symptoms of narcosis. There are others in whom even the smallest quantity of alcoholic liquor will produce giddiness and flushing of the face. And there are still others upon whom tobacco, no matter how minute the dose, acts as a narcotic poison. But such cases are extremely rare; and it is needless to urge that such persons should conscientiously refrain, once and always, from the use of the narcotic which thus injuriously affects them. Our friendly challenge, above given, is addressed to the vast majority of people; and thus limited, it may be allowed to stand.

We have now defined a narcotic; we have seen that narcotics, in certain doses, will act as stimulants, and we have defined a stimulant. Until one's ideas upon these points are rendered precise, there is little hope of understanding the ordinary healthy action either of tobacco or of alcohol. But the reader who has followed us thus far will find himself sufficiently prepared for the special inquiry into the stimulant effects of these substances. Confining ourselves, for the present, to tobacco, we shall find that by assisting the nutritive reparatory process, it conforms throughout to the definition of a true stimulant.

What do we do to ourselves when we smoke a cigar or pipe? In the first place, we stimulate, or increase the normal molecular activity of, the sympathetic system of nerves. By so doing we slightly increase the secretion of saliva, and of the gastric,[18] pancreatic, and intestinal juices. We accomplish these all-important secretory actions with a smaller discharge of nerve force: we economize nerve force in digestion. And by this we mean to say that we perform the work of digesting food just as well as before, and still have more of the co-ordinating and controlling nerve-power left with which to perform the other functions of life. Thus at the outset tobacco exhibits itself as an _economizer of life_. Such is the inevitable inference from its stimulant action on the sympathetic. From the distribution of the sympathetic fibres, we deem it a fair inference that the bile-secreting function of the liver is also facilitated; but of this there is less direct evidence.[19] We can now understand why a pipe or cigar dissipates the feeling of heaviness ensuing upon a dinner, or other hearty meal; and when we recollect how instant is the relief, we can form some notion of the amount of nerve-force which is thus liberated from the task of digestion. We are thus also reminded of the hygienic rule that smoking must be done after eating, and not, in ordinary cases, upon an empty stomach. If we smoke when the stomach is empty and quiescent, the stimulated secretion of the alimentary juices is physiologically wasteful; and, moreover, the much more rapid absorption of nicotine by the blood-vessels increases the liability to narcotic effects. It is upon this very principle that the same amount of wine may stimulate at dinner, but narcotize when taken in the forenoon.

[18] "It is a positive fact that the gastric secretion can at any time be produced by simply stimulating the salivary glands with tobacco."--Lewes, _Physiology of Common Life_, vol. i. p. 192. The gastric secretion is also stimulated by the action of tobacco on the pneumogastric or eighth pair of nerves.

[19] A possible means of testing this inference would be the judicious employment of smoking as a dietetic measure in cases of jaundice. This distressing disease occurs when the torpid liver secretes too little bile. The biliverdine, which would ordinarily be taken up to make bile, remains in the blood until, seeking egress through the sweat-glands, it colours the skin yellow. In the case of novices, however, great care would need to be taken; as unskilful smoking is very likely to induce narcosis.

Thus far we find tobacco to be a friend and not an enemy. Now, in the second place, when we smoke, we stimulate the medulla oblongata, and through this we send a wave of stimulus down the pneumogastric nerve, and this makes the heart's action easier. One of the earliest stimulant effects of tobacco to be noted is the slightly increased frequency and strength of the pulse.[20] A narcotic dose produces quite the opposite effect. It begins by greatly increasing the frequency while diminishing the strength, so as to make a feeble, fluttering pulse; and it ends by reducing the frequency likewise. After some years of temperate smoking we accidentally felt, for the first time, the narcotic effects of tobacco. Eight or nine cigars (large twenty-cent ones, such as Mr. Parton delights in the recollection of) smoked consecutively while taking a cold midnight drive, were followed by unmistakable symptoms of narcosis. Along with the muscular tremour of the stomach, much more acute than that of ordinary nausea, it was observed that the pulse, normally strong and regular at 80, had been reduced to 69, and was feeble and flickering. Similar, no doubt, are the symptoms which ordinarily worry the novice, in whom acute narcosis is liable to result from the lack of skill with which he draws in too large a quantity of the narcotic constituents of his cigar. The effects of tobacco, through the medulla and pneumogastric, upon the heart, are among its most notable effects. A dose of pure nicotine stops the heart instantly, a narcotic dose interferes with its action, but a stimulant dose facilitates it. The same results are attainable by means of electricity.[21] A powerful current through the pneumogastric of a frog or rabbit will stop the heart, a less powerful current will slacken it, a slight current will somewhat accelerate it. Emotional effects are precisely similar. Sudden overwhelming joy or sorrow may operate as a true narcotic, arresting the heart's contractions, while steady diffusive pleasure always facilitates them.

[20] See a paper by Dr. E. Smith, read before the British Association in 1862.

[21] See an admirable paper by Lewes in the _Fortnightly Review_, May 15th, 1865.

The stimulant action of tobacco upon the heart is precisely the same as that of sunlight, which, by inciting the nervous expanse of the retina, indirectly strengthens and accelerates the pulse. So far as the circulation is concerned, there is no difference between the two. The one stimulus may indeed be popularly called "natural," while the other is called "artificial," but such a distinction is physiologically meaningless. The molecular action is the same and the consequences to the organism are the same in both cases. The heart's normal action being facilitated, the blood is poured more vigorously through every artery, every vein, and every network of capillaries. Every tissue receives with greater promptness its quota of assimilable nutriment. And, the web-like plexuses of nerve-fibres distributed throughout the tissues being simultaneously stimulated, the work of nutrition goes on with enhanced vigour and efficacy. Nor is it possible for the excreting organs to escape the influence. Lungs, skin, and kidneys must be alike incited; and the removal from the blood of noxious disintegrated matters, the products of organic waste, is thus hastened.

So much is to be inferred from the stimulant action of tobacco upon the medulla. Of all this complicated benefit, the brain receives perhaps the largest share. The brain receives one-fifth, or according to some authorities one-third, of all the blood that is pumped from the heart. More than any other organ it demands for its due nutrition a prompt supply of arterial blood; and more than any other organ it partakes of the advantages resulting from vigorous circulation.

The stimulant action of tobacco upon the spinal cord and the cerebral hemispheres is less conspicuous. Yet even here its familiar influence in stilling nervous tremour and allaying nocturnal wakefulness is good testimony to its essentially beneficent character. Wakefulness and tremour are alike symptoms of diminished vitality; and the agent which removes them is not to be called, as Mr. Parton in his mediæval language calls it, "hostile to the vital principle."

So much for the net results of the stimulant action of tobacco. So far we have travelled on firm ground, and we have not found much to countenance Mr. Parton's view of the subject. But now some curious inquirer may ask, what _is_ this stimulant action? What is the physiological expression for it, reduced to its lowest terms? Here we must keep still, or else venture upon ground that is very unfamiliar and somewhat hypothetical. There is no help for it; for we cannot yet give the physiological expression for unstimulated nervous action, reduced to its lowest terms. We know what kind of work nerves perform, but how they perform it we can as yet only guess. Nor, as far as the practical bearings of our subject are concerned, does it matter whether this abstruse point be settled or not. Still, even upon this dark subject recent research has thrown some gleams of light. A nerve-centre is a place where force is liberated by the lapse of the chemically-unstable nerve-molecules into a state of relative stability.[22] To raise them to their previous unstable state, thereby enabling them to fall again and liberate more force, is the function of food. Now our own hypothesis is, that tobacco and other narcotic stimulants enable force to be liberated by the isomeric transformation of the highly complex nerve-molecules, which retain in the process their state of relative instability, and are thus left competent to send forth a second discharge of force without the aid of food.

[22] We fear that this explanation will be rather unintelligible to the general reader. But it is hardly practicable for us to insert here a disquisition on physiological chemistry. Those who are familiar with modern physiology will readily catch our meaning. Those who are not may skip, if they choose, this parenthetical paragraph.

In support of this hypothesis we have the well-known fact that tobacco, like tea, coffee, alcohol and coca, universally retards organic waste. These substances effect this result in all the tissues, and more especially may they be expected to accomplish it in nervous tissue, where their action is so conspicuously manifest.

Thus is explained the familiar action of narcotic-stimulants in relieving weariness. Weariness, in its origin, is either muscular or nervous. It implies a diminution--owing to failing nutrition--of the total amount of contractile or of nervous force in the organism; and it shows that the weary person must either go to sleep or eat something. Now every one knows how a cup of tea, a glass of wine, or a cigar, dispels weariness. Of the three agents, tobacco is perhaps the most efficacious, and it can produce its effect in only one way--namely, by economizing nervous force, and arresting the disintegration of tissue.

Thus also is explained the marvellous food-action of these substances. Tea and coffee enable a man to live on less beefsteak. The Peruvian mountaineer, chewing his coca-leaf, accomplishes incredibly long tramps without stopping to eat. And every hardy soldier, in spite of Mr. Parton, has that within him which tells him that he can better endure severe marches and wearisome picket-service if he now and then lights his pipe. The personal experience of any one man is, we are aware, not always conclusive; but our own, so far as it goes, bears out the general conclusion. It was when we were engaged in severe daily mental labour, that we first conceived the idea of employing tobacco as a means of husbanding our resources. Narcosis being steadily avoided, the experiment was completely, even unexpectedly, successful. Not only was the daily fatigue sensibly diminished, but the recurrent periods of headache, gloom, and nervous depression were absolutely and finally done away with. That this result was due to improved nutrition was shown by the fact that, during the first three months after the habit of smoking was adopted, the average weight of the body was increased by twenty-four pounds--an increase which has been permanent. No other dietetic or hygienic change was made at the time, by which the direct effects of the tobacco might have been complicated and obscured.

The statement that smoking increases the average weight of the body[23] is not, however, universally true. We have here an excellent illustration of the impracticability of laying down sweeping rules in physiology. Many persons find their weight notably diminished by the use of tobacco; and we frequently hear it said that smoking will not do for thin people, although for those who are fleshy it may not be injurious. In this there is a very natural but very gross confusion of ideas, which a little reflection upon the subject will readily clear up. It is true that moderate smoking sometimes increases and sometimes diminishes the weight; and it is no less true that in each case the result is the index of heightened nutrition! This seems, of course, paradoxical. But physiology, quite as much as astronomy, is a science which is constantly obliging us to reconsider and rectify our crude off-hand conceptions.

[23] "Tobacco, when the food is sufficient to preserve the weight of the body, increases that weight, and when the food is not sufficient, and the body in consequence loses weight, tobacco restrains that loss." Hammond, _Physiological Effects of Alcohol and Tobacco_, Am. Journal of Medical Sciences, tom. XXXII. N.S., p. 319.

It is by no means true that increase of the tissues in bulk and density is always a sign of improved health. We are accustomed to congratulate each other upon looking plump and rosy. But too much rosiness may be a symptom of ill-health; and, similarly with plumpness, there is a point beyond which obesity is a mere weariness to the spirit. Nor does a person need to become as rotund as Wouter Van Twiller in order to reach and pass this point. Many persons, who are not actually corpulent, would lose weight if their nutrition could be improved. And the explanation is quite simple.

Normal nutrition is not merely the repair of tissue: it is the repair of all the tissues in the body _in due proportion_. This is a very essential qualification. Fibrous and areolar tissue, muscle, nerve, and fat are daily and hourly wasting in various degrees; and the repair, whether great or small, must be nicely proportioned to the waste in each tissue. If a pound is added to the weight of the body, it makes all the difference in the world whether one ounce is muscle, another ounce nerve, a third ounce fat, and so on, or whether the whole pound is fat. When one tissue gets more than its fair share, the chances are that all the others must go a-begging. The co-ordinating, controlling power of the organism over its several parts is diminished,--which is the same as saying that nutrition is impaired. Evidence of this soon appears in the circumstance that the deposit of adipose tissue is no longer confined to the proper places. Fat begins to accumulate all over the body, in localities where little or no fat is wanted, and notably about the stomach and diaphragm, causing laborious movement of the thorax and wheezing respiration. When a man gets into this state, it is a sign that the ratio between the waste and the repair of his tissues has become seriously dislocated. You can relieve him of his fat only by improving his nutrition. The German who drinks his forty glasses of lager bier _per diem_ is said to be bloated; and we have heard it gravely surmised that the ale, getting into his system, swells him up--as if the human body were a sort of bladder or balloon! The explanation is not quite so simple. But it is easy to see how this immense quantity of liquid, continually loading the stomach and intestines, and entailing extra labour upon all the excreting organs, should so damage the assimilative powers as to occasion an excessive deposit of coarse fat and of flabby, imperfectly-elaborated connective tissue, over the entire surface of the body. And the state of chronic, though mild, narcosis in which the guzzler keeps himself, by still further injuring his reparative powers, contributes to the general result.

There are consequently four ways in which tobacco may exhibit its effects upon the nutrition of the body.

I. In stimulant doses, by improving nutrition, it may increase the normal weight.

II. In stimulant doses, by improving nutrition, it may cause a diminution of weight abnormally produced.

III. In narcotic doses, by impairing nutrition, it may cause emaciation.

IV. In narcotic doses, by impairing nutrition, it may aggravate obesity instead of relieving it.[24]

[24] In this exposition we have assumed that the tobacco is smoked and the saliva retained. If the saliva be frequently ejected, the case is entirely altered. Habitual spitting incites the salivary glands to excessive secretion, thereby weakening the system to a surprising extent, and probably lowering nutrition. Many temperate smokers, who think themselves hurt by tobacco, are probably hurt only because, though in all other respects gentlemen, they will persist in the filthy habit of spitting. There is no excuse for the habit, for with very little practice the desire to get rid of the saliva entirely ceases, and is never again felt.

In chewing, the saliva is so impregnated with the nicotinous constituents of the leaf, that the choice lies far more narrowly between spitting and narcosis. Of the two evils we shall not venture to say which is the least. In snuffing, too, the question is complicated by the acute local irritation caused by the contact of the stimulant with the nasal membranes. This, no doubt, has its medicinal virtues. But for a healthy man it is probable that smoking is the only rational, as it is certainly the only decent, way in which to use tobacco.

We may see, by this example, how much room is always left for fallacy in the empirical tracing of physiological effects to their causes. The phænomena are so complex that induction is of but little avail, unless supported and confirmed by deduction.[25] In the case of tobacco, our conclusions are so confirmed. Deduction, supported by cautious induction, shows the stimulant action of tobacco to be of permanent benefit to the system; and hence the statements of those smokers who believe themselves injured by the habit must be received with due qualifications. Yielding unsuspiciously to the influence of a prejudice which originated in an absurd puritanical notion of "morality,"[26] many smokers are in the habit of reviling the practice which they nevertheless will not abandon. Having once begun to smoke, they persist in laying to the account of tobacco sundry aches and ails which in the hurry and turmoil of modern life no one can expect wholly to escape, and many of which are such as tobacco could not possibly give rise to. If their teeth, for instance, begin to decay, tobacco gets the blame, although it is notorious to dentists that tobacco preserves the enamel of the teeth as hardly anything else will. We have seen teeth which had been kept for months in a preparation of nicotine and were in excellent condition. Then the headache, due perhaps to an overdose of hot risen biscuit or viands cooked in pork-fat, is quite likely to be laid to the charge of the general scape-goat; although to produce a headache directly by means of tobacco requires a powerful narcotic dose.[27] One of the chief causes of ordinary headache is doubtless the use of the execrable anthracite which Pennsylvania protectionists force upon us by means of their unrighteous prohibitory tariff upon English coal.[28] We have even heard it alleged that smoking impairs the eyesight. Students smoke much, and are nearsighted, is the complacent argument--it being apparently forgotten that sailors smoke much and are far-sighted, and that in each case the result is due to the way in which the eyes are used.

[25] Mill's _System of Logic_, 6th ed. vol. I. pp. 503-508.

[26] "The Puritans, from the earliest days of their 'plantation' among us, abhorred the fume of the pipe." Fairholt, _Tobacco, its History, etc._, p. 111.

[27] Smoking has also been charged with acting as a predisposing, or even as an exciting, cause of insanity,--a notion effectually disposed of by Dr. Bucknill, in the _Lancet_, Feb. 28th, 1857.