I have a flock of India pigeons which have been in-bred for fifteen years to my own knowledge, and apparently with no deterioration. They are still strong, vigorous, and prolific.

There is a herd of wild cattle now in the Chillingham Park, England, which has been confined there for several hundred years, and strictly isolated.

No new strains have been introduced, and the herd still remains hardy and healthy.

On the other hand, there exists a general impression among physicians, based upon experience and observation of a general character, that marriages of consanguinity result, more often than other marriages, in unfavorable effects upon offspring; and the statistics collected by Dr.

Bemis and others appear, on first examination, to confirm such conclusions.

The majority of farmers and stock-breeders in this country act upon the theory that it is important and, indeed, necessary, in order to maintain herds and flocks in a healthy condition, to frequently introduce other strains of blood; and the farmer who should fail to do this in reference to his cattle, his swine, and fowls, would be ent.i.tled to little sympathy in case his animals should degenerate in any measure physically, or become less prolific.

Now, the well-established principles of heredity appear to confirm, in a general way, both these views. The qualities of parents whether healthy or unhealthy are transmitted to offspring; and if all herds of cattle and swine and flocks of fowls were in a strictly healthy condition, there would exist no reasons why they might not remain so indefinitely, so far as interbreeding is concerned.

The conditions of animal life, however, under the influence of civilization, are certainly more unfavorable to health than when in a native condition. This is especially true of those cla.s.ses upon which we depend for labor. The change from animal life on the broad prairies and woods of a temperate zone, to life in stables of crowded cities and yards of farmers, many of which are in any thing but a sanitary condition, and to the experience of daily exposure and labor, and ofttimes to ill treatment and improper food, induces disease no less surely among animals than among the human race.

If either men or animals were in a condition of perfect health, there would be no unfavorable results from marriages of consanguinity, or other marriages, as there would exist no imperfections, either physical or mental, to be transmitted. No such persons, however, are found. All are tainted with the seeds of disease to a greater or less extent, and health is a question of degree. If, now, two persons of a phthisical or insane diathesis contract marriage, the tendency toward such a diathesis will be greatly increased in the offspring. If this tendency in each parent be represented by two, then it will be two multiplied by two in the offspring, except so far as it may be modified through the influence of atavism. This would be the case without reference to the question of consanguinity.

But blood-relatives are vastly more likely to inherit a similar diathesis--indeed, are quite sure to do so, if it be one of unhealthy character,--and the atavic influences would also be similar; so that any counteracting effect through this influence would be much less between blood-relations than with others, and would probably be the greatest when no such relation exists.

Here, then, becomes apparent the danger arising from consanguineous marriages, _i. e._, that of perpetuating and intensifying unfavorable physical and mental traits, which may be alike on both sides. Where no such relation exists, there is a great probability that other counteracting qualities of character and hereditary influences may modify and even remove weaknesses, while, with such a relation existing, there is every probability that weaknesses or tendencies toward disease, both physical and mental, whether inherited or acquired, will become greatly increased.

Therefore, as there exist in many families, undesirable traits of character, both physical and mental, a removal or diminution of which is desirable; and as there is a greater probability that this can be more surely done, of whatever nature they may be, by introducing other and opposing tendencies from unrelated families, it would appear to be highly important, as a rule, to discountenance marriages of persons who are related to each other by ties of blood.

CHAPTER X.

ALCOHOL.

Of the several individual factors, which are especially potent, as tending to develop and perpetuate the Insane Diathesis, there are none which can be regarded as more influential, either directly or indirectly, than alcohol. Over-education of the brain, under-education, and heredity, all may exert an influence which tends toward this result, and their victims may be found in large numbers in all our asylums and hospitals; but the effects of alcohol are so insidious, it has been so generally used in the past, and its effects are so often transmitted to succeeding generations, that probably the sum total of its effects are far greater than those of either of the above-named agencies.

I therefore regard it as a happy omen for the future of society, that the physiological effects of this substance, and its absolute uselessness and positive injury to the human system, except as a medicine and under exceptional circ.u.mstances, are beginning to be more clearly recognized by the medical profession, and more generally understood by the educated portion of society. And yet I fear we are far from the realization of any millennial period, as to its use and abuse, in this or other countries.

Indeed, while probably there is much less of alcohol used as a beverage among the more intelligent portion of the community at the present time than there was fifty years ago, yet I think there is more used in that way among the operative cla.s.ses, and especially the young of large towns and cities. The facilities of obtaining it are so much greater, that the temptations to its use are greatly increased, and the habit of using lager beer, ale, and wine, among those from fourteen to twenty-four or twenty-six years of age, is certainly greatly increased, if the numbers of this cla.s.s who frequent and a.s.sist in sustaining the large number of saloons and public-houses now so prevalent in cities, may be taken as an indication of existing facts.

Granting, however, that actually less of alcohol is now consumed than formerly, per capita, it by no means follows that the amount of its evil effects is less. The conditions of life are so greatly different to-day from those existing fifty years ago; populations reside to a so much larger extent in-doors, so that alcohol would be much less freely and easily eliminated from the system, than when exercising and breathing in an out-of-door atmosphere; life is so much more intense in many of its avocations which were then unknown, necessitating very much larger drafts upon the brain and nervous system; the means with which to purchase and use alcoholic beverages by the laboring cla.s.ses are so much more abundant and easily obtained now than formerly, and while living in places of larger population than would be possible if residing in the country, or in small villages,--all these conditions and others unite in rendering the probability of its use greater, and its effects upon the nervous system vastly more injurious than formerly. Under these conditions of modern civilization a small quant.i.ty goes a long way. Besides, society is to-day reaping the harvest of its abuse of this drug during a long period, in the shape of a diathesis which manifests itself in various ways and under many forms of disorder.

Some years since I had occasion to examine the history of admissions to the Retreat, which at that time amounted to more than five thousand cases, and it was found that in more than one tenth of these cases the cause of insanity had been traced to the use of alcohol. This, however, did not embrace those cases which had inherited an unstable condition of brain in consequence of the use of alcohol by parents, and became insane for this reason.

Of the sixteen hundred insane and imbecile or feeble-minded persons in Connecticut at the present time, it is estimated that not less than one fifth have become so either directly or indirectly through the influence of alcohol. Some writers estimate the amount of insanity which is caused through the influence of alcohol, on parents and their children, in England, at a much higher proportion, than this. Statistics indicate that a considerably larger amount of spirits, beer, and wine, per capita, is used yearly in Great Britain than in the United States.

My present purpose, however, is to draw attention to the part it plays, more particularly when used not immoderately as a beverage (if any use of it as such can be so characterized), in creating a diathesis which renders the brain liable to unstable and irregular action. And I may remark at the outset that it does not so much signify in what form of beverage it may be used. The _quant.i.ty_ taken is the important point--whether it be in the form of beer or wine, brandy or whiskey. The alcohol contained in any or all of these articles is _the_ thing sought for, and _its_ influence upon the brain is that of paramount importance and consideration.

In order that we may more clearly understand the manner in which the use of alcohol, in its various forms, as a beverage, tends to create an unstable condition of the nervous system and irregular mental activity, it becomes necessary to study, in some measure, its physiological effects upon the system, as they have been demonstrated by means of experiments conducted with scientific accuracy. This becomes the more necessary, as there has always existed, and still exists, in the public mind a firm belief that its effects are quite harmless, and may be even beneficial, _if it is used in moderation only_.

I. That the primary physiological effects of alcohol upon the nervous system are such as to cause, either directly or indirectly, a large increase of some of the functional activities of the body, has always been so well known, that alcohol has long been regarded as one of the most active stimulants. Hence its so general use in medicine. And yet, to how great an extent it acts as such, and how much is physiologically signified by its effects as a stimulant, especially upon the primary tissues of the body, has not been so well understood. That this may be rendered more clear in the mind of the reader, I shall now introduce some of the results of experiments conducted by Dr. Parkes and Count Wollowicz. These experiments were upon the person of a strong and healthy young man, and were intended to be as accurate as possible. They extended over two periods: the _water period_ and the _alcohol period_, and were continued many days in succession. During the first period, the person used no other fluid than water, and the action of the heart was registered at regular intervals, a mean of the several registrations being taken as a basis for computation.

The same plan was followed during the alcohol period, and during the days while increased amounts of alcohol were administered. I herewith give the results in the words of their own report:

"The highest of the daily means of the pulse observed during the first, or water, period, was 77.5; but on this day two observations were deficient.

The next highest daily mean was 77 beats.

"If, instead of the mean of the eight days, or 73.57, we compare the mean of this one day, viz., 77 beats per minute, with the alcoholic days, so as to be sure not to over-estimate the action of the alcohol, we find:

"On the 9th day, with one fluid ounce of alcohol, the heart beat 430 times more.

"On the 10th day, with two fluid ounces, 1,872 times more.

"On the 11th day, with four fluid ounces, 12,960 times more.

"On the 12th day, with six fluid ounces, 30,672 times more.

"On the 13th day, with eight fluid ounces, 23,904 times more.

"On the 14th day, with eight fluid ounces, 25,488 times more.

"But as there was ephemeral fever on the 12th day, it is right to make a deduction, and to estimate the number of beats on that day as midway between the 11th and 13th days, or 18,432. Adopting this, the mean daily excess of beats during the alcoholic days was 14,492, or an increase of rather more than 13 per cent.

"The first day of alcohol gave an excess of 4 per cent., and the last of 23 per cent.; and the mean of these two gives almost the same percentage of excess as the mean of the six days.

"Admitting that each beat of the heart was as strong during the alcoholic period as in the water period (and it was really more powerful), the heart on the last two days of alcohol was doing one fifth more work.

"Adopting the lowest estimate which has been given of the daily work done by the heart, viz., as equal to 122 tons lifted one foot, the heart, during the alcoholic period, did daily work in excess equal to lifting 15.8 tons one foot, and in the last two days did extra work to the amount of 24 tons lifted as far.

"The period of rest for the heart was shortened, though, perhaps, not to such an extent as would be inferred from the number of beats; for each contraction was sooner over. The heart, on the fifth and sixth days after alcohol was left off, and apparently at the time when the last traces of alcohol were eliminated, showed, in the sphygmographic tracings, signs of unusual fulness; and, perhaps, in consequence of this, when the brandy quickened the heart again, the tracings showed a more rapid contraction of the ventricles, but less power than in the alcoholic period. The brandy acted, in fact, on a heart whose nutrition had not been perfectly restored."[16]

In reference to the result of the above experiments, it will be observed that no special notes are made except in relation to the action of the heart. The primary effect of alcohol is upon this organ, through its influence upon the nervous system. It, however, by no means ends here, but through it extends to all other portions of the body.

Now, the heart (and all other organs of the system) may be said to have a unit of power--so much, and no more inherent strength of action; so much capacity of function. If, therefore, under the influence of alcohol or any other drug, an organ is made to do two hours' work in one, or in any measure an increase of its normal activity is secured, a draft is made upon its _reserve_ power, and, that it may regain this, there must necessarily afterward occur a period of so much less than normal activity.

In other words, what has been gained in action under the effect of stimulus, must be lost on its withdrawal, and there must ensue a period of feeble and imperfect action, which is radiated to all other portions of the system, and is manifest in none more fully than in the brain. Indeed, upon the action of the heart as to frequency and regularity, depends the action of the brain as to continuity and strength of thought; and this, in even a greater measure than in relation to the functions of other parts.

The brain at all times contains a much larger portion of the blood than any other organ, and this quant.i.ty is imperatively necessary to its normal action as to thought. To such an extent is this so, that consciousness at once fades into darkness, and all thought ceases instantaneously, upon the check of its circulation, even in certain limited areas of its surface.

We therefore perceive how even more important than for other organs it is, that the circulation of the brain, the tissue of which is the most delicate and sensitive, should remain unaffected by over-stimulation of the heart's action, which, in reality and effect, is the controlling power of the system, and may be likened to an engine, by means of which is kept in operation the force requisite to move the machinery of all other portions of the system, and maintain them in harmonious activity.

But, let us study this physiological effect of alcohol a little further, that we may more fully understand how much is signified by it.

Every heart-beat causes a certain amount of blood to pa.s.s through the larger arteries to the brain, and thence through its minute vessels or capillaries. It is by means of the capillary circulation that the brain, its cells, connective tissues, and all membranes, are supplied with the requisite material for life and activity. So important is the _regularity_ of this supply to the brain in the discharge of its functions, that a special arrangement of blood-vessels is provided, or rather the number of arteries is larger and their distribution more complicated and various than for any other organ. If now this supply of blood is increased by one fourth or one sixth, or in any other degree, through the action of the heart, there must result a relative increase of it to the brain-cells and tissues, together with a corresponding increase of function.

The anatomy of the brain teaches us that every fibre, brain-cell, and even nucleus, is enclosed with an exceedingly thin covering, through which its contents may be nourished, and also through which, when its const.i.tuents are no longer of any use, they may be eliminated and removed from the body. These coverings, or membranes, as they are called, in turn, derive their materials for growth and function from the minute capillary blood-vessels which, in almost infinite number, supply them, while all portions of brain tissue are together dependent upon the _regularity_ of the heart's supply of blood to enable them to discharge their functions in a normal manner.

Now, physiological experiments have shown that the effect of alcohol upon that portion of the nervous system--the vaso-motor--which presides over and supplies power of action to these capillaries, and also regulates the action of the heart, is that of a narcotic. Its effect is to partially paralyze this nerve, and leave the heart to act more freely and rapidly under the influence of the motor nerve; in consequence of this partial paralysis of the coats of the capillary vessels, when the blood pa.s.ses through them so much more rapidly than when in their normal state, they fail to absorb from the blood the material requisite to nourish them, and also fail to remove material which has already been used.

One of the most important of their functions however, is the removal of this used-up material of the brain-cell, connective tissues, and fibres.

If this is imperfectly performed, and some portion of this secondary metamorphosis of material is left unremoved, there must result at least two not very remote effects.

1. A less sensitive and delicate condition of these several const.i.tuent portions of brain-substance, and they will become correspondingly less responsive to both objective and subjective impressions or influences.

There must result, therefore, a less perfect discharge of thought-function in its various manifestations, both moral and intellectual.

2. This imperfect removal of material which has once discharged its function, and is consequently useless, will ultimately cause a thickening of the coverings of these cells and fibres of the brain, which, in process of time, must render the discharge of their function more difficult and imperfect.