Having now taken a general view of the objects, nature, and laws of digestion, and of the structure and mode of action of the various organs concerned in its performance, and made ourselves acquainted with the principles on which our conduct ought to be regulated, so as to second the intentions of Nature for our welfare and happiness, I have only to add a few practical remarks on the proper management of the bowels, and then conclude.

The proper uses of the intestines are, as we have seen, to serve, 1st, for the performance of chylification; 2dly, for the absorption of the nutritive chyle; and, 3dly, as a reservoir for the indigestible residue of the food, and an outlet for both it and the effete matter which requires to be thrown out of the general system. The processes of chylification and absorption having been treated of in a former chapter, it is in the last capacity only we have now to consider the intestinal canal.

Besides the bowels, there are several other channels by which the waste materials of the body pass out. The most important of these are the skin, the lungs, and the kidneys; and in certain circumstances, where the action of the one is impaired or repressed, the natural alliance subsisting among their respective functions, enables the rest to come to its assistance, and even for a time to supply its place. Thus, when, by continued exposure to cold, the exhalation from the skin is much diminished, the blood is thrown in upon the internal organs in larger quantity, and, as a consequence, the urinary secretion and the exhalation from the lungs are both increased, and full relief to the system is temporarily obtained. During hot weather, on the other hand, when the skin is in high action, and perspiration flowing freely, the urinary secretion is greatly lessened. The same principle applies equally to the case of the bowels; and hence the sudden application of cold to the surface of the body, and consequent suppression of perspiration, often increase the intestinal secretions to such an amount as to induce bowel-complaint. On the other hand, the excited action of the bowels by laxatives, tends equally to diminish the activity of the skin; and hence, indeed, one source of the cooling effect of saline purgatives administered in fever and inflammations.

The bowels being thus the outlet of the indigestible portion of the food, and of waste matter from the system, it follows that, in health, their action ought to bear a relation to the kind of aliment used, and to the state of the other excretory functions; and consequently, that what may constitute healthy action at one time, and in one individual, may be very far from presenting the same character at another time, and in a different individual. If, for example, a person be fed chiefly on milk, rice, or farinaceous aliment, which is almost entirely appropriated to the purposes of nutrition, and leaves very little residue, the bowels, having little to throw out, will naturally act seldomer and less fully than when the diet consists chiefly of bulky and innutritious vegetables, which leave a large portion of indigestible matter to be evacuated. Most persons are aware of the difference of effect between the two kinds of diet, but, from not being acquainted with the principle on which it depends, are apt to conclude that, because in the first case the bowels act less, therefore they ought to be assisted by laxatives. The inference, however, is by no means necessarily sound; because the diminished intestinal action consequent on an exclusively farinaceous diet is then the natural and healthy result; and accordingly, where such diet is required, the mere costiveness is attended with no injury to the constitution. The proper conclusion to be drawn from it is, that the permanent and exclusive use of concentrated food is not in harmony with the structure and functions of our digestive and assimilating organs, and that, therefore, instead of continuing their use, and merely resorting to purgatives to excite an action for the removal of a residue which does not exist, reason requires that we should select a diet better adapted to the constitution and laws of the organization by which it is to be acted upon.

The same remark applies to those who are accustomed to dine chiefly on animal food, and rice or bread, without any sufficient admixture of herbaceous or other innutritious substances. If, in such circumstances, the aliment is almost entirely converted into nourishment and absorbed, it follows, as a matter of necessity, that little will remain to be thrown out of the body, and that the bowels will act less than with a different kind of diet. If the state of the constitution at the time be such as to require the exclusive use of this kind of aliment, forced action of the bowels by purgatives will not be needed, because their slowness will be natural and healthy. But if it be not, then the proper remedy is, not to excite the bowels by irritating purgatives, but to remove the cause of the intestinal inactivity by changing the system of diet.

It may be answered to this, that there are many instances in which the stomach is unable to digest any vegetable or innutritious food, and in which, consequently, the diet cannot be altered without injury. I admit that, in the present state of society, cases of this kind are common; but their number would be greatly reduced if a proper mode of life were systematically adopted, and that regard paid to the conditions of health which their intrinsic importance deserves. There are very few individuals who, when in health, and with the aid of a proper regimen, cannot digest aliment suited to the natural constitution of the stomach and bowels; and when such cases do occur, they constitute exceptions to the general rule, and must, of course, be treated either by the use of laxatives, or such other remedies as the circumstances may require.

As the frequency and amount of the intestinal evacuations may thus vary according to the nature of the diet, without necessarily involving any disturbance of health, so may they also vary according to the state of the other excretions; and hence, again, is evident the absurdity of considering the same standard as applicable alike to all persons, times, and circumstances. If, from continued exertion, perspiration is kept unusually active, the excretion from the bowels may be proportionally diminished, not only without injury, but even with advantage to the health; because, if the same waste were to go on by the bowels as before, and the increased exhalation from the skin also to continue, the system would speedily become reduced. In consumption, for example, exhausting bowel-complaint and profuse perspiration are frequently observed to alternate, and whatever remedy is given to check the one generally aggravates the other. But if both were to run their course together, instead of singly, how much more rapidly would the system be undermined!

From this relation between the different excretory functions, it follows, that when sluggishness of the bowels is induced by excess in another excretion, the first step ought to be to remove or diminish the unnatural stimulus which has occasioned that excess, before attempting, by means of purgatives, to force the bowels to act. If the cause which has produced the deviation from the due proportion of the excretion be left unabated, the only effect of strong laxatives will be, not to relieve, but to irritate and weaken.

The mere fact of the bowels not being emptied so frequently as usual, is therefore, when taken by itself, no evidence that they ought to be stimulated by medicine. Before coming to this conclusion, we ought to determine clearly whether the diminished action results from morbid sluggishness of the intestinal canal, or is the natural result of an accidental change of diet, or temporary excess in the other excretions; because the remedy which is appropriate and efficacious in the one case, may be altogether inapplicable to the other. Where it arises entirely from the aliment leaving little residual matter to be thrown out, the health may suffer from the diet being inappropriate, but it will not suffer merely from the diminished action of the bowels. Whereas, when the diet is of the ordinary mixed kind, and the costiveness proceeds from morbid inaction, then general derangement of the system will be induced, unless the bowels be attended to, and their natural action restored. This distinction ought never to be lost sight of.

Judging from the prevalent notions on the subject, from the universal reference of all kinds of bad health to derangement of the stomach and bowels as their source, and from the scarcely less universal use of purgatives as remedial agents, one would be apt to suppose that, to ensure health and long life, nothing more was required than to procure, no matter by what means, an intestinal evacuation regularly every day; and the inference would, to a certain extent, be confirmed by the acknowledged extensive utility of laxative medicines. The real state of the case, however, is not quite so simple; and as it is of importance that it should be understood, I shall attempt to explain it as clearly as I can.

We have seen that inactivity of the intestinal canal may arise from the use of too concentrated aliment, and from excess in the other excretions. In the great majority of cases, however, the cause is very different. In general, the diet is sufficiently varied and abundant, and the balance of functions sufficiently equal to leave a considerable quantity of alimentary residue and effete matter to be thrown out by the bowels; and if it is not regularly expelled, some obstacle of a different kind must exist, which, in the first place, ought to be removed, before we can expect to succeed in restoring the natural action. To learn what that obstacle is, let us turn our attention for a moment to the natural means by which the intestinal evacuations are effected.

The progress of the intestinal contents along their canal depends, first, on their affording the necessary stimulus to excite the contraction of the muscular coat; secondly, on the assistance derived from the free action of the abdominal and respiratory muscles, not only during respiration, but during every kind of bodily exercise; and, thirdly, on the inner surface of the intestine being duly lubricated with the mucous secretion. If any or all of these conditions be unfulfilled, the inevitable result will be morbid sluggishness of the intestinal action, and the various consequences dependent on it; and hence, when the evil exists, the first point to be determined is the nature of the cause by which it is produced.

As already remarked, farinaceous and other concentrated aliments do not afford the requisite stimulus to the muscular fibres of the intestine; because they are in a great measure absorbed, and leave little to be thrown out. If, therefore, concentrated food be the cause of costiveness, the proper remedy is to alter the diet, and to have recourse to other means only where that proves insufficient. If, again, the inactivity of the bowels proceeds from the food not being sufficiently digested, and from their contents being on this account inadequate to excite them to healthy and regular action, it follows as a necessary consequence, that before we can expect to obtain intestinal regularity, digestion must be improved by steady perseverance in a proper regimen, and such other means as may be required to restore the tone of the stomach. It is in cases of this description that the practitioner is most frequently consulted. If he and the patient are satisfied with simply procuring relief, he has ready means at hand in any of the ordinary purgatives. But if a cure is their object, they must go back to the root of the evil, and begin by restoring the digestive organs to health as the first step towards permanent success.

The observance of a proper adaptation between the quantity of the food and the state of the digestive organs and mode of life, is then not less essential to the proper action of the bowels than to that of the stomach. If we eat more than the system requires, the bowels become oppressed and weakened by their load; and it is in such circumstances that purgatives afford immediate relief by the removal of the superfluity, and, by blinding the individual to the real nature of the evil, tempt him to recur too frequently to the use of medicine.

Where, however, as most frequently happens, the constipation arises chiefly from the absence of all assistance from the abdominal and respiratory muscles, and in part only from an inappropriate diet, the first step to be taken is again to solicit the aid of the former—first, by removing all impediments to free respiration, such as stays, waistbands, and belts; and, secondly, by resorting to such active exercises as shall call the muscles into full and regular action: and the next is to proportion the quantity of food to the wants of the system, and to the condition of the digestive organs. If we employ these means systematically and perseveringly, we shall rarely fail in at last restoring the healthy action of the bowels with little aid from medicine. But if we set these natural conditions at defiance, we may go on for years, adding pill to pill and dose to dose, without ever attaining the end at which we aim.

How, indeed, can it be otherwise? If the Creator has so constituted us that the free play of the lungs and muscles is indispensable to proper intestinal action, it is in vain for us to struggle against the arrangement, and expect to substitute beneficially the stimulus of purgatives for that of the natural play of the muscles. Either we must give up our own obstinate adherence to sedentary pursuits and conform to the divine laws, or we must submit to the punishment inseparable from disobedience, and merely endeavour to mitigate its severity by such partial remedies as lie within our reach.

Where bodily weakness, or any other cause, absolutely prevents us from engaging in active bodily exertion, corresponding moderation in eating, and continued kneading and rubbing over the region of the bowels, when used daily and persevered in till the strength is restored, are of great service in promoting their healthy action. Where great sluggishness of the bowels exists, and no exercise can be taken, the rubbing generally requires to be continued for an hour or more daily, or even twice a-day.

Sometimes intestinal inaction proceeds from defective mucous secretion on the surface of the internal coat, caused either by errors in diet or by local irritation. When costiveness is excited in this way, a mild diluent regimen will generally remove it. It is in such cases that saline medicines, which act by increasing the mucous secretions, are often very useful; while aloetic and other stimulant purgatives increase the evil by aggravating the irritation.

Such being the mode of action of the bowels, and such the natural agents by which it is carried on, we can now appreciate the folly of seeking to apply the same remedy to every kind of costiveness, no matter from what cause it proceeds. If a clerk who sits motionless all day in an office, who indulges his appetite, and has no bodily exercise to facilitate respiration and give a natural impetus to the bowels, begins after a time to complain of constipation, it is not difficult to tell what is required for his cure. The first step which a knowledge of the animal functions would suggest, is to diminish the food to such a quantity as the stomach can digest; the next, to use such a diet as is calculated to excite the muscular coat of the intestine to healthy activity; the third, to seek the natural aid arising from exercise of the abdominal and respiratory muscles; and the last of all, to have recourse, when necessary, to such medicines as may be required for a time to restore the tone of the bowels, and enable them to act without further assistance. The course usually adopted, however, is widely different from that here described. From ignorance of the laws of organization, the patient is not aware of the extent to which he infringes them in his conduct, and consequently rests satisfied with lamenting his hard fate in possessing such a bad constitution, and resorting to strong medicines to force that action which he feels to be essential to health, but which he will not consent to elicit by the means with which Nature has furnished him.

Among the middle and higher classes, very many females act on the same erroneous plan, and with equally unfortunate results. In them the evil is aggravated by the tightness of their clothing impeding almost entirely the descent of the diaphragm, and the free play of the abdominal muscles, in respiration.

From this view of the nature and causes of costiveness, it will be evident, that, as a general rule, the bowels are perfectly competent to the discharge of their functions, when the conditions essential for their healthy action are duly fulfilled. And hence, whenever they become morbidly inactive, we may rest assured that, in some point or other, our own management is or has been defective; and the surest way to remedy the evil is, not to have instant recourse to medicine, but to begin by discovering and amending the defect. In the rare occurrence of constipation among children and other actively employed persons, we have ample proof of the fundamental principle that the bowels do not naturally stand in need of the stimulus of medicine, but require only to be properly treated to fit them for the office with which they are charged.

While, then, I entirely agree with public opinion in attaching great importance to the proper regulation of the bowels, and in tracing much suffering to their neglect, I am only the more anxious that we should, as far as possible, follow Nature in our arrangements, and reap the benefit of her aid. If we do so, we shall not only be less frequently obliged to have recourse to medicine, but, by our knowledge of the causes of the deficient action, be greatly assisted in our selection of an appropriate kind of laxative, and thus avoid forcing the constitution too far. It sometimes happens, for example, that, from debility of the muscular coat, the peristaltic motion is insufficient to propel the contents of the intestines, even with the aid of proper diet and exercise. In such cases, small doses of aloes or rhubarb, or other laxatives, which act chiefly by exciting the muscular contraction, will be sufficient to clear the bowels, especially when any mild tonic is conjoined with them; while saline laxatives which act chiefly on the mucous coat, may be given freely, and even cause numerous watery evacuations, and yet the real or solid contents of the intestines continue unremoved. In practice this often happens; and hence the frequent mistake of supposing that there is proper passage from the bowels, when in reality there is no such thing.

The period of life at which intestinal inactivity is attended with the most serious consequences, is at and for a few years after puberty. At that age a sudden change is often made from the restless activity of youth to all the stillness of a sedentary profession, without any corresponding alteration being made in the quantity of food consumed. The vigorous appetite, which is perfectly natural during a period of growth and great bodily activity, remains at first unimpaired, and impels the individual to eat an amount of food far beyond the present necessities of the system or the powers of digestion. The consequence is a tendency, not only to fulness from excessive nutrition, but to severe digestive disorder from the stomach and intestines being weakened both by want of exercise and by excess of food. I have known many instances of dyspepsia, constipation, and mental affection, and even of active inflammation, thus produced. In one case, four years of continued bad health in an otherwise sound constitution were the penalty inflicted before the real cause was accidentally discovered. During all that time, too, temporary relief invariably followed the use of purgatives, and seemed in some measure to point to the truth; but from the mind never having been directed to the principles, its practical bearing was overlooked, and now the individual wonders that the cause did not, even at first sight, arrest the attention of his medical advisers.

In cases of this description, however, it ought to be observed, it is not the mere constipation which injures the health and requires to be removed. It is in reality to the mode of life which induces it that we ought to direct our attention; for, unless that be amended, all our efforts to preserve the health by merely removing the effect will prove insufficient.

In the natural and healthy state, under a proper system of diet, and with sufficient exercise, the bowels are relieved regularly once every day. In some constitutions, however, the ordinary period is shorter or longer than this—twice a-day, or only once in two days; but such differences are unimportant when they do not proceed from morbid causes, or in any way disturb the health. Habit, in this as in other operations under the influence of the nervous system, is powerful in modifying the result, and in sustaining healthy action when once fairly established. Hence the obvious advantage of observing as much regularity in relieving the system as in taking our meals, and the impropriety of attempting to break through the habit when once formed. Sleep seems to be favourable to the progress of nutrition, and it is apparently during the night that the assimilation of the daily food is completed, and its residue prepared for being expelled along with the other excretions. Hence there is a natural tendency in the bowels to act in the morning, and we ought therefore to encourage it by a voluntary effort. Even the reception of breakfast into the stomach seems to act as a stimulus to intestinal contraction, and in consequence many persons experience the inclination immediately after their morning repast, and suffer if they are prevented from yielding to it.

Where, either from constitutional weakness, sedentary occupation, or other unavoidable causes, the bowels are unable to act sufficiently to relieve the system without assistance, we have, of course, no choice but to select that which is most suitable to the circumstances and most gentle in its operation; because, if assistance be not afforded, the health will assuredly suffer. Numerous examples of this kind are met with every day; and, when treating them, we should always be careful to aid Nature as far as possible by an appropriate diet and regimen, and not trust to medicine alone for rectifying the consequences of the patient’s misconduct. We ought, in short, never to lose sight of the great truth, that, if the bowels were originally constituted by the Creator with power to act sufficiently on the application of their own stimulus, food, there must necessarily be a wide departure from His laws in some part of our conduct to cause the loss of that power; and therefore, whenever we find the bowels unable to act without medicine, our first business ought to be to discover and rectify the error into which we have fallen,—and recourse should be had to medicine only in so far as it shall be necessary to remedy the consequences which the transgression has brought upon us.

As the sole object of the present volume is to make the reader acquainted with the natural laws of the animal economy, and with the means by which aberrations from them may be prevented and health preserved, I shall not enter at all upon the discussion either of the morbid conditions of the bowels, or of the remedies by which these may be cured—and consequently shall say nothing farther of the use of purgative or other medicines. The consideration of these matters is not only foreign to the subject, but would require an extent of detail much beyond my present limits.

Perhaps some persons may think, that, before concluding, I ought to apologize for having introduced to the notice of the general reader such topics as those discussed in this and some of the former chapters. In doing so, I have been actuated by a deep sense of the misery arising from the prevailing ignorance on topics which, although in themselves as interesting and important as any to which the human mind can be directed, have nevertheless been passed over in silence, partly from not the least suspicion being generally entertained of their real bearing on our health and happiness, and partly also from false notions of delicacy diverting attention from their calm and deliberate examination. In endeavouring, therefore, to unfold what I conceive to be useful truths, in the language of reason, I confess that I feel no apprehension that any well-constituted mind will receive contamination from the perusal of what is contained in these pages.