"THERE is a wisdom in this beyond the rules of physic: a man's own observation, what he finds good of and what he finds hurt of, is the best physic to preserve health. **** If you make physic too familiar, it will make no extraordinary effect when sickness cometh. I commend rather some diet for certain seasons, than frequent use of physic, except it be grown into a custom; for those diets alter the body more, and trouble it less."-BACON.

MANAGEMENT

OF

THE ORGANS OF DIGESTION,

IN HEALTH AND IN DISEASE.

CHAPTER I.

MANAGEMENT OF THE STOMACH.

In the first chapter of the volume, to which the present is intended to form a supplement, I have endeavoured to explain the physiology of digestion, and the nature of the changes which the food undergoes in the stomach, and to lay down the principles which should regulate the quantity, quality, and frequency of our meals at different ages, and in various states of health. The following is a summary of the observations offered on those subjects, or rather an enumeration of the principal heads of the discourse on Diet in the treatise referred to.

The process of digestion is the solution of food in the stomach through the chemical action of an acid fluid, called the gastric juice, which is poured out

B

by the lining membrane of the stomach, much in the same manner as the perspiration exudes upon the surface of the skin on other occasions, and for other purposes. The quantity of gastric juice, which the stomach can furnish at a single meal, depends not only on the quantity of digested food which the system is in want of to make up for previous waste, and to supply the materials of its growth, but on a great variety of other causes, which are capable, directly or indirectly, of raising or lowering the powers of digestion. In health, the appetite is the natural index and measure of the ability of the stomach to digest.

Of what we introduce into the stomach, a greater or less quantity is water, pure, or nearly SO. Water, and such simple liquids as water containing a very small proportion of wine or ardent spirit, neither are digested, nor mixed up in the process of digestion, but are carried away from the stomach soon after they have been introduced into it, leaving any food which may have been taken at the same time, to be digested. The quantity of simple liquid (within certain limits, of course) taken at a single meal is, therefore, of little consequence, as every one knows, by experience, who has sat down to dinner thirsty from exercise. But the habitual practice of taking large quantities of liquid is, on the other hand, highly injurious; liquids fill the stomach and

bowels with wind, and lead to the production of a relaxed habit of body, causing either fat, or excessive perspirations, or both, and immoderate flow of urine. The less liquid taken daily, the firmer the flesh, the stronger the stomach, and the wholesomer the condition of the body.

Liquid combined with food as in soups and broths, taken as a meal, is commonly not easy of digestion, or the gastric juice finds a difficulty in getting at and acting upon the food in this state of mixture. But this holds in health only, and during illness the rule is often reversed.

The uses of liquid, as part of our diet in health, are, first to make up for the waste occasioned by excessive perspirations, or alvine discharges; secondly, to form vehicles, by which different stimulants and restoratives may be introduced into the system, such as tea, coffee, and the like, that contribute to our health or comfort.

That which constitutes our food, if for a single meal, must possess one quality; if for a succession of meals, it must combine three.

The food for a single meal must be digestible; for a succession of meals, digestible, nutritious, stimulant.

The essence of digestibleness is, that the gastric juice should easily penetrate and act upon the food. The food may resist the action of the gastric juice either mechanically or chemically; tough hard

meat, especially if swallowed in unchewed morsels, exemplifies the first source of indigestibleness, so likewise oily food, and broths and soups. The flesh of young animals, of pork, of duck, and other rich meats, is refractory in the second way.

Different sorts of food are nutritious in very different degrees. The flesh of adult warm-blooded quadrupeds furnishes most nutriment; next that of birds, game more than poultry: then the best farinaceous food, arrowroot, wheaten bread, &c., then fish; finally, inferior farinaceous food, and esculent and mucilaginous vegetables and fruits.

Food must have a stimulating quality. If animals are fed on any one kind of concentrated food exclusively, they fatten, indeed, for the first fortnight, but then they begin to lose flesh, waste, and, after a brief period, die. A stimulating quality is imparted to food in four ways,-first, by using aliments that are not simple and concentrated,— milk, for instance, instead of sugar, or butter alone secondly, by varying our food at different meals thirdly, by the use of condiments: fourthly, by taking with our meals fermented liquors.

In infancy and childhood, what is wanted is food easy of digestion, but not stimulating, nor of the most nutritive quality, for that in early life heats and excites. Food of this description is signified by the term "light food." Light food goes with frequent meals,—that is to say, the stomach which