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EVERY MAN'S MASTER.

(Concluded from p. 358.)

BEFORE we enter into any explanation as to the relative proportion of nourishment contained in the various substances which nature has provided for our use and sustenance, it will be proper, first of all, to offer a few observations on the mode in which the food in general is assimilated to the blood; and of the powers with which the stomach has been gifted for this important purpose. We have already briefly touched upon this subject; but our observations were confined merely to the effect of liquid stimulus upon the stomach: we shall now, therefore, enter more fully into the explanation of digestion.

“ The process of digestion,” to use the words of an acute modern writer*, may be defined—the conversion of dead into living matter; at all events, it is the conversion of dead animal and vegetable substances into an animalized fluid, qualified to enter into the current of the circulation, and then to become part and parcel of the living machine. No other fluid, not even milk from the living udder, can be poured into the blood vessels without risk of life; and, therefore, we are authorized to conclude, that the chyle (that is, the digested food) is a vitalized fluid like the blood itself. If this be a correct representation, all inquiry as to how the change is effected will be just as successful as the inquiry how man was changed from a lifeless clog into a living animal, at his first creation. But the prying eye of the physiologist has penetrated into some of nature's secret operations, and there are several very curious and interesting phenomena attendant upon the process of digestion."

We have already stated that digestion is a compound process, in which the gastric juice is the principal agent; and, as far as the action of the human stomach is concerned, all that we have to do, is to ascertain—not only the precise nature of the operation of this remarkable solvent, but those substances upon which it will act most freely and effectually: for in this consists all the good result that is to be deduced from a knowledge of the modus operandi of the process. Many experiments have been instituted to arrive at this consummation, Reaumur inclosed alimentary matter in tubes which were pervious at both ends, and introduced them into the stomach of animals; when they were discharged, he found that the ingredients were so acted upon by the gastric juice, as to be almost dissolved. The following interesting experiments, related by Dr. Stevens, in his work De Alimentorum concoctione, will show, in a very striking manner, the powerful solvent effect of this stomachic menstruum. The first was tried upon a man who had a strange propensity for swallowing stones. Alimentary matter was introduced into hollow silver spheres, divided into two. cavities by a partition, each being perforated with a number of aper

* Dr. James Johnson, whose work on the Morbid Sensibility of the Stomach and Bowels, is one of the best, and least pretending books, that have been written on that interminable subject. MAY, 1829.

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tures, to allow of the free ingress of the gastric juice. In one experiment, a portion of meat was put into the one of the cavities, and in the other some fish: when the sphere was discharged, both the substances were found to have been digested,—but more especially the fish. In another experiment, the doctor, wishing to ascertain how far the cooking of meat interfered with its digestion, introduced a quantity of boiled meat into one part of the sphere, and some roast into the other ; by which he discovered that boiled meat is more digestible than roast. The next discovery which he was anxious to effect, was the comparative influence of this extraordinary solvent upon food previously masticated, and upon that which was swallowed, without this preliminary preparation. This experiment was conducted like the others; and, as might have been expected, the food which was previously masticated, was more perfectly digested than the other.

Finding that animal substances thus submitted to the action of the gastric juice were easily digested, Dr. Stevens made many experiments on vegetables, which were not digested so easily as animal matter. This led the doctor to ponder upon the properties of inanimate matter generally, in reference to the process of digestion; and to institute experiments to ascertain how far the gastric juice would act upon actually living matter. To discover this, he enclosed a leech in a sphere, to prevent its wounding the stomach. The man swallowed it, and, when voided, nothing was found in the sphere, but a viscid black miasma,—the undefined pulpy remains of the digested leech.

A word or two on this experiment. It is a uniform rule in the animal economy, that living matter is not subject to the influence of the gastric juice. There is in vitality a certain repellent and powerful principle, which effectually obviates the action of this solvent; and worms and animalculæ have been known to exist in the stomach uninjured by its secretions. The leech, then, which Dr. Stevens introduced into the stomach, must have been deprived of vitality before the gastric juice could have dissolved it. We shall be told of the occasional digestion of the stomach itself-a fact, certainly indisputable; but the stomach is never digested until its vitality is impaired. This very curious fact never occurs excepting in cases of sudden violent dissolution ; and must depend upon the quick abstraction of nervous energy,--and, consequently, of the capability of resisting the effects of dissolution, -and the powerful action of the gastric juice upon the part thus deprived of the power of resistance.

Dr. Stevens, having no longer an opportunity of conducting his experiments on the man, had recourse to dogs and ruminating animals. Having previously weighed a quantity of animal and vegetable matter, he enclosed them in different ivory spheres, and made a dog swallow them. Some hours after this the dog was killed, and the animal food was found to be by far the most dissolved. The gastric juice of these animals has such a strong solvent power, that the ivory spheres which were employed were found to have been acted upon. He then made several experiments on herbivorous animals, by giving them animal and vegetable substances, enclosed in different tubes. When these were discharged, the animal food had undergone no alteration; while, on the contrary, there were no remains of the vegetable matter.

These experiments are very important as explanatory of the peculiar and extraordinary qualities of the gastric juice; they are useful, also, as affording an accurate guide to a perfect and proper knowledge of that “ mysterious business” digestion, and of the means by which this process assimilates the food to the living frame. We cannot always account for the mysterious and beautiful operations of nature by analogical reasoning; and nothing but experiments-well contrived, and carefully performed, can reveal to us the wonderful secrets by which her laws are regulated.

Man is an omnivorous feeder*, and imbibes nourishment in abundance from both the animal and vegetable kingdoms. Indeed, if we scrutinize the matter closely, we shall find, that all animal matter is originally formed of vegetable. “ Remember,” says one of our dieteticians, " that an ounce of beef contains the essence of many pounds of hay, turnips, and other vegetables ;” and those animals only, with one or two exceptions, are admitted to our table, that subsist entirely upon vegetable matter. It should seem, indeed, that meat- as far as mere nourishment is concerned-is used more from habit and luxury than actual necessity; for it is a well-established fact, that farinaceous vegetables, which contain sugar and oil in large quantities, are more than sufficient for the purposes of nutrition. In proof of this, we need only adduce the mode in which the peasantry in the remote parts of this kingdom ordinarily subsist. In Wales, in Ireland, and Scotland, in the North, and, indeed, in all secluded districts, the poor seldom taste meat: oatmeal, potatoes, ryebread, and milk, constitute their usual, almost their only, food. And where can we find a more robust, athletic, healthy race of ment? In France, and on the continent generally, meat is by no means so grossly gormandized as it is in many other countries. Potage, bouilli, etuvées, hachis, vol au vents, sautés, and salmis, in the composition of most of which sundry vegetables form, by far, the greatest proportion,with light wines, constitute the national diet of many of our continental neighbours; and, rigidly eschewing the heavy and substantial edibles, which delight the stomach of Monsieur l'Anglais, they retain their vivacity and sprightliness under every mutable vicissitude of human existence.

But habit is not to be despised ; and we should consider ourselves sadly treated, were we deprived of the noble sirloin and of the luscious haunch. Such being our propensities, it becomes necessary to submit a few general remarks on the qualities of the different articles of ani. mal food.

As a general rule, no meat comes to perfection under a stated period of growth. Beef and mutton“ five years old,” are infinitely better than veal or lamb, or young pork, - better, as containing more nutriment, as well as being more easily digested. Fish contains,

* It is worthy of remark, that in this instance man is closely imitated by the pig, and hy no other animal. His swinish rival resembles him, also, in another particular, that, namely, of enduring the extremes of temperature “ from Indus to the Pole."

+ The classical reader will scarcely need to be reminded that figs, “ a very sac. charine fruit,” were the chief food of the ancient Athletæ.

comparatively, but little nourishment; and well might Lord Byron have exclaimed—“A Lent will well nigh starve ye!”—for Haller, the first of European physiologists, alleges, that persons are generally weakened by a Lent diet; and Pechlin corroborates his assertion without any reservation. It is very certain, however, that some fishes possess a larger share of nutritive properties than others, and these are the fat or oily kinds, as salmon, eels, and herrings.

“ With regard to the last,” observes Cullen, in his Materia Medica,“I may observe, that our herring-fishers, living for some length of time upon this aliment alone, suffer no loss of strength, but seem rather always to be much fattened by this diet.” Fish, however, used exclusively, is neither a wholesome nor a nutritious food : witness the effect of salmon upon the Scotch and the Welsh, when that fish existed in such profusion as to render necessary a specific agreement, on the part of servants and labourers, that they should not be surfeited with it. Oysters, too, have been extolled as a remède universel, without any justifiable reason. The nutritive properties of this fish are by no means extensive ; they merely fill up a niche in an empty stomach, and stay its cravings till food more substantial and more salutary can be obtained.

We must say a word or two upon birds, which, next to butchers' meat, are the best articles of diet. It is rather curious that there should be so much difference between the white and brown meat of birds. There is a greater degree of stimulus and strength (to speak popularly) in the latter than in the former ; which has been thus accounted for by the chemists-and, by the way, the explanation will apply to the meats of all animals. The difference, say they, depends upon the greater number of arteries, and, therefore, upon the greater number of red globules of blood, interposed between the muscular fibres. As it is probable that these red globules are considerably alkalescent, -that is, impregnated with alkali-an article very favourable to digestion,-it will follow that the brown or red flesh is more alkalescent than the white, more easy of digestion, and more nourishing. The brown kinds of game are, consequently, more beneficial than poultry; and ducks and geese*, in addition to their savoury qualifications, are gifted with divers other more durable and valuable virtues. But, in accordance with the rule already laid down, the young of birds, as well as those of the mammalia, are not so nutritious as the animals who have attained their full growth; and while we all know that an old cock pheasant, or partridge, is a vapid and most tough morsel, we should bear in mind, that a

“ first year's bird” cannot have attained its full flavour. We may here give our epicurean friends a gentle hint. In eating game, those parts are the most tender and delicious which are exercised the least by the locomotive habits of the bird. For instance, in the woodcock and snipe, the legs, which are merely used as their supporters, are juicy and

* Dr. Stark, in his Experiments on Diet, has entered very deeply into the consideration of this important subject ; constituting himself the object of his own experiments. He has established, beyond all dispute, that roasted goose contributes, more than any thing else, not only to the vigour of the body, but to the activity of the mind !

tender; while the wings and breast (pectoral muscles), being abundantly exercised, are more tough, dry, and strong.

It is not our intention to enter more deeply into the consideration of these different articles of diet ; nor shall we perplex our readers with a formal and formidable analysis of their several properties. We have told them what is good, and pointed out what is bad; and we have endeavoured to arrange our remarks as lucidly as possible. Were we to proceed further instead of writing an article, we should speedily concoct a volume : but our object has been to furnish a succinct and complete condensation of all the information which we have found scattered throngh many volumes-to winnow the light chaff from the solid grain, and to present the reader with a sketch of “ English and French dietetics," plain, palpable, and instructive. One cautiou we would again enforce—and that is, Temperance. “ Nunquam satiari cibis et impigrum esse ad labores”-is a good, sound, and sensible maxim; and we verily believe that it matters very little what the quality of the food may be which we eat, provided we take all proper precaution as to the quantity. There can be no wisdom in putting into the stomach more food than it is capable of digesting; and Mr. Abernethy has promulgated a golden rule, for which the public and posterity ought to feel much indebted to him. “ We should,” he says, “proportion the quantity of food to the powers of the stomach, adapt its quality to the feelings of the organ, and take it at regular intervals of six or seven hours during the day.”—This is the whole mystery of diet,--and how simple and easy of comprehension it is !

FAMILY PORTRAITS.

No. VI.—THE SECOND BEST.

“ I wonder,” Mr. St. John said, one day, to me, “ that you have not yet put any question to me concerning a picture towards the extremity of the gallery, to the right."

“ I know which you mean," I answered, interrupting him,—" it is that of a lady no longer young-but whose mild, kivd, sensible countenance amply repays the absence of youth, and of strictly regular beauty. Yet of this last there is a substitute that may almost be considered superior to that which it supplies, namely, the expression of a mind and heart equally noble; the former strong, clear, and cultivated, and the latter running over with the milk of human kindness."

“ Ah?"-exclaimed St. John, with a long aspiration,—“I am now still more surprised that you never spoke on the subject of this admirable woman; for you certainly are more closely right in your primary guesses of her character, than in those of any we have yet discussed.”

My reason is, that I have not been able to make out any outline, even, of her story-and I wanted to find something that seemed to me

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