Diet, in animal economy, a regimen or course of living, adapted both to the preservation of health, and its recovery, especially from chronical diseases.

The dietetic treatment ought to be conformable to the different constitutions of individuals. Those whose solids are relaxed and weak, should avoid all tough or viscid food, and such as is difficult to be digested. Their nutriment, however, ought to be substantial ; and they should take frequent exercise in the open air. The plethoric, or those who abound with blood, cannot more effectually consult their health, than by a sparing use of whatever is in a high degree nourishing, as fat-meat, rich wines, strong ale, etc. Their aliment should consist chiefly of bread, or other vegetables, and their drink of water, whey, or small beer. - See Corpulency.

Persons of a lean habit ought to follow a course directly opposite to that before suggested. Those who are troubled with acidity, should live chiefly on solid meat; and those afflicted with hot alkaline eructations, should principally use acid vegetables. Invalids sub-ject to the gout, to low spirits, to hypochondriac, or hysteric disorders, should avoid all flatulent food, as also all salted, or smoke-dried provisions, and whatever is difficult of digestion, or apt to turn sour and rancid on the stomach.— Their food should be light, spare, cool, and of an opening nature.

Another important object to be considered, is the manner of life and age, together with the season and constitution. Those whose inclination, business, or profession lead them to a sedentary life, ought to be more sparing as to the quantity, and more attentive to the quality of their aliment, than others whose pursuits are widely different, or who are accustomed to take much exercise : the former ought particularly to avoid the use of every thing that is sour, flatulent, rancid, and oppressive to the digestive organs.

Persons liable to particular diseases, should be cautious in eating whatever tends to aggravate them. The gouty, for instance, should avoid drinking rich wines, strong soups, or acids. Those who are subject to the gravel, ought to shun all austere and astringent aliments: nor should the scorbutic indulge in animal food.

The aliment in early life ought to be light, nourishing, and taken frequently, but in moderation : that of adults should be solid, and sufficiently tenacious ; the diet proper for those advanced in life, should resemble that of infancy.— At every period of life, gluttony ought to be sedulously avoided; for, not unlike too great abstinence, it destroys the powers of digestion; but the moderate repetition of aliment is necessary for restoring the continual waste of the body.

Diet ought also to be regulated according to the different seasons of the year ; because variations in the atmosphere produce corresponding changes in animal bodies. In consequence of the increased elasticity of the air, in the winter, the fibres are stronger, and better qualified for performing their various functions, and for digesting the stronger kinds of food. If there be no particular reason for the contrary, generous, wines, and whole-some ale, together with warm broths and infusions, may be then taken, to promote the insensible perspiration, which is in some degree checked ; as the cold air remarkably contracts the cutaneous pores. Some attention should also be paid to this circumstance, that the perspiration bear a due proper tion to the liquid and solid nutriment consumed.

In the spring, the quantity of food ought to be somewhat diminished, and an additional allowance of the liquor usually drunk, might be granted. In autumn, similar regulations are to be observed, as in the spring} because the moisture and density of the air are nearly the same, and the weather is equally variable ; so that perspiration is easily obstructed. During the summer, health may be most effectually preserved by vegetables, and diluent liquors, Considerable care should be taken to abstain from provisions that are heavy and difficult to be digested, but especially from wine and brandy.

The feeble and convalescent ought to eat frequently, and but little at a time: the number of meals should be proportioned to the weakness of their frame : - for it is far less hurtful to a debilitated person, to eat a few mouthfuls every hour, than to make two or three hearty meals in one day : an exception, however, ought to be made with respect to those who are naturally of a delicate and irritable constitution. - See Food and Drink.

Family-Diet. After the various and successful experiments made by Count Rumford, and others, who have written on domestic economy, little novelty can be expected in this article; but as the present work might be considered as incomplete, without some information on this important sub-ject, we have selected a few practical hints which appear to merit particular attention.

Dr. Lettsom has observed— ("Hints designed to promote Bene-Jicence, Temperance, and Medical Science," 8vo. 1797), that pies are more advantageous than either roasted or boiled meat. This he illustrates by an account of a dinner, where eight persons were completely dined off a pye, consisting of 24 oz. of wheaten flour, 64 of mutton, and eaten with 81/4 oz. of bread; weighing in the whole 961/4| oz., while 60 oz. of mutton roosted, and eaten with 33 oz. of bread, weighing in the whole 93 ounces, dined only five of the same persons.

Milk pottage is far more whole-some than tea with bread and butter ; and, if made after the following manner, is in many respects preferable to milk alone : Let equal quantities of milk and water be boiled up with a little oatmeal, which will break the viscidity of the milk, and be at the same time more easily digested than the latter in an undiluted state. Besides, oatmeal is a much warmer nourishment than wheaten flour, and agrees better with weak stomachs.

Potatoes, if properly boiled, are an excellent and nutritious food. Particular care ought to be taken that they be good, and nearly all of the same size; the larger and smaller ones should, therefore, be boiled separately. They must be washed clean, without paring or scraping, and put into a pot with cold water, but not sufficient to cover them; for their own juice will supply the apparent deficiency. If the roots be of a large size, as soon as they begin to bod, some cold water should be poured in, and occasionally repeated, till they are boiled through to the centre : Otherwise they will crack and burst on the outside, while the inside will remain half raw. During the time of boiling, a little salt should be added, and the slower they are cooked, the better will be their flavour. As soon as potatoes are done, the water should be poured off, and the roots re-placed Over the fire, in order that their moisture may evaporate, and they become dry and mealy; in which state they may be served up, without being previously peeled. This method of boiling or stewing potatoes, ist in every respect superior to that of steaming; as by the former process they may be dressed in a shorter time, and will retain no moisture.

Potatoes may be made into puddings, which will both prove an agreeable change of food, and be at the same time uncommonly nu-tritions. Dr. Lettsom directs 12 oz. of potatoes, boiied, skimmed, and mashed ; one oz of suet, and an equal quantity of milk and cheese, to be mixed together with boding water to a due consistence, and baked. An ounce of red-herring may be occasionally substi-tuted for the cheese, and will give the pudding a flavour which is relished by many. - See Potatoes.

Barley-broth is an wholesome and nourishing dish ; which, as it may be made with almost every kind of garden vegetable, is never out of season. Onions, leeks, and parsley, generally constitute part of the ingredients, to which may be added cabbage, or greens, turnips, carrots, and peas. These are to be mixed with 4 quarts of water, 4 pounds of beef with the bones, 4 oz. of common barley-meal, and slewed together for two hours,; when the herbs may be added, be-ing previously cut small, and likewise a small quantity of salt. The whole should then boil till it be tender, and the fat skimmed off or not, at pleasure. Onions or leeks' should never be omitted.

There is another article of domestic economy which is usually classed under the name of Pottage for the making of which we have subjoin' d one 01 two recipes:

1. Take 3lbs. of the sticking piece of beef, a part of the shin, or any coarse piece. Boil it in eleven quarts of water for two hours: then add a pound of .Scotch barley, and boil it four hours longer, when61bs. of potatoes may be added, and half a pound of onions, together with a small proportion of thyme, pepper, and salt. With these may be mixed other vegetables, and half a pound of bacon cut into small pieces. The whole should be boiled over a slow fire, that it may acquire a proper consistence. It will yield three gallons of excellent and nutritious pottage, and has been found amply sufficient for twenty soldiers, without bread ; the nature of the food not requiring any. The expence of this was a few years ago about 2d.per head; but, at the present advanced price of provisions, would at least be double.

2. Take of beet 1 pound, potatoes 2lbs. Scotch barley, one-third lb., a similar quantity ot onions, together with a small proportion of salt, and pepper, and 3 oz. of bacon. The whole expence of these ingredients will be about 18d. Let them be well boiled in a due quantity of water, and they will afford nutri-ment sufficient to dine and sup three persons, without requiring either bread or beer.

Messes, or pottages like these, are doubtless far preferable to the common dishes, consisting of fat bacon and cabbage, with which a considerable quantity of bread and beer are always consumed. We, therefore, seriously recommend the adoption of such or similar measures of prudent frugality, to all classes of society, especially at the present period, when all the necessaries of life have, partly from real, and partly from artificial scarcity, been raised to an exorbitant price. Those benevolent minds who feel an interest in this useful inquiry, we are obliged to refer to the "Reports of the Society for increas-ing the comforts and Lettering the condition of the Poor," where they will find the subject minutely discussed, and many gross, though common, errors, in domestic economy ably exposed.