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Dialysis

Is the term applied by Professor Graham to a process devised by him for separating bodies by taking advantage of their tendency to form crystals or to remain in the amorphous or glue-like condition.

It is well known that many bodies have a tendency to crystallize, such as salt, sugar and alum; others, as albumen (white of egg), glue and the like are never known to assume the crystalline form. Professor Graham has found that if a mixture of the former, which he terms crystalloids, with the latter (colloids), be placed in a vessel havoperation, if not administered with caution and ing its sides or bottom constructed of animal memjudgment. For the body, by long fasting, is reduced to a state of more than infantile debility; the minuter vessels of the brain, and of the other organs, collapse for want of food to distend them; brane or parchment paper (page 436) and floated or immersed in water, the crystalloid will pass through into the surrounding liquid, while the colloid will remain. This is not an action analogous to ordinary filtration, for the membrane is water-proof, but is of a more complex nature. the stomach and intestines shrink in their capacity; and the heart languidly vibrates, having scarcely sufficient energy to propel the scanty current of blood. Under such circumstances a pro-ment-paper; it resembles, in fact, an ordinary tamper application of heat seems an essential measure, and may be effected, by placing on each side, a healthy man in contact with the patent. Pediluvia, or fomentation of the feet, may also be used with advantage.

The temperature of these should be lower than that of the human body, and gradually increased according to the effects of their stimulus. New milk, weak broth, or water-gruel, ought to be employed, both for the one and the other; as nourishment may be conveyed into the system this way, by passages, properly the most pervious in a state of fasting, if not too long protracted.

It appears safer to advise the administration of cordials in very small doses, and, at first, considerably diluted with either wine or spirits; but slender wine whey will very well answer this purpose, and afford, at the same time, an easy and pleasant nourishment. When the stomach has been a little strengthened, an egg may be mixed with the whey, or administered under some other agreeable form.

The yolk of one was, to Cornaro, sufficient for a meal; and the narrative of that noble Venetian, in whom a fever was excited by the addition of only two ounces of food to his daily allowance, shows, that the return to a full diet should be conducted with great caution, and by very slow gradations.

Welsh Rabbit.

Cut your cheese into small slips, if soft; if hard, grate it down. Have ready a spirit-of-wine lamp, etc., and deep block-tin dish; put in the cheese with a lump of butter, and set it over the lamp.

Have ready the yolk of an egg whipped, with half a glass of Madeira, and as much ale or beer; stir your cheese when melted, till it is thoroughly mixed with the butter, then add gradually the egg and wine, keep stirring till it forms a smooth mass. Season with Cayenne and grated nutmeg.

To be eaten with a thin hot toast.

Impromptu Chafing Dish.

It often happens that in travelling, the materials for a rabbit may be had when there is nothing else in the house the gourmand can eat. In this case, if there is no blazer, or chafing dish, an excellent substitute is formed in a moment by two soup plates, ser arated from each other by pieces of a bottle-cork placed on the rim of the lower one, which should contain any kind of spirits.

Put your cheese into the top one, fire the spirits with a slip of paper, and set your rabbit on the The dialyzer of Professor Graham consists of a hoop of wood having its bottom made of parchbourine. This is floated on the surface of a liquid and the mixture is poured into it. After a time the liquid gives on evaporation the crystalloid, salt, for instance, while the colloid, jelly, for instance, remains within the dialyzer.

Among the results of investigation with this apparatus have been the discovery of silica (sand, rock-crystal) in a soluble form (page 434) and the separation of crystalline poisons from organic matters in the stomach after death; many others will be found in the recent scientific journals.

Utilization of Brine.

Mr. A. Whitelaw has proposed to use the process of dialysis for obtaining the large amount of nutritious matter which exists in the brine of salted meats, and which is usually thrown away. According to Mr. W., 2 galls. of brine yield 1 lb. of solid extract, which makes a palatable and nutricious soup. It is only necessary to enclose the brine in bags of animal membrane, and immerse them in water; the salt passes through, and the albuminous and extractive matters remain.

To Freshen Salt Meat.

Another application of dialysis is that of rendering salt meat more juicy, tender and digestible. The meat is placed in a bag of untanned skin, which is nearly filled with brine from the beef-barrel. This is placed in sea-water for several days, when the brine, having lost its salt by dialysis, becomes reduced in strength to that of sea-water. The beef, which had been contracted by the action of the salt, gives up its salt to the brine in the bag, swells and absorbs part of the juice which it had given out to the brine. In this way no loss is sustained by steeping, and the brine left in the bags, after a nightly dialysis, may be used for soup.

Thoroughly salted meat without bone gradually takes up nearly of its weight of juices from the brine. It becomes then somewhat like fresh meat, and may be cooked in a variety of ways which are inadmissible for salt meat.