Eggs

For the same reason the white of eggs, which consists wholly of albumen, is a most excellent medium of nutriment where, for any reason, beef-tea cannot be given. The white of egg stirred into cold or lukewarm milk can often be given to children or other patients who refuse beef-tea. It is tasteless and colourless, therefore its presence can be disguised; whereas the yolk of egg contains fatty matters with albumen, and is easily recognised by the child both from its colour and its flavour.

Water, either as an ordinary article of diet or a means of allaying the thirst in febrile states, requires that great care shall be taken to ensure that it shall be free from impurities.

The most dangerous impurities to which water is obnoxious are gaseous matters, and insoluble animal and vegetable matters.

Gaseous matters and vapours are readily absorbed by water, as is seen in the ordinary experience of placing a basin or tub of water in a newly-painted room, whereby the smell of the paint is quickly removed. Water, by reason of the same property, should never be drunk from a cistern into which there is a waste-pipe having a direct communication with a drain or reservoir. The poisonous gases arising from the decomposing sewage are absorbed by the water, which thus becomes the vehicle for the conveyance of the poison of malignant fevers.

The decomposing animal and saline matters of sewage also readily percolate a porous soil; so that if a well and a cesspool be near one another, as is often the case both in town and country, the water becomes the channel through which deadly poison is carried.

Rain water received into leaden cisterns, or water in tanks having leaden pipes leading from them, is often contaminated by a portion of that metal becoming oxidized and dissolved, producing colic and other signs of lead-poisoning.

For ordinary domestic purposes water is classed as hard or soft. The latter is rain water; the former spring or river water. These vary much in their degree of hardness, as may readily be noticed by their behaviour with soap. With hard water the soap does not readily make a lather, but curdles on the hand. The source of hardness of water is in the lime and other salts that are dissolved out of the strata of the earth through which it has passed. These may be separated to a considerable extent by boiling, or by the addition of small quantities of bicarbonate of soda. This is the object of some persons who put a small portion of bicarbonate of soda into the teapot when making tea.

Insoluble impurities can be separated by Lipscomb's filters, or by any arrangement by which it is made to pass through fine sand or broken charcoal. The charcoal has the property of absorbing gases from water and rendering it sweet and' pure.

Pure water may be obtained by distillation from sea-water, but it is always a difficult process, and requires an elaborate apparatus. Nearly every large ship has now, we believe, a still for this purpose fitted up before going a long voyage.

In the treatment of disease, water is of primary importance, as it allays thirst and fever by diluting the blood and giving the medium by which a poison may be eliminated from the system. In fever and in cholera thirst is often the one great complaint, and the cry is for water ! water ! This indication of nature may safely be followed, and the patient allowed to drink as freely as he will.

Water is the chief of diuretics; it increases the secretion of urine, and promotes thereby the evacuation of effete or irritant matters from the blood.