Chlorine is a greenish-yellow gas, belonging to the halogen group of elements. The title "halogen" is derived from the Greek word meaning sea, and is so given because the most important members of the group are obtained directly or indirectly from the ocean - viz.: chlorine, obtained from sea-salt; bromine, from sea-water; and iodine, from sea-weed.

Chlorine itself is not official, but is represented in medicine by several of its compounds; also by hydrochloric acid and chlorinated lime, by which it is furnished. Chlorine is irrespirable, and of strong penetrating odor. It is soluble in water, in the proportion of two parts gas to one Dart water. If inhaled in 7 any quantity it irritates the lining of the air-passages, causes spasm of the glottis, and narcotizes the brain.

It is a most powerful disinfectant, antiseptic, and deodorant, its great activity in these respects being due to its affinity for hydrogen, by which it decomposes compounds containing hydrogen, and sets oxygen free in its most active state, as ozone. It is not used in disinfecting clothing, as it destroys the color and texture of fabrics, nor the person, as it cannot be breathed in a strength sufficient to destroy germs. For disinfecting rooms it may be prepared as follows: Mix equal parts of common salt and black oxide of manganese. To a tablespoonful of this powder, in a saucer, add a tablespoonful (℥ ss.) of strong sulphuric acid diluted one third with water. In cold weather the saucer should be heated. This will produce enough chlorine to disinfect a room thirty-two feet square.

Calx Chlorinata. Chlorinated Lime

Made by the action of chlorine on slaked lime, containing 30 per cent. chlorine. Its action as a disinfectant is that of chlorine, and when so used it should be perfectly fresh or it is valueless. To test it, dissolve a little in water; if the solution is clear it is good, but if it has lost its chlorine the solution will be turbid and milky. This preparation is popularly called chloride of lime.

Liquor Sodae Chlorinatae. Solution Of Chlorinated Soda. Labarraque's Solution

Contains sodium carbonate and chlorinated lime. A greenish-yellow liquid, with sharp salty taste and very slight odor of chlorine. It is a good preparation for cleansing purposes in sick-rooms, wards, etc., in weak solution. In full strength it removes stains from glass. Medicine droppers, douche nozzles, and other small articles which are hard to clean may be soaked in it until the stains come away.

The antidote, in case of poisoning by any of the chlorine compounds, is albumin: white of egg, milk and flour.