"Take of dry muriate of soda, one hundred parts; oxide of manganese, thirty parts; sulphuric acid, eighty-seven parts; and water, one hundred and twenty-four parts. Add the acid gradually to the water, and when the mixture is cold pour it on the muriate of soda and the oxide of manganese reduced to fine powder, mixed carefully, and put into a retort; then in a proper apparatus, by means of a gentle heat, moderately augmented, transmit the gas liberated from the mixture through two hundred parts of distilled water, until the effervescence ceases in the retort."

1 Pharmcologia

Chlorine water must be kept in well stopped glass vessels, in an obscure place.

Syn. Acide muriatique oxigene (F.), Vollkorame Salzsaure (G.), Orerzuures Zoutzuur (Dutch), Acido muriatico ossigenato (I.).l

In the process by which this solution is prepared, chlorine comes over in the gaseous form, and is washed in the distilled water, which is placed in a Woolfe's bottle, or a globular vessel a, connected with a retort containing the mixture that furnishes the chlorine. The gas, as it passes through the water, in part condenses and combines with it, while the un-condensed portion passes on to the other vessels b, c, d, and there combines with the water, forming this solution, which is a solution of chlorine. The safety tube e prevents any explosion from the too rapid extrication of the gas. The last receiver should contain a mixture of quicklime in water, to absorb all the superfluous gas.

Chlorine was discovered by Scheele in 1774, while making his experiments on manganese; and was termed by him dephlogisticated marine acid; but its nature was not perfectly understood until it was investigated by Sir H. Davy, who discovered that it is an elementary substance, and named it chlorine2 from its colour, which is yellowish green. Its equivalent is 35.42. Cold water absorbs twice its weight of chlorine. When moist chlorine is exposed to a temperature of 32°, yellow crystals are formed.

Qualities. - The saturated solution of chlorine, of the Dublin College, has a peculiar, suffocating odour; and a harsh, styptic, but not acid taste. Its colour is a very pale yellowish green : it destroys all the vegetable colours, rendering them white. It must be kept in opaque bottles, or in a dark place : for by the action of the solar rays, part of the water is decomposed; the hydrogen of which, uniting with the chlorine, forms hydrochloric acid, which remains in solution in the water, while the oxygen is set free. At a temperature of 50° this solution contains about twice its volume of chlorine. The aqueous solution of chlorine acts on almost all the metals, forming chlorides.

1 All these terms are now generally admitted to be erroneous, there being really no such substance as they imply: the composition alluded to is the solution of a simple elementary body, chlorine, in water.

2 From green.

Medical properties and uses. - Aqueous solution of chlorine is stimulant and antiseptic. It has been strongly recommended in scarlatina and malignant sore throat; and as an antisyphi-litic remedy. In the latter disease the same opinion may be given of it as of the simple hydrochloric acid; but in scarlatina and cynanche maligna more benefit has resulted from its use. From f 3ss. to f 3ij. mixed in f viij. of water, and sweetened with a little syrup, may be taken in the course of the day, in divided doses.

But the most important use of chlorine is in its gaseous form, as a fumigation, for neutralizing putrid miasmata, and correcting the infectious atmosphere of hospital wards and rooms in which have been cases of contagious fevers. For these purposes it is better adapted than the common hydrochloric acid gas; but as both of them are highly deleterious to animal life, they should be employed in such apartments only as the sick can be removed from while the gas is extricated. The chlorine is easily procured by pouring f 3vj. of strong sulphuric acid on a mixture of 3iv. of pulverized peroxide of manganese, and 3 viij. of dried common salt, in a china cup, which should be placed in a pipkin of hot sand. The doors of the room which is to be fumigated must be kept shut for two hours after the cup or cups with this charge are placed in it; then be thrown open, and a free current of air permitted to pass through the apartment. By this process the offensive odour of the sick room is destroyed, the chemical constitution of the deleterious atmosphere is altered, and its freshness completely restored.

For the more convenient application of this powerful agent, Morveau has invented what he terms disinfecting or preservative bottles. The apparatus consists of a strong glass bottle or phial, covered with a plate of glass, which is fitted by grinding so as to shut, accurately, the orifice of the vessel. The bottle is fixed in a wooden frame; and the plate of glass kept in its place, and closely applied by means of a screw. If the bottle be of 25 cubic inches of capacity, the charge to be put into it may consist of 372 grs. of peroxide of manganese in coarse powder, 3.5 cubic inches of nitric acid of 1.4 specific gravity, and an equal bulk of hydrochloric acid of 1.134 specific gravity. As soon as the charge is introduced, the glass plate must be firmly screwed down in its place. When the apparatus is to be used, the screw is to be turned so as to allow the gas which is extricated to escape from under the plate of glass; and this must be again screwed down, as soon as the smell of the chlorine is perceptible in the distant corners of the apartment.

Bottles of any dimensions may be used, but the charge must in no case occupy more than one third part of the capacity of the vessel.