Prep. Chlorinated lime, ten pounds; rectified spirit, thirty fluid ounces; water, three gallons; chloride of calcium, broken into fragments, two ounces; slaked lime, a sufficiency; sulphuric acid, a sufficiency; distilled water, nine fluid ounces. The rectified spirit and water are distilled with a mixture of slaked and chlorinated lime; the distillate well agitated with water, and the lower stratum, which is crude chloroform, separated, re-peatedly washed with successive portions of water, and well shaken with its own volume of sulphuric acid; the layer of chloroform is again separated, mixed with chloride of calcium and slaked lime, and purified by redistillation. Chloroform may be produced by several processes, but the above probably yields it purer and more advantageously than any other. When chlorine, from chlorinated lime, acts upon alcohol, many complicated and ill-understood decompositions ensue; the principal product, however, seems to be chloroform.

Prop. & Comp. Chloroform is a colourless heavy liquid, with a peculiarly agreeable, fruity, ethereal odour; sp. gr. from 1.48 to 1.496; but slightly soluble in water, sinking readily in that fluid; it mixes with alcohol and ether in all proportions; neutral in reaction; when rubbed on the skin it quickly evaporates, and, if pure, leaves no odour. Chloroform is a powerful solvent of caoutchouc, gutta percha, many resins, fats, and alkaloids, also of iodine and bromine. Composition (C2 H, Cl3), or a terchloride of formyl (C2 H). When exposed to air and light, it is apt to decompose, hydrochloric acid and free chlorine being formed: it is stated that when chloroform is purified with oil of vitriol, it is more liable to undergo this change, and that redistillation with carbonate of baryta gives it stability. Chloroform is not coloured by agitation with sulphuric acid, and evolves no gas when potassium is dropped into it, indicating the absence of oily matters or any oxygen compounds. Chloroform is decomposed by fixed alkalies; by an alcoholic solution of potash it is resolved into formate of potash and chloride of potassium.

Off. Prep. Linimentum Chloroformi. Liniment of Chloroform. (Chloroform, two fluid ounces; liniment of camphor, two fluid ounces.) [Purified chloroform, three troy ounces; olive oil, four troy ounces. U. S.]

Spiritus Chloroformi. Spirit of Chloroform. (Chloroform, one fluid ounce; rectified spirit, nineteen fluid ounces.) Sp. gr. 0.871. [Purified chloroform, one troy ounce; stronger alcohol, six fluid ounces. U. S.]

Therapeutics. When taken internally, chloroform appears to act as a narcotic and antispasmodic, not unlike ether; its sedative effects, however, are more distinctly marked, and it produces in large doses a general diminution of sensorial power, with drowsiness, and without exhilaration or acceleration of the pulse. It has been employed in spasmodic affections, as spasmodic coughs, asthma, cholera, lead colic, and hysteria; it is also stated to act as a valuable sedative in cancer, neuralgia, and other painful affections, and it is even asserted to be antiperiodic, relieving sometimes when bark and quinine have failed.

Externally, it has been used in medicine to allay pain and irritation in neuralgia, and certain skin affections attended with troublesome itching. For all these purposes, however, its application is very limited; its chief employment being in the form of vapour, for the production of its anaesthetic effects.

When inhaled in small doses, it produces a slight species of inebriation, with some impairment of vision and common sensibility, consciousness remaining. The sensations produced by these small doses are usually of a pleasurable character; carried to this extent, it may be employed in the treatment of spasmodic and neuralgic affections.

If the inhalation be continued longer, the patient passes into a dreamy state, sometimes with considerable mental excitement, but with loss of common sensibility; it may be given to this extent when employed in natural labour: from these effects the patient soon recovers on the cessation of the administration of the vapour.

If the inhalation be carried still further, the patient loses the power of voluntary motion; there is an inclination of the eyes upwards, complete suspension of the mental faculties, with slight contraction of the muscles and rigidity of the limbs. Although at this stage common sensibility appears quite destroyed, yet on the performance of surgical operations there may be indications expressive of pain in the features, and even moaning and inarticulate cries. When this condition has been kept up for some time, and the winking of the eyelids very much diminished, then is the proper period for the performance of surgical operations.

If the effects be carried further, complete relaxation of the voluntary muscles takes place, but the sphincters remain contracted, the respiration goes on, though accompanied with slight stertorous breathing, the glottis continues sensible, but the sensibility of the pharynx appears to be diminished, so that in operations about the mouth blood frequently finds its way into the stomach; the iris is much less sensitive to light, but not contracted. When the relaxation of the muscles has fully taken place, then the reduction of dislocations and hernia may be effected.

If the inhalation is continued beyond this stage, symptoms indicative of danger succeed: the breathing becomes very stertorous and slow, and may altogether cease, and death may take place, sometimes accompanied with convulsions.

Chloroform has been administered in the form of vapour in the treatment of tetanus, hydrophobia, colic, and painful spasmodic affections, as during the passage of renal calculi, or of gall-stones, etc.; in some of these cases its use has been followed by great relief. The first and second set of symptoms above mentioned may be generally produced by administering from half a fluid drachm, to a fluid drachm, and repeating it in a few minutes if this condition is required to be kept up. When the inhalation is suspended, the patient, in the course of five or six minutes, recovers his consciousness, but without remembering anything which has taken place. For the production of complete insensibility and relaxation more chloroform must be employed, and the effects carefully watched. If the inhalation has proceeded too far, ammonia, dashing cold water in the face, or even artificial respiration, must be had recourse to.

In the administration of chloroform, several precautions should be taken. In the first place, the chloroform should be pure, that is, free from oily matter, hydrochloric acid, and uncombined chlorine; it should not be used at all, or if so, employed with the greatest care, for persons suffering from any cerebral disease, or tendency to such, or any organic cardiac affection. It may be administered in vapour either by means of a folded handkerchief applied over the face and nose, or by means of inhalers which are sold for this purpose; and care should be taken that the patient breathes atmospheric air at the same time with the chloroform vapour. Disagreeable symptoms sometimes occur after the inhalation of chloroform, as nausea, vomiting, headache: probably these may occasionally arise from impurities in the preparation.

Ether, and the vapour of some other hydrocarbons, as Amyline, Benzol, Dutch Liquid, Bisulphuret of Carbon, etc, when inhaled, produce effects not unlike those of chloroform, and before the discovery of this latter agent, pure ether was always made use of; the effects of ether appear to be almost identical in kind with those of chloroform, but the quantity required to produce the same effect is much greater, from one fluid ounce to two fluid ounces.

It is stated by Dr. Snow that greater muscular relaxation is produced by ether than by chloroform.

When chloroform is taken into the stomach, or exhibited in the form of vapour, it is absorbed into the blood, and Dr. Snow has discovered its presence in the blood of animals killed by this agent. Its detection can be effected by causing the vapour from the suspected fluid to pass through a red-hot tube, when the chloroform, if present, is decomposed and free chlorine evolved, which may be made to act upon nitrate of silver, or upon starch-paper impregnated with iodide of potassium.

Dose. Chloroform, when given in a liquid state, may be rubbed up with yolk of egg and mucilage, or syrup: the dose may be from 1 min. to 10 min. It is more frequently administered in the form of Spiritus Chloroformi (chloric ether), of which the dose may be from 10 min. to 30 min. or more. Externally it may be employed in the form of Linimentum Chloroformi, or added to other liniments, or as an ointment, made by rubbing together 1 part of chloroform, with about 7 of lard. The doses for inhalation have been already indicated.

Adulterations. Hydrochloric acid and free chlorine, detected by their acid reaction and bleaching power, and by the water with which the chloroform has been agitated, precipitating nitrate of silver. Sometimes an oily matter, formed during the preparation, may be present, detected by its leaving an odour on evaporation, and being coloured by sulphuric acid.

Fousel Oil. Appendix A. Amylic Alcohol. [Alcohol Amyli-cum. Fusel Oil. U. S.] Prop. & Comp. Fousel oil, a product obtained in the distillation of spirit from potatoes, barley, etc. It is much less volatile than ordinary alcohol, and accumulates in the last portions of the liquids submitted to distillation. It boils at 270°, and has a specific gravity of 0.818, and a peculiar unpleasant odour and taste. Fousel oil is the alcohol of the amylic series, the hydrate of the oxide of amyl (C10 H11 O, HO), and has the same relation to amyl as alcohol and wood spirit have to ethyl and methyl. By the action of oxidizing agents it is converted into Valerianic Acid, which corresponds to acetic acid in the ethyl series: -

C10 H12 O2 + O4 = HO, C10 H9 O3 + 2 HO.

It is for the formation of this acid that it is introduced into the Appendix of the Pharmacopoeia.