lower forms of life. Neumann found by experiments on dogs, verified on rabbits and young pigs, that boric acid causes a decided fall in the temperature of the body. Large doses caused diarrhoea and vomiting. Three per cent. solutions injected into the serous cavities caused no inflammation, but when large amounts were injected the animal died from paralysis of the motor nerves and muscles (N. Y. Med. J., Jan. 27, 1883, quoted from Lancet).

Mododewkow reports two fatal cases of poisoning with boracic acid. In one case a pleuritic cavity and in the other a lumbar abscess were washed out with a five per cent. solution of the acid, some of which remained in both cases. The symptoms were, persistent vomiting, hiccough, erythema beginning on the face, slight temporary rise of temperature, diminished cardiac power ending in paralysis. He suggests morphine and stimulants in like cases (Am. J. Med. Sc., April, 1882, quoted from Wratsch, No. 31, 1881).

Boric acid is used externally as an antiseptic in the treatment of wounds, burns, ulcers, abscesses, phlegmonous erysipelas, eczema, etc. It has also been used with advantage in inflammation of the mucous membranes, as aphthæ, diphtheritic inflammations of the mouth, etc. It may be dusted into the external auditory meatus in inflammation of that canal attended with suppuration, and has been used with advantage in inflammation of the conjunctiva (gr. v to aq. f3j). Used as an injection, it appears to shorten the duration of gonorrhoea (H.M.). Made into an ointment with vaseline or cerate (gr. x-xx to 3j) it is an excellent antiseptic dressing for wounds.

SODII BORAS-SODIUM BORATE.

Sodium Borate or Borax occurs as a native product in several localities, the most important of which for a long time was Thibet, in Asia; it is also made artificially by the direct combination of native boric acid with soda. Borax (Na2BO,,10H2O) occurs in the form of hexahedral prismatic crystals, terminated by triangular pyramids, of a sweetish alkaline taste and an alkaline reaction. It is wholly soluble in water, and slowly

effloresces, and has the property of rendering cream of tartar very soluble in water.

Effects and Uses.-Borax is a mild refrigerant and diuretic, and locally an antiseptic, and has emmenagogue virtues attributed to it. Dose, gr. xxx. It has been given in infantile diarrhoea as an enema, and is used externally in cutaneous affections (3j to water Oj as a wash in pruritus and in acne punctata), but especially as a detergent in aphthous affections of the mouth in children, mixed with equal parts of sugar. A piece of borax slowly dissolved in the mouth will often cure acute hoarseness. Glycerite of sodium borate may be made by rubbing up sodium borate 3ij in glycerin Oss; honey of sodium borate may be made by mixing 5j with clarified honey 3j. These preparations are used chiefly as applications to the mouth and throat.

ACIDUM BENZOICUM-BENZOIC ACID.

5

Benzoic Acid (HC,H,O2) is obtained from benzoin by sublimation, or by the action of alkalies; it is also made in Germany from hippuric acid. As obtained by sublimation, it occurs in white, soft, feathery hexagonal crystals, of a silky lustre, and not pulverulent. It has more or less of the agreeable odour of the balsam, a warm, acrid and acidulous taste, is inflammable, sparingly soluble in cold water, rather soluble in boiling water, but perfectly soluble in alcohol, alkaline solutions and fixed oils. It is a constituent of the balsams.

Effects and Uses.-Benzoic acid is a local irritant, destroying minute organisms, possessing decided antiseptic properties, and acting on the general system as a stimulant, with a particular direction to the mucous surfaces. In large doses it increases the circulation and respiration, and is said to be a more powerful antipyretic than salicylic acid. It stimulates the cutaneous and bronchial secretions, and increases the acidity of the urine. In its passage through the system it abstracts nitrogen from the elements of the urea, and passes out with the urine in the form of hippuric acid; hence its use in uræmic poisoning, also in the treatment of ammoniacal urine. It has been used in

diphtheria, erysipelas, etc., with a view to its antiseptic effects, and as an expectorant in chronic bronchial affections. Locally it is used as a dressing for wounds, ulcers, etc., and to prevent animal fats from becoming rancid.. Dose, gr. v-xx.

SODII BENZOAS (Sodium Benzoate) (NaC,H,O,.H2O) is a white amorphous powder, which effloresces on exposure to the air, and has a faint odour of benzoin and a sweetish, astringent taste. It has been used as a substitute for salicylic acid, being less powerful as an antipyretic, but is a safer remedy. It has been used extensively in phthisis, with a view to its antiseptic qualities; also in diphtheria, scarlet fever and the eruptive fevers generally, whooping-cough, etc.; and in acute rheumatism as an antipyretic. From 3j-iij may be given in twentyfour hours.

AMMONII BENZOAS (Ammonium Benzoate) (NH,C,H,O) is made by adding water of ammonia to an aqueous solution of benzoic acid, and occurs in the form of minute white, shining, thin, four-sided laminar crystals, with a slight odour of benzoic acid and a bitterish, saline somewhat balsamic taste and slightly acrid but persistent aftertaste. It is soluble in water and alcohol, and, when heated, sublimes without residue. It is incompatible with the ferric salts. This salt, when taken internally, is probably decomposed by the gastric acids, and produces the constitutional effects of benzoic acid, for which it may be substituted; the ammonia renders it stimulant and antacid, and acceptable to irritable stomachs. It is an excellent remedy for incontinence of urine due to the irritation produced by an alkaline condition of that fluid, and is used with advantage whenever the urine is ammoniacal and loaded with phosphates. Dose, gr. v-xx.

THYMOL.

Thymol (CH,,HO), called also cymylic phenol, is a solid crystalline substance found in the volatile oil (oleum thymi) distilled from the Thymus vulgaris (see p. 195). It is separated by fractional distillation; that portion of the oil which distils above 392° F. is agitated with a concentrated solution of caus

tic soda, and the thymol liberated from the resulting solution by hydrochloric acid. It is purified by rectification, and occurs as large colourless rhombohedral crystals, having an aromatic odour and a hot, aromatic taste; slightly soluble in water, but very soluble in ether and alcohol.

Its

Effects and Uses.-Thymol is a powerful antiseptic. effects are analogous to carbolic acid, and like that agent, when locally applied it produces paralysis of the cutaneous endorgans of the sensory nerves (Lewin; Bartholow). When given internally it produced tinnitus aurium, deafness, reduction of temperature, and often diarrhoea, sometimes nausea and vomiting. In several cases it caused violent delirium and collapse; profuse diaphoresis took place, and the urine was of a dark-green colour, but free from albumen; the sweating was not as marked as that produced by salicylic acid, nor was the antipyretic effect as great. As an antiseptic in inflammations and ulcerations of the mouth it is very useful, and has been used as an inhalation to diminish the expectoration of phthisis, etc. Locally it is used to fulfil the same indications as carbolic acid. Prof. Da Costa recommends crystallized thymol internally in small-pox, in doses of gr. ss, and as a gargle in diphtheria.

ORDER II.—IRRITANTS.

Irritants are medicines which are employed to produce irritation or inflammation of the parts to which they are applied. They may be subdivided into RUBEFACIENTS, EPISPASTICS, SUPPURANTS, and ESCHAROTICS. Rubefacients are used merely to produce redness of the skin. Epispastics, or Vesicants, cause the exhalation of a serous fluid under the cuticle. Suppurants produce a crop of pustules. Escharotics have a chemical action on the tissues with which they are placed in contact, and decompose or destroy them.

RUBEFACIENTS.

Rubefacients are employed to remove congestion and inflammation, to rouse the capillary system in cases of local torpor, to relieve pain and spasm, and as stimulants to the general

system in coma, syncope, asphyxia, etc. They are adapted to cases in which a sudden and powerful, but transient, action is called for; but they may be also employed where a slight and long-continued action is desired. In removing congestion and inflammation, rubefacients act by stimulating the capillary vessels of inflamed parts, and thereby restoring their tone and elasticity. They are useful chiefly in the forming stages or in light grades of inflammation. They are very serviceable local anodynes when applied to painful parts-acting by a substitutive influence. As general stimulants, their efficacy in rousing the system depends partly on their action on the capillary circulation, and partly on the pain which they produce. They are most valuable in the coma or asphyxia resulting from poisons, drowning, etc., and are inferior to blisters in the cerebral oppression which occurs in fevers, inflammations of the brain, etc.

Rubefacients are usually applied till pain and redness supervene. If kept too long on the skin, many of them will produce vesication and even gangrene; and in cases of coma particularly, caution is required, as the patient may not feel them till dangerous inflammation has occurred.

SINAPIS ALBA-WHITE MUSTARD.

SINAPIS NIGRA-BLACK MUSTARD.

MUSTARD SEED are obtained from two varieties of Sinapis -S. nigra, or Black Mustard, and S. alba, or White Mustard (Nat. Ord. Cruciferæ), small annual European plants, cultivated in our gardens. S. nigra has become naturalized in some parts of the United States. Black-mustard seed are small, globular, of a deep-brown colour externally, and internally yellow. They are inodorous, except in powder; and when rubbed with water exhale a very strong, pungent smell. Their taste is bitterish, hot, and pungent. White-mustard seed are larger, yellowish externally, and of a less pungent taste, owing to the presence of a mucilaginous substance in their skin. The powder of both varieties (commonly called flour of mustard) is yellow, and is often adulterated with coloured wheaten flour. Both