These are given to correct acidity in the system. They are soda, ammonia, chalk, and magnesia.

774. Soda, Carbonate of, and Sesquicarbonate of Soda

Soda, Carbonate of, and Sesquicarbonate of Soda, are antacids and deobstruents.

They are _used internally_ in acidity of the stomach and dyspepsia.

_Dose_ of both preparations, from 10 grains to half a drachm.

775. Antalkalies.

These are given to neutralize an alkaline state of the system. They are citric acid, lemon juice, and tartaric acid.

776. Citric Acid

Citric Acid is used to check profuse sweating, and as a subst.i.tute for lemon juice when it cannot be procured.

_Dose_, from ten to thirty grains.

777. Tartaric Acid

Tartaric Acid, when largely diluted, forms an excellent refrigerant beverage and antalkali. It enters into the composition of extemporaneous soda and Seidlitz waters.

_Dose_, from ten to thirty grains.

778. Escharotics.

These are remedies used to destroy the vitality of a part. They comprise lunar caustic, bluestone, and solution of chloride of zinc.

779. Bluestone, or Sulphate of Copper

Bluestone, or Sulphate of Copper, is used in a solution of from four to fifteen grains to the ounce of water, and applied to foul and indolent ulcers, by means of rag dipped in it. It is rubbed in substance on fungous growths, warts, &c., to destroy them.

_Caution_.--It is a poison.

780. Lunar Caustic; or Nitrate of Silver

Lunar Caustic; or Nitrate of Silver, is an excellent remedy in erysipelas when applied in solution (one drachm of the salt to one ounce of water), which should be brushed all over the inflamed part, and for an inch beyond it. This blackens the skin, but it soon peels off. To destroy warts, proud flesh, and unhealthy edges of ulcers, &c., it is invaluable; and as an application to bed sores, pencilled over with a solution of the same strength, and in the same manner as for erysipelas.

_Caution_.--It is a poison.

781. Solution of Chloride of Zinc,

Solution of Chloride of Zinc, more commonly known as Sir William Burnett's "Disinfecting Fluid," is a valuable escharotic in destroying the parts of poisoned wounds, such as the bite of a mad dog. It is also very useful in restoring the hair after the scalp has been attacked with ringworm; but its use requires extreme caution, as it is a powerful escharotic. In itch, diluted (one part to thirty-two) with water, it appears to answer very well.

_Caution_.--It is a most powerful poison.

782. Mechanical Remedies.

These comprise anthelmintics, demulcents, diluents, and emollients.

783. Anthelmintics.

These are medicines given for the purpose of expelling or destroying worms. They are cowhage, scammony, male fern root, calomel, gamboge, tin, and turpentine.

784. Cowhage

Cowhage is used to expel the round worm, which it does by wounding it with the fine p.r.i.c.kles.

_Dose_ of the confection, for a child three or four years old, a teaspoonful early, for three mornings, followed by a dose of castor oil. (_See par_ 491.)

The mechanical anthelmintics are strictly confined to those agents which kill the worm in the body by piercing its cuticle with the sharp darts or spiculae of the cowhage hairs, or the fine metallic points of powdered tin (_pulvis stanni_). When these drops are employed, they should be given in honey or treacle for ten or fifteen days, and an aperient powder every fourth morning, to expel the killed worms.

[TO-DAY, HE HAS DELUSIVE DREAMS OF HEAVEN.]

785. Male Fern Root

Male Fern Root is a powerful anthelmintic, and an astringent. It is used to kill tapeworm.

_Dose_, three drachms of the powdered root mixed in a teacupful of water, to be taken in the morning while in bed, and followed by a brisk purgative two hours afterwards; or from a tablespoonful to a winegla.s.sful, according to age, to be taken early in the morning.

(_See par 569_).

786. Gamboge

Gamboge is a powerful drastic and anthelmintic.

It is _used internally_ in dropsy, and for the expulsion of tapeworm; but its use requires caution, as it is an irritant poison.

_Dose_, from two to six grains, in the form of pills, combined with colocynth, soap, rhubarb, or bread-crumbs.

787. Demulcents.

These are used to diminish irritation, and soften parts by protecting them with a viscid matter. They are tragacanth, linseed, marsh-mallow, mallow, liquorice, arrowroot, isingla.s.s, suet, wax, and almonds.