1. Hard soap. (Part ii.)

2. Soft Soap. (Ibid.)

Variety. Liniment of ammonia. (Part iii.)

3. Liniment of Limewater. (Ibid.) h. Solid vegetable substances. It is necessary to notice in this place the solid proximate principles only of the vegetable substances which are officinal, or employed as pharmaceutical agents. The constituents of the whole of them are - carbon, hydrogen, oxygen, and nitrogen, in different proportions.

h Sugar. (Part ii.) It is soluble in nitric acid, decomposing it and forming oxalic acid. When treated with chlorine, sugar is changed into malic acid.

Varieties, a. Sugar of figs, found concrete on the outside of the dried fruit.

Annals of Phil. vol. v. p. 99. 2 See London Med. Repository, vol. iii. p. 382. 3 Berzelius.

b. Sugar of grapes, - found crystallized in some kinds of raisins. When artificially extracted from the juice of the grape, it is white and crystallized, but less sweet than common sugar. Pure cane sugar is a compound of 42.85 carbon + 6.35 hydrogen + 50.8 oxygen.1 c. Sugar from starch: - its crystals are small spherical granules. When dissolved in water, it ferments with the addition of yest.

d. Mushroom sugar:-its crystals are four-sided prisms, with square bases; very crystallizable : digested with nitric acid, it yields abundance of oxalic acid.

e. Manna? besides a very pure saccharine matter, which has been named mannite, it contains mucilage, and a nauseous substance to which it owes its purgative properties. When digested with nitric acid, it yields saclactic as well as oxalic acid. It does not ferment like sugar.

2. Sarcocoll is usually in oblong, semi-transparent, yellow globules, which have a bitter sweet taste, and an odour resembling in some degree that of anise seed. It does not crystallize. Soluble in water and alcohol. Its aqueous solution is precipitated by tannin. Treated with nitric acid, it yields oxalic acid.

Variety. Liquorice? dissolves in nitric acid, and forms tannin; and, when treated with sulphuric acid, yields about one fourth of its weight of charcoal. It is not susceptible of fermentation.

3. Gum. (Part ii.)

Officinal. Acacia Gum.

Varieties, a. Gum Senegal,-in larger masses than gum arabic, and darker coloured. It is often mixed with gum arabic.

b. Gumkuteera,-in loose, wrinkled, transparent drops, inodorous and insipid; scarcely soluble in cold water, but completely so in boiling water.

c. Mucus,-inodorous, insipid, soluble in water, insoluble in alcohol; not precipitated by silicated potash, but precipitated by alcohol in a fibrous state.

Officinal. Linseed mucus, Quince-seed mucus, Marsh-mallow mucus.

4. Cerasin. This substance, which was formerly confounded with gum, is supposed to be the produce of the Astragalus tragacantha. (For its physical properties, see Part ii.) With nitric acid it yields saclactic, malic, and oxalic acids.

Officinal. Tragacanth.

Varieties, a. Cherry-tree gum,-partially soluble only in water. When treated with nitric acid, it yields saclactic acid.

b. Congo gum?

1 Prout.

c. Dominica gum,-in large masses like stalactites, brittle, light yellowish brown, translucent. It contains three parts of cerasin and one of gum.

d. Bassora gum.

Variety. Salep,-from the bulb of Orchis mascula.

5. Ulmin.1 This is a spontaneous exudation from the elm; but, as Berzelius has hinted, is probably a component of every bark. It is solid, black, hard, shining, and insipid. It is sparingly soluble in water, but does not form mucilage; nearly insoluble in alcohol; precipitated by nitric acid and chlorine, in the state of resin.

1. So named by Dr. Thomson.

6. Inulin is obtained from the Inula helenium in the form of a white powder, which is insoluble in cold water and in alcohol. It is soluble in boiling water, forming a mucilaginous solution; but precipitates as the solution cools. With iodine, it forms a greenish-yellow, perishable compound. Treated with nitric acid, it yields malic and oxalic acids.

Officinal. Elecampane root.

7. Starch. (Part ii.)

Varieties, a. Potato starch has a perceptibly crystallized aspect; is more friable and heavier than common starch.

b. Indian arrow-root has all the properties of common starch; prepared from the roots of Maranta arundinacia.

c. Sago, in gray granules. It is the prepared pith of a palm, the Cycas circinalis.

d. Casava, prepared from the root of the Iatropha Manihot.

e. Tapioca, in granules.

All these varieties of starch are very nutritive and excellent food for the sick and convalescent.

8. Gluten is of a gray colour, nearly insipid, and inodorous, very tenacious, ductile, and elastic; partially soluble in water, and soluble in acetic and muriatic acid. Insoluble in alcohol and ether. M.Taddei has ascertained that it may be decomposed into two principles - which he has named Gliadine and Zimome. When gluten is rubbed with powdered guaiac, a blue colour is evolved. When treated with nitric acid, it yields oxalic acid.

9. Fibrin is tasteless, fibrous, elastic, and resembles gluten. It is insoluble in water, alcohol, and diluted alkali; but is soluble in acids, particularly nitric acid. It soon putrefies.

10. Extractive is obtained by evaporating aqueous vegetable infusions to dryness. It has a strong taste; and is soluble in water; but insoluble in alcohol and ether, unless when the extractive is united with resin. It is precipitated from its solutions by chlorine and protochloride of tin, but not by gelatin, Officinal. Catechu, most barks, etc.

11. Tannin (tannic acid) is colourless and inodorous when pure; has an astringent taste, is soluble in water, in ether, and in alcohol of 0.810. It gives an acid reaction with litmus, and is usually combined with gallic acid. It is precipitated by gelatin. It is a compound of 110.16, or 18 eq. of carbon + 9, or 9 eq. of hydrogen + 96, or 12 eq. of oxygen. Equivalent = 215.16.