"Take of opium, sliced, twenty ounces; water, one gallon. Pour a small portion of the water upon the opium, and macerate for twelve hours, that it may become soft; then, adding gradually the remaining water, rub them together till they be well mixed, and set the mixture apart, that the feculencies may subside. Lastly, strain the liquor, and evaporate it to a proper consistence."

Extractum Opii Aquosum, Dub. Watery Extract of Opium.

"Take of opium, two ounces; boiling water, a pint. Rub the opium in the water for ten minutes, and, after a little, pour off the solution: rub the residuary opium in an equal quantity of boiling water for the same space of time, pouring off also this solution; and repeat the operation a third time. Mix together the decanted solutions, and expose the mixture in a broad open vessel to the air for two days. Lastly, strain it through linen, and by slow evaporation form it into an extract."

Syn. Extrait d'Opium (F.), Opiums-extrakt (G.), Estratto d'Oppio (I.).

Water takes up a certain proportion of all the constituents of crude opium, but less of the resinous than of the gummy part; and the watery solution contains more of the meconate of morphia, on which depends the remedial quality of opium.4

1 The proper juice, collected by incisions into the flowering stem when the plant is in flower, is preferable to this extract. A good plant of garden lettuce will yield 3ss. of dried juice : one of L. virosa, will yield 3j.

2 Brande's Manual, p. 398.

3 Extractum Opii, P. L., 1824.

4 This extract, however, contains some narcotina; and this is supposed to produce that excitement, which even the aqueous extract occasions previous to its sedative effect. M. Robiquet (Journ. de Pharm. May, 1821,) proposes to free it of this principle, by agitating the extract as soon as it acquires the consistence of syrup with aether; and repeating this agitation with fresh portions of aether, as long as the aether, on distillation, deposits any crystals of narcotine. The extract, thus prepared, contains only morphia, gum, and extractive.

In the Dublin preparation, the quantity of active matter must necessarily be greater than in the London, owing to the employment of boiling water for the second and third triturations. This extract, therefore, differs very little from opium; but, as the inspissation cannot always be conducted exactly in the same manner, its strength must consequently vary.

Qualities. - This extract is inodorous, has a bitter taste, and is of a very deep brown colour. It is not altogether soluble in water; but is not precipitated from its solution by alcohol. It however affords precipitates, with the following substances, which ought not therefore to enter into prescriptions with its solution; viz. solutions of astringent vegetables, the alkaline carbonates, bichloride of mercury, sulphate of copper, sulphate of zinc, acetate and diacetate of lead, and nitrate of silver.

Medical properties and uses. - This extract produces the effects of opium, but with less subsequent derangement of the nervous system. It is therefore supposed to be well adapted for the diseases of children, and very irritable habits. The dose is from gr. j. to grs. vj., for an adult. Officinal preparation. - Syrupus Opii, D.