Cascarilline may be prepared from the bark of Croton Cascarilla or C. Eleutheria by the following processes: -

(1) The bark is exhausted with cold water by percolation, precipitated with lead acetate, and the filtrate treated with sulphuretted hydrogen; the filtered liquid, after agitation with animal charcoal, and filtration, is gently evaporated to dryness. The powder is re-dissolved in boiling alcohol, and crystallized by very slow or spontaneous evaporation. (Duval.)

(2) A quantity of coarsely powdered cascarilla bark is covered with a 2 to 3 per cent, solution of oxalic acid and allowed to stand for 12 hours, the mixture being frequently shaken. At the expiration of this period, the temperature of the mixture is gradually raised to 140° F. (60° C), after which it is allowed to cool. Lastly, the liquid is filtered and the marc well pressed. The filtrate is then saturated with ammonia, and evaporated at a low temperature to 2/3 of its bulk. The liquid is again allowed to cool, and a deposit separates, if any has been formed. The liquid is poured into a flask containing pure ether, the whole being shaken for some time. After being allowed to stand for 3 hours or more, the ethereal solution is poured off and distilled, so as to recover the greater part of the ether. The evaporation is completed spontaneously in a current of air, without the application of heat, the result being pure white cascarilline. The ethereal solution contains a small quantity of essential oil, nearly the whole of which passes ! over during the process of distillation; but this in no way prevents the ether from being used for the separation of another batch of the alkaloid.

Colchicine is obtained from the seeds of the meadow saffron (Colchicum avtumnale) by the following process: - Macerate the bruised seeds in boiling alcohol, add magnesia to throw down the alkaloid, digest the precipitate in boiling alcohol, and filter. By cautious evaporation, colchicine will be deposited, and may be purified by re-solution and crystallization in alcohol.

Morphine is the most important alkaloid obtained from opium, itself a product of several species of poppy (Papaver). Cooley gives the following 4 methods of preparing morphine: -

(1) Turkey opium (cut into thin slices), 1 lb., is macerated for 24 hours in 1 qt. water, and the liquid portion is decanted; the residuum is macerated for 12 hours with a second quart of water, and the process is repeated with a third quart of water, after which the insoluble portion is subjected to strong pressure; the mixed liquids are evaporated by water or steam heat to a pint, and filtered through calico; to the filtrate is added a solution formed of 6 dr. calcium chloride, dissolved in 4 fl. oz. distilled water, and the liquid is further evaporated until it is so far concentrated that nearly the whole of it becomes solid on cooling; this is enveloped in a couple of folds of strong calico, and subjected to powerful pressure, the dark liquid which exudes* being preserved for subsequent use; the squeezed cake is next treated with about 1/8 pint of boiling water and the undissolved portion is washed on a paper filter; the filtered solution is again evaporated, and the solid portion thus obtained submitted to pressure as before; if the product is not quite white, this process is repeated a third time; the squeezed cake is now dissolved in 6 fl. oz. of boiling water, and the solution filtered through animal charcoal (if necessary); to the clear solution is added ammonia in slight excess; the crystalline precipitate, which forms as the liquid cools, is collected on a paper filter, washed with cold distilled water, and, lastly, the filter is transferred to a porous brick, in order that the morphine which it contains may become dry. (From the liquids reserved from the expressions, more morphine may be obtained by dilution with water, precipitation with ammonia, re-solution in boiling water, and treatment with a little animal charcoal, etc, as before.)

(2) Hydrochlorate of morphine, 1 oz., is dissolved in 1 pint distilled water, and 5 fl. dr. (or q. s.) ammonia previously diluted with 1 fl. oz. water is added, with agitation; the precipitate is well washed in distilled water, and dried by a gentle heat. By a similar process, morphine may be obtained from its other salts.

(3) A cold aqueous infusion of opium is precipitated with carbonate of sodium in excess; the precipitate is washed, first with cold water, and then with cold alcohol of .85 sp. gr.; the residue is dissolved in weak acetic acid; the solution is filtered through animal charcoal, and precipitated with ammonia; the precipitate is again washed with cold water, dissolved in alcohol, and crystallized. A good process where spirit is cheap. (Merck.)

(4) Opium, 4 parts, is made into a strong infusion with water, q. s.; 1 part lime, reduced to a state of milk with water, is then added; the mixture is next heated to boiling, at once filtered through linen, and treated, whilst still hot, with chloride of ammonium, in fine powder, in slight excess (about 1 oz. to each lb. of opium); the morphine is deposited as the liquid cools, and may be purified by a second solution in lime and precipitation by chloride of ammonium. This process is remarkably simple, and in many points is preferable to any other, either on the small or large scale. (Mohr.)

(5) Pure

The opium is digested in tepid water, and strongly expressed several times. The solution is evaporated down with powdered -carbonate of lime. When about the consistence of a syrup, water is added, and the precipitated meconate of lime is filtered off. The liquid is again concentrated at a gentle heat. When concentrated and quite cold, a solution of chloride of calcium and a little hydrochloric acid are added, and the mixture is left to stand for 15 days. During this time crystals of hydrochlorates of morphine and codeine are deposited. In order to separate these, the crystals are dissolved in water, and treated with dilute ammonia, which precipitates the morphine, leaving the codeine in solution. The morphine is purified by repeated crystallizations in alcohol. When prepared in this way, morphine is often contaminated with a little narcotine, which may be removed by treating with ether, in which morphine is quite insoluble.

Narcotine is prepared from opium by the following methods: - (1) From opium exhausted of soluble matter by cold water, by treating it with water acidulated with acetic or hydrochloric acid, filtering, neutralizing with ammonia, and dissolving the washed precipitate in boiling alcohol; the narcotine is deposited as the liquid cools, and may be purified by solution in ether. (2) By acting with ether on opium previously exhausted by cold water. (Cooley.)

Nicotine is obtained from tobaccoleaves by the processes enumerated below: -

(1) Infuse tobacco-leaves for 24 hours in water acidulated with sulphuric aeid, strain, evaporate to a syrup, add 1/5 of its volume of a strong solution of potash, and distil in an oil-bath at 288° F. (142° C), occasionally adding a little water to assist the process and prevent the too great concentration of the solution of potash in the retort; next saturate the distilled product with oxalic acid, evaporate to dryness, 'digest in boiling absolute alcohol, evaporate the resulting tincture to a syrup, and decompose the oxalate of nicotine thus obtained by adding potash to it in a close vessel, and agitate the mass with ether, repeating the process with more ether until all the nicotine is dissolved out; lastly, distil the mixed ethereal solution in an oil-bath. At first ether comes over, then water, and lastly nicotine, which, towards the end of the process, assumes a yellowish tint. (Ortigosa.)

(2) This chiefly differs from the preceding by the concluding distillation being conducted in a retort, by the heat of an oil-bath, at the temperature of 284° F. (140° C), in a current of hydrogen, for 12 hours; after which, by raising the heat to 356° F. (180° C), the nicotine distils over pure, drop by drop. (Schlosing.)

(3) A tin vessel provided with 2 tubulures is filled with tobacco, which is previously damped with sodium carbonate. One of the tubulures admits a glass tube reaching nearly to the bottom of the vessel; the other is provided with a glass tube merely penetrating the cork. The vessel is made air-tight, placed in a boiling-hot steam bath, and a rapid stream of carbonic acid gas is passed through it, entering the vessel by the longer and leaving it by the snorter tube; the latter dips into a mixture of alcohol and dilute sulphuric acid. In this manner, a large yield of perfectly colourless nicotine is obtained. In order to obtain the pure alkaloid, caustic baryta is added to the solution, the latter is evaporated to dryness, and the pure nicotine is extracted with ether. (Kirschmann.)

Pipeline is obtained from black pepper {Piper nigrum) as follows. The alcoholic extract is treated with a weak solution of caustic potash (1 to 100), and the residue, after being washed with cold water, is dissolved in alcohol; the solution is next agitated with a little animal charcoal, and the filtrate is allowed to evaporate spontaneously; the product may be purified by resolution in alcohol and re-crystallization. (Cooley.)