MORPHINE, an alkaloid occurring in 'opium, and constituting from 3 to 20 per cent of the crude drug depending upon where it originated. It has the chemical formula H2O. In the crude opium phine exists in the form of two salts — the ,meconate and sulphate of morphia; and as both of these salts are soluble in water their ery from the opium is of the simplest. In the preparation of morphine the opium is digested with water at 100° F., common chalk is added, and the solution is evaporated to a small bulk. Calcium chloride in slight excess is then added, to precipitate the meconic acid that the extract contains, and after filtration the solution is evaporated. Calcium meconate separates out first, after which crystals of the hydrochlorides of Morphine and codeine are deposited. The latter crystals are re-dissolved in water and decomposed with ammonia, the morphine with a little codeine being thereby precipitated while most of the codeine remains in solution. The codeine is separated from the morphine by dis solving it with ether. Morphine dissolves in 10,000 parts of cold water, and in 500 parts of boiling water. It is also readily soluble in hot alcohol, but is insoluble in ether, benzene and chloroform. It is bitter and very poisonous, and crystallizes in small rhombic prisms, or needle-like crystals. Morphine acts as a base toward acids, and numerous salts of the alka loid are known. In medicine, morphine is usu ally administered in the form of the sulphate or some other salt. When morphine is heated
with hydrochloric acid in a dosed tube, for two or three hours at a temperature of about 290° F. it loses a molecule of water and it be comes converted into another alkaloid which has the formula C,,HoIst0, and is known as aapomorphine.' is also poison ous. Its salts, when administered in small doses, however, do not act as a narcotic, hut as a powerful emetic. Special attention has been paid, by chemists, to the positive identifi cation of morphine, owing to the frequent im portance of such identification in medical juris prudence. The subject is full of technical difficulties, especially when (as is commonly the case) morphine, if present, is mingled with large quantities of animal tissue, from which it must be separated before the tests are ap plied. Many such tests are known, of which the following are the most familiar: (1) A neutral solution of a ferric salt, when added to a neutral solution of a morphine salt, gives a blue color which is destroyed by heat, by alcohol and by acids. (2) If iodic acid and starch are added to a weak solution of a mor phine salt, and a weak solution of ammonia is floated upon the mixture, a brown ring below a blue ring will be formed at the bounding surface that separates the liquids from each other. Consult Autenrieth, W. (Warren's trans lation), 'Laboratory Manual for the Detection of Poisons and Powerful Drugs' (Philadelphia 1915).