COMPOSITION 469 



Subjoined is a list of these opium alkaloids, arranged 

 according to their chemical composition : 



Hydrocotarnine, . . C 12 H 15 N0 3 Papaverine, . C 21 H 21 N0 4 



Morphine (12 per cent.), C 17 H 19 N0 3 Meconidine, C 21 H 23 N04 



Oxymorphine, . , C 17 H 19 N0 4 Laudanosine, C 21 H 27 N04 



Codeine . . . C 18 H 21 N0 3 Cryptopine, C 21 H 23 N0 5 



Thebaine, . k . C 19 H 21 N0 3 Narcotine, . C 22 H 23 NO 7 



Laudanine, . . . . ' ... C 20 H 25 N0 4 Lanthopine, C 2 3H 25 N0 4 



Protopine, . . . C 20 H 19 N0 5 Narceine, . C 23 H 29 N0 9 



Some of these alkaloids, such as codeine and oxymorphine, 

 are derivatives of morphine. (1) The codeine series is pre- 

 pared from morphine by the addition of alcohol radicles ; 

 others are got by (2) oxidation ; (3) others by dehydration. 



Opium alkaloids differ greatly in their action. Morphine 

 is analgesic, and more or less hypnotic. Thebaine is stimu- 

 lant and convulsant, and allied to strychnine. The best 

 known of the others oxymorphine, papaverine, codeine, 

 and narcotine form a series, in which the first resembles 

 the narcotic morphine, and the last the tetanising thebaine. 



Morphine and its salts are got by macerating opium in 

 successive portions of water, which dissolve the morphine 

 meconate ; calcium chloride is added to the solution ; 

 calcium meconate precipitates, and morphine hydrochloride 

 remains in solution, from which, when concentrated, the 

 morphine salt crystallises, is subjected to pressure in flannel 

 or stout calico, thus removing narcotine and colouring 

 matter, and is redissolved in hot water, and repeatedly 

 crystallised. By the use of animal charcoal colouring 

 matter is removed ; while, to get rid of codeine, ammonia 

 is added to the watery solution, when pure morphine is 

 precipitated. 



Morphine crystallises in minute, transparent, right rhombic 

 prisms, usually arranged in tufts. It has an intensely 

 bitter taste and an alkaline reaction. It is soluble in 

 ether, benzol, and chloroform ; dissolves in 1000 times 

 its weight of cold water, in 400 of boiling water, and still 

 more readily in oils, caustic alkalies, and weak acids, with 

 which it forms crystallisable and usually soluble salts. 



Morphine hydroehloride (C 17 H 19 N0 3 .HC1.3H 2 0) is prefer- 

 able to the alkaloid on account of its solubility, is the salt 



