1872.] 



History of the Opium Alkaloids, 



27$ 



ceptible change is produced. . The same result follows on boiling for twelve 

 hours (boiling-point 105°) with an inverted condenser attached to prevent 

 loss of water by evaporation ; but if the boiling-point be allowed to rise 

 slowly from evaporation, the mixture being very gently boiled in a long- 

 necked flask, the product gradually acquires the power of giving an imme- 

 diate amorphous precipitate with Na 2 C0 3 ; no large amount of new sub- 

 stances are, however, formed until the boiling-point has risen to about 200°, 

 beyond which point the evaporation cannot safely be pushed. The viscid 

 chestnut-coloured liquid, while still hot, is dissolved in boiling water and 

 allowed to cool ; nothing separates on cooling : when cold, the liquid is 

 nearly neutralized by caustic soda, and then precipitated with Na 2 C0 3 ; 

 the precipitate is collected on filters, drained from mother-liquors, dissolved 

 in weak H CI, and reprecipitated by Na 2 C0 3 , to get rid of traces of unal- 

 tered codeia mechanically retained ; finally, the drained precipitate is ex- 

 hausted with ether. The ethereal solution yields on agitation with H CI a 

 crystalline hydrochlorate, which may be purified by solution in water, 

 fractional precipitation with Na 2 C0 3 , and repetition of the ether process, 

 and finally by recrystallization of the resulting hydrochlorate. 



The portion of the first Na 2 C0 3 precipitate insoluble in ether is dissolved 

 in H CI, and fractionally precipitated by Na 2 C0 3 , to remove colouring- 

 matters as much as possible : the last precipitate, after thorough washing 

 and drying, forms a light buff-coloured amorphous powder that does not 

 soften at 100° when perfectly dry, but clots to a resinous mass if heated in 

 the water-bath while still moist ; it is soluble in alcohol, is precipitated from 

 this solution on addition of ether, and yields salts that have no vestige of 

 crystalline characters. 



Both the crystalline and the non-crystalline hydrochlorates yield on 

 analysis numbers identical with those required for codeia hydrochlorate ; 

 for the reasons developed in the subsequent sections, they are regarded as 

 respectively di- and tetracodeia. 



The filtrate from the original Na 2 C0 3 precipitate contains much un- 

 altered codeia ; by extracting with ether and agitation of the extract with 

 excess of phosphoric-acid solution, a mixture of phosphates is obtained, 

 from which a further quantity of each polymeride is obtainable by simply 

 boiling down the liquid till the boiling-point reaches 200°. 



The hydrochlorate of tetracodeia obtained as above described forms a 

 brownish brittle tar, not fusible at 100° when dry; dried at 100° it yields 

 the following numbers : — 



Specimen A. 0-325 grm. gave 0773 C0 2 and 0-186 H 2 0. 

 „ B. 0-3145 „ „ 0-732 „ 0-185 „ 

 0-1215 „ „ 0-0495 Ag CI. 



