394 CONSIDERATION OF CARBON COMPOUNDS. 



insoluble in ether and chloroform, very slightly soluble in cold 

 water, soluble in 300 parts of cold and 36 parts of boiling alcohol ; 

 heated for some time at 100 C. (212 F.) it becomes anhydrous ; at 

 254 C. (489 F.) it melts, forming a black liquid ; heated with 

 excess of hydrochloric acid for some hours, under pressure, to 150 C. 

 (302 F.), it loses water, and is converted into apomorphine, C 17 H 17 

 NO 2 , a crystalline, solid alkaloid, valuable as an emetic. Apomor- 

 phine hydrochlorate, C 17 H 17 NO 2 .HC1, is official; it is a white salt, 

 which turns green when exposed to the air, especially in the presence 

 of moisture. 



The above-mentioned process for the quantitative estimation of 

 morphine in opium may be used for its manufacture; the crude 

 morphine thus obtained is purified by crystallization. 



Morphine combines with acids, and of the salts are official : 



Morphine acetate, Morphinse acetas, C 17 H 19 NO 3 .C 2 H 4 O 2 .3H 2 O. 



Morphine hydrochlorate, Morphinae hydrochloras, C 17 H 19 NO 3 .HC1.3H 2 O. 

 Morphine sulphate, Morphinse sulphas, (C 17 H 19 NO 3 ) 2 H 2 SO 4 .5H 2 O. 



The above three salts are white, and soluble in water. 



Analytical reactions : 



1. Morphine or a morphine salt sprinkled upon nitric acid assumes 

 an orange-red color, and then produces a reddish solution, gradually 

 changing to yellow. (Plate VII., 1 .) 



2. Neutral solution of ferric chloride causes a blue color with 

 morphine or with neutral solutions of morphine salts ; the color is 

 changed to green by an excess of the reagent, and is destroyed by 

 free acids or alcohol, but not by alkalies. (Plate VII., 2.) 



3. A fragment of iodic acid added to a strong solution of a mor- 

 phine salt is decomposed, with liberation of iodine, which imparts a 

 violet color to chloroform upon shaking the latter with the mixture. 



4. A mixture of 2 parts of morphine and 1 part of cane-sugar 

 added to concentrated sulphuric acid gives a rose-red color. 



5. Morphine dissolves in cold, concentrated sulphuric acid, forming 

 a colorless solution, which, after standing for several hours, turns 

 pink or red on the addition of a trace of nitric acid. 



6. Aqueous or acid solutions of morphine salts are precipitated by 

 alkaline hydroxides ; the precipitated morphine is soluble in potas- 

 sium or sodium hydroxide, but not in ammonium hydroxide. 



7. Neutral solutions of morphine afford yellow precipitates with 

 the chloride of gold or platinum, with potassium chromate or dichro- 

 mate, and with picric acid, but not with mercuric chloride. 



