ALKALOIDS. 397 



the chloroformic solution is made to evaporate over glass powder, by which 

 process the intimate adhering of the alkaloidal particles is prevented. The 

 residue in capsule A contains practically all the quinine, together with a 

 portion of the alkaloids less soluble in ether ; the residue in B consists almost 

 entirely of these alkaloids, and as about an equal quantity of them is contained 

 in A and B, the weight of B is deducted from that of A. 



Quinine, Quinina, C 20 H 24 N 2 O 2 .3H 2 O = 378. This formula rep- 

 resents the official alkaloid, but it is also known anhydrous, and in 

 combination with either one or two molecules of water. The anhy- 

 drous quinine is a resinous substance, whilst the crystallized quinine 

 is a white, flaky, amorphous or crystalline powder, having a very 

 bitter taste and an alkaline reaction. It is nearly insoluble in water, 

 but soluble in alcohol, ether, ammonia water, chloroform, and dilute 

 acids. When heated to about 57 C. (134 F.) it melts ; at 100 C. 

 (212 F.) it loses 2 molecules of water, the remainder being expelled 

 at 125 C. (257 F.). 



Quinine sulphate, Quininae sulphas, (C 20 H 24 N 2 O 2 ) 2 H 2 SO 4 .7H 2 O 

 = 872. This salt, containing two molecules of the alkaloid in 

 combination with one of sulphuric acid and seven of water, is the 

 common form of sulphate of quinine. It forms snow-white, silky, 

 light and fine, needle-shaped crystals, fragile and somewhat flexible, 

 making a very light and easily compressible mass ; it has a very 

 bitter taste and a neutral reaction ; it is soluble in 740 parts of cold 

 and in 30 parts of boiling water, soluble in 65 parts of alcohol, but 

 nearly insoluble in ether and chloroform ; it readily dissolves in 

 diluted sulphuric or hydrochloric acid. 



Quinine bisulphate, Quininse bisulphas, C 20 H 24 N 2 O 2 .H 2 SO 4 . 

 7H 2 O = 548. This salt is formed when the common sulphate is 

 dissolved in an excess of diluted sulphuric acid. It crystallizes in 

 colorless, silky needles, has a strongly acid reaction, and is soluble 

 in 10 parts of water. 



Quinine hydrochlorate, C 20 H 24 N 2 O 2 .HC1 2H 2 O = 396.4 

 Quinine hydrobromate, C 20 H 24 N 2 O 2 .HBr.2H 2 O = 440.8 

 Quinine valerianate, C 20 H 24 N 2 O 2 .C 5 H 10 O 2 .H 2 O = 444. 



The above three salts are obtained by dissolving quinine in the 

 respective acids ; they are white, crystalline substances ; the first two 

 are easily, the valerianate is sparingly soluble in water. 



Iron and quinine citrate is a scale compound obtained by dissolving 

 ferric hydroxide and quinine in citric acid, evaporating, etc. 



