848 



BOTANY AND PHARMACOGNOSY. 



containing three molecules of water of crystallization (C20H24N2- 

 O., + 3H2O), which is official. Some authors consider, however, 

 that there is only one molecule of water of crystallization in this 

 hydrous salt.* The hydrous salt has a M. P. of 57 while the 

 anhydrous crystals melt at 175- Quinine is a strong base, form- 

 ing with acids basic and neutral salts. The neutral sulphate is 

 largely used and is here considered. 



i if*** 



f- 1.. ^ ^ 





I 







Pig. 342. Strychnine sulphate: tetragonal crystals from aqueous solution, in ordinary light, 



showing basal and side aspects. 



There are several modifications of quinine sulphate : ( i ) 

 The neutral sulphate containing eight molecules of water of crys- 

 tallization [(CooHa^N.OJa-HoSO^ + 8HX)], is obtained upon 

 neutralizing the base with sulphuric acid and crystallizing from 

 hot water. (2) Upon exposing the former over sulphuric 

 acid it loses six molecules of water of crystallization giving 

 [(C2oH24N202)o.HoS04 -f- 2H0O]. This same salt is formed 

 upon re-crystallizing (i) from hot alcoholic solutions. (3) The 



O. A. Oesterle, Grundriss der Pharmakochemie. 



