980 VEGETO-ALKALIES. 



Subsulphate of quinine, the ordinary sulphate of quinine of 

 the shops, crystallizes in tufts composed of fine needles, which 

 are very light, slightly flexible and have a pearly lustre. It 

 requires 740 parts of water to dissolve it at 55", but only 30 

 parts at 212 ; it is very soluble in dilute sulphuric acid. It fuses 

 with the appearance of wax, and loses 1 1 J per cent or 6 atoms of 

 water. The crystallized salt contains 2 atoms of quinine and 8 

 atoms of water to I atom of sulphuric acid. Neutral sulphate of 

 quinine is formed by adding a little sulphuric acid to a solution 

 of the sub-sulphate ; it crystallizes well in rectangular prisms 

 with rectangular or square bases, is soluble in 1 1 parts of water 

 at 55, and fuses in its water of crystallization at 212. It 

 reddens vegetable blues, although its taste is not perceptibly 

 sour but strongly bitter ; it contains 8HO. 



Cinchonine, C 20 H 12 NO. This base crystallizes readily from 

 alcohol in brilliant prisms. It requires 2500 times its weight 

 of boiling water to dissolve it, and is less soluble in cold water. 

 It is but slightly soluble in cold ether ; in its other properties 

 it resembles quinine. Neutral sulphate of cinchonine crys- 

 tallizes also in large octohedral crystals of a rhomboidal base, 

 having a mother of pearl lustre; it contains 8 atoms of 

 water. 



STRYCHNINE AND BRUCINE. 



These alkalies are derived from the Nux vomica class of 

 plants and particularly from the seeds of Strychnos nux vomica, 

 and St. Ignatius 5 bean, the fruit of Strychnos ignatia. To 

 extract them, powdered nux vomica is boiled repeatedly in 

 water, the infusion is concentrated to a syrup and mixed with 

 hydrate of lime in the proportion of 2 ounces of quicklime to 

 1 pound of the nux vomica. The two bases are contained in 

 the insoluble portion of the mass, which is dried and exposed 

 to boiling alcohol. On evaporating the alcoholic solution 

 strychnine crystallizes first, while the brucine and a portion of 

 strychnine remain in the mother liquor. To complete the 

 separation, the bases in the mother liquor are neutralised by 

 greatly diluted nitric acid, and the nitrate of strychnine crys- 

 tallized out, while the salt of brucine remains still in solution 

 being much later of crystallizing. From the salts, purified as 



