288 MATERIA MEDIC A AND THERAPEUTICS. 



LOGANIACE^E. 



Nux Vomica Nux YOMICA. The seeds of 

 Strychnos Nux vomica. Imported from the East Indies. 



Characters. Nearly circular and flat, about an inch in 

 diameter, umbilicated and slightly convex on one side, ex- 

 ternally of an ash- grey colour, thickly covered with short 

 satiny hairs, internally translucent, tough and horny ; taste 

 intensely bitter ; inodorous. 



Composition. Nux vomica seeds contain two alkaloids : 

 2 to '5 per cent, of trychnia f and '12 to TO per cent, of hrucia* 

 united with a crystalline acid, strychnic or igasuric acid, with 

 the ordinary constituents of seeds. 



Brucia, C2 3 H 26 N 2 4 , occurs in colourless prisms, pearly 

 flakes, or masses. It is soluble in alcohol ; much more soluble 

 in water, less bitter, 38 times weaker, and 3 times slower 

 physiologically than strychnia. 



Preparations of Nux Vomica. 



1. Extractum Nucis VomicsB. Spirituous. 16 in 1. 

 Dose, % to 1 gr. 



2. Tinctura Nucis VomicsB. 1 in 10. Dose, 5 to 30 min. 

 From Nux Vomica is made : 



Strychnia.. Source. Made from Nux vomica by 



(1) adding a solution of Acetate of Lead to a concentrated 

 tincture, so as to precipitate the colouring matter, etc. ; 



(2) adding Ammonia to the solution, to precipitate the alka- 

 loids ; (3) dissolving out the Brucia by boiling Spirit, and 

 crystallising out the Strychnia by evaporation and cooling ; (4) 

 purifying by repetition of process (3). 



Characters. Strychnia, C 2l H 2 2N 2 02, occurs in very small 

 colourless prisms, inodorous, intensely bitter (but not to be 

 tasted by the student except in very weak solutions). Solu- 

 bility, 1 in 6,500 of cold, in 2,500 of boiling water. 

 Impurity. Brucia, giving red with HNCV 

 Dose. fa gr., gradually increased to $ gr., always in solution. 



Preparation of Strychnia. 



Liquor Strychnia.. 4 gr. to 1 fl.oz. of Spirit, Water, and 

 Diluted Hydrochloric Acid. Dose, 4 to 10 min. 



ACTION AND USES. 

 1. IMMEDIATE LOCAL ACTION. 



Externally. Strychnia is a powerful antiseptic, but is too 

 poisonous to be applied to wounds. 



