199 MEDICINAL AND POISONOUS PLANTS 
The chief active principle is aconitine (C;;H,;NO,.) which is 
one of several poisonous alkaloids contained in the plant. 
Medicinally, aconite is used as an external application to re- 
Fic. 177, Il.—Nux Vomica. A, flower-bud. B, same, cut vertically. 
C, floral diagram. JD, fruit cut across. EH, seed, entire. F, same cut 
through embryo between seed-leaves. (Baillon.) 
lieve pain; but from what has been said it is plain that great 
caution should be observed to prevent the introduction of a 
