XII 



POISONS AND STINGS OF PLANTS 

 ANIMALS 



TO give an account of poisonous plants would require 

 a whole volume. Among plants of every degree 

 and kind are many which produce special chemical sub- 

 stances which are more or less poisonous, and yet often 

 of the greatest value to man when used in appropriate 

 doses, though injurious and even deadly if swallowed in 

 large quantity. Plants are laboratories which build up 

 in a thousand varieties wonderful chemical bodies, some 

 crystalline, some oils, some volatile (as perfumes and 

 aromatic substances), some brilliantly coloured (used as 

 dyes), some pungent, some antiseptic, some of the 

 greatest value as food, and some even digestive, similar 

 to or identical with those formed in the stomach of an 

 animal. 



Man, the chemist, every year is learning how to pro- 

 duce in his own laboratories, from coal and wood refuse, 

 many of these bodies, so as to become to an ever- 

 increasing extent independent of the somewhat capricious 

 and costly services of the chemists supplied by nature 

 the plants. In a recent exhibition there was a case 

 showing on one side the various essential oils used to 

 make up a flask of eau-de-Cologne, and specimens of the 

 plants, flowers, leaves, and fruits from which they are 



