14 POISONOUS PLANTS 



In describing plants as " poisonous," it must be 

 borne in mind that the word " poison " is a purely 

 relative term ; and if it seem to convey the idea of 

 "deadliness," such is, as a rule, only applicable to 

 it in its more concentrated form as prepared by 

 chemists. Thus, e.g. children have been made ill 

 by eating too many leaves of the common sorrel, 

 which is perfectly harmless as a salad plant ; but 

 the pleasant acidity is due to the presence of 

 binoxalate of potash ; which, when sold as " salts 

 of lemon " for taking out ink-stains, is a dangerous 

 substance. 



The following is the definition of a Poison as 

 given by Mr. Alexander Wynter Blyth : — "A 

 substance of definite chemical composition, whether 

 mineral or organic, may be called a poison, if it is 

 capable of being taken into any living organism, 

 and causes, by its own inherent chemical nature, 

 impairment or destruction of function." 



The late Dr. B. W. Richardson observed that 

 poisons are not always so bad as they are made out 

 to be, bad as they are ; and he quoted a saying 

 from our great national dramatist, Shakespeare : — 



" There is a soul of goodness in things evil, 

 Would man observingly distil it out." 



Thus a large number of substances, which are very 

 poisonous if taken in any quantity, become valuable 

 medicines in the hands of skilful practitioners. 



