The Stinging Power 



into pads on the prickly pears are fero- 

 ciously barbed. Woe to the fingers that 

 handle this kind of velvet too confidently ! 

 At the least touch they are pierced with har- 

 poons whose extraction involves a severe tax 

 upon our patience. Other inconvenience there 

 is little or none, for the action of the barb is 

 in this case purely mechanical. Supposing a 

 very doubtful thing that the Processionary's 

 hairs could penetrate our skin, they would act 

 likewise, only with less effect, if they had 

 merely their sharp points and their barbs. 

 What then do they possess in addition? 



They must have, not inside them, like the 

 hairs of the nettle, but outside, on the surface, 

 an irritant agent ; they must be coated with a 

 poisonous mixture, which makes them act by 

 simple contact. 



Let us remove this virus, by means of a 

 solvent; and the Processionary's darts, re- 

 duced to their insignificant mechanical action, 

 will be harmless. The solvent, on the other 

 hand, rid of all hairs by filtration, will be 

 charged with the irritant element, which we 

 shall be able to test without the agency of the 

 hairs. Isolated and concentrated, the sting- 

 ing element, far from losing by this treat- 



i39 



