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bark, which injures its health, and renders 

 it more subject to the attack of vermin ; 

 for it is observed that the vermin more rea- 

 dily prey upon the weak and sickly plant, 

 than the more healthy and vigorous : 

 hence it is easy to see how these two causes 

 act together, to the injury of the tree and 

 fruit; the one rendering them more subject 

 to the attack of the other, which carries 

 them on to total destruction : and it has been 

 observed that the vermin are more destruc- 

 tive in a cold than in a warm season, which 

 has made some imagine it more favourable 

 to their production ; but this is a mistake ; 

 the cold is not directly favourable to the 

 production of vermin, but by causing decay 

 of the vegetable which either produces or 

 fosters them. We see this in all putrifying 

 animal and vegetable substances. If the 

 yermin have penetrated through the inmost 



