94 The Potatoe Plague. 



eaten when they have a sufficiency of alkalies, for by their 

 aid they form carbonate of lime, phosphate of lime, silicate of 

 potash, &c., and make their stalks and leaves so hard and 

 strong as to be almost impenetrable to the attacks of many 

 insects that infest them. And their juices are so insipi<J that 

 they are not so well relished by such insects. 



