THE LEVER. 197 



Frederick was the first to ask an explanation 

 of this wonder. How can it be^ that a thing 

 like that can have so much power !" 



That/' I replied, is the simplest of the 

 mechanical powers, and is called a lever. 

 You see that he placed the block, on which 

 the pole pressed, as near the tree as he could ; 

 because — now attend- — just so much as the 

 part of the lever on this side the block is longer 

 than that beyond it, which goes under the tree, 

 so much more power has the operator with it." 



As my explanation seemed to want some- 

 thing to make it satisfactory to my hearers, 

 I determined to call experiment to our aid. 



There," said I, ^^lies an arm of the tree; see if 

 you can lift up the thick end with your hands." 



They tried ; but could by no means stir 

 it. I desired one of them, then, to take a 

 light pole and a block to assist him. He did 



