MECHANICAL PARADOXES. 



This arrangement is shown at M, and it is, 

 in fact, found by experiment that if L be one 

 square inch and M five square inches, one 

 pound at L balances five pounds at M, and a 

 pound and a half at L lifts five pounds at M. 



On the same principle, if the area at M be 

 one hundred times that at L, or 100 square 

 inches, then a pressure of one pound at L 

 will balance 100 pounds at M. And any other 

 pressure applied at L would be multiplied in 

 the same proportion. Now a man can without 

 difficulty exercise a pressure of sixty pounds. 

 And if he apply this pressure on a pump-handle 

 whose power end is six times as long as its 

 work end, so that the working leverage is six, 

 he can thus put a pressure of 360 pounds on 

 the piston. Pumping water into L at this 

 pressure, when M is one hundred times the area 

 of L, he can make the water in M lift a weight 

 of 36,000 pounds that is, sixteen tons. 



One man, by pumping at a handle, lift 

 sixteen tons ! It sounds magical at the first 

 time of hearing. It seems like cheating Nature. 

 But Nature is a very careful banker, and has 

 never had the worst of a bargain yet. She 

 never cashes a cheque for an amount in excess 

 of the deposits and the security. 



You cannot get out of any machine in one 

 form more power than in some other form or 

 forms is put into it. Indeed, you cannot get 

 quite so much. Whatever power you put 



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