THE WEIGHING MACHINE. 



53 



the lever D, the other end of which is connected by means 

 of an upright rod with the steelyard at F. 



There are two important points gained in this combina- 

 Fig. 53. tion. In the first place, the 



levers multiply the power so 

 much that a few pounds' 

 weight will balance a heavy 

 load of hay weighing a ton 

 or more ; and, in the next, 

 the load resting on both the 

 levers, communicates the 

 same force of weight to the 

 central point, from whatever 

 part of the platform it hap- 

 pens to stand on : for if it 

 presses hardest on one lever, 

 Portable Platform Scale. it bears lighter, at a cor- 



responding rate, on the other. In practice, there are 



Fis. &4. 



Large Platform Scale. 



always two pairs, or four levers, which proceed from each 



