MOTION, MECHANICS, ETC. 

 Fig. 160. 



lor, 



arm of the lever there are eight holes, one inch apart, for 

 the purpose of attaching weights, or the scale pans, when 

 used to illustrate the balance. By this arrangement the 

 levers of the three orders may be readily illustrated ; in the 

 second and third order the pulleys, B, supported by a pillar 

 which is placed on the top of the frame, are used for sup- 

 porting the cord over the lever ; this pillar is movable in a 

 groove, and may be fixed in any position required, and fas- 

 tened by a thumb-screw projecting beneath the frame. 



There are also two levers, c, D, of different lengths, that 

 at one end have a counterpoise consisting of a brass ball, 

 and which may be used as levers of the second and third 

 orders the smaller one being represented in the cut as 

 arranged in the second order, having a weight of six ounces 

 supported at two inches from the axis, balanced by a weight 

 of two ounces supported at six inches from the axis, the 

 cord being supported by one of the movable pulleys, B. 



The Bent Lever is represented at E, supporting a weight 

 on the horizontal arm, of six ounces, at a distance of two 

 inches from the axis, and balanced by a weight of two ounces 



