THE BALANCE 157 



10" wide, another board J4" thick, 10" long and 4" wide, 

 two nuts having a half inch hole, screw eye, four Y% 

 metal screws, iron or soft brass wire No. 12, pieces of 

 tin, old knife blade, one dozen y%" screws ^" long, fine 

 needle. 



a. The illustration shows the balance as it should 

 appear when finished. The base (a) is 12"x 7", the pil- 

 lar (b) isj^" square and 9" high, and is set in a J/" 

 hole in the center of base. The upper end of the pillar 

 should be sharpened to an edge as shown at (k), and a 

 slot sawed in it as shown at (1). The beam (c) is made 

 from a stick %" square and 10" long. Its lower edge is 

 left straight but the other sides are planed so as to make 

 the ends a little larger than half an inch square. The 

 ends are then rounded so that the nuts (e) will screw on 

 snugly. A notch 1" wide and y?" deep is cut in the cen- 

 ter of the bottom edge. This receives the central bearing 

 of the beam. An inch from each end of the beam a 

 notch J4" deep is cut to receive the tray bearings (n). 

 The two tray bearings, as well as the pillar bearing, 

 should have the notches lined with tin as shown at (m) 

 and (o). A pointer (f) made of }4" material, is firmly 

 fastened to the beam by two screws. Its lower end is 

 provided with a needle, colored black so as to be easily 

 seen. The screw eye (h) is placed near the end of the 

 pointer and in the center of the pillar. It should turn 

 easily. When the balance is completed, turn the screw 

 eye so as to hold the pointer firmly, then paste to the 

 pillar back of the pointer, a strip of water paper (g), 

 bearing scale marks 1-16" apart, with the zero mark of 

 the scale directly back of the needle. 



The bearings of the balance are the most important 



