16 BULLETIN 347, U. 8. DEPARTMENT OP AGRICULTURE. 



EQUIPMENT. 



Small jaw crusher. 



Balance (same as used in abrasion test). 



100 c. c. graduate. 



Several 1-pint jars, with metal screw caps. 



Ball mill. 



The ball mill shown in figure 8 consists essentially of the cast-iron 

 casing (AB), split into the two unequal segments (A and B). It 

 revolves in a vertical plane on the shaft (CC) bearing in the pillow 

 blocks (DD) and driven by the pulley (E). The steel shot used for 

 grinding measure 5 inches in diameter and weigh 20 pounds each. 

 Two shot are used in each mill. 



Briquette-forming machine. 



This machine is shown in figure 9 and consists fundamentally of a 

 hydraulic cylinder (A) supporting an iron platform (B) through the 

 piston rod (C). The cylindrical metal die (JD) is provided with a 

 closely fitting plug (E) supported by guide rods (KK). The supply 

 pipe shown in the cut admits water to the cylinder. The lever arm 

 (G) is provided with an adjustable weight (H) consisting of a hollow 

 cylinder partially filled with shot. Details of the metal die are 

 shown in figure 10, in which a small metal stand (A') shaped in the 

 form of a half circle is used in removing the compressed material. 



Small balance weighing to 100 grams and sensitive to 0.1 gram. 



Millimeter scale. 



Drying oven. 



The oven should be equipped with a thermometer and regulating 

 device for maintaining a constant temperature of 100° C. for several 

 hours. 



Desiccator and calcium chloride. 



Shellac dissolved in alcohol. 



Page impact machine for testing cementing value. 



The machine as shown in figure 11 consists essentially of the 

 motor (A) driving the cam shaft (E) by means of a worm gear at the 

 rate of 60 revolutions per minute. The plunger (H), weighing 

 one-half kilogram, is held in position on the briquette (/) by means 

 of two spiral springs, one on each side of the sleeve in which the 

 plunger slides. The lever (L) is pivoted on the plunger through a 

 slot cut in the sleeve. It carries a brass pencil at one end, while the 

 other is provided with means for adjusting the height of the pencil 

 with reference to the drum (M). The hammer (G), weighing 1 kilo- 

 gram, is raised by the pin (F) which slides upon the face of the cam 

 (E). The pin is provided with a thumbscrew and locknut (F) for 

 adjusting and maintaining its vertical position. The cam (E) is also 

 provided with means for imparting at each revolution a slight motion 

 to the drum (If), so that the drum makes one complete revolution for 

 each 100 blows of the hammer. 



