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STRENGTH OF MATERIALS 



DESCRIPTION OF THE DROP TEST 



The points of support on which the axle rests daring tests shall be 3 ft. 

 apart from center to center; the hammer must weigh 1640 Ib. ; the anvil, 

 which is supported on springs, must weigh 17,500 Ib. ; it must be free to 

 move in a vertical direction ; the springs upon which it rests must be twelve 

 in number, of the kind specified ; and the radius of supports and of the strik- 

 ing face on the hammer in the direction of the axis of the axle must be ."> in. 



The deflections are measured by placing a straightedge along the 

 axle, properly held at the supports, and measuring the distance from 

 this straightedge to the axle both before and after tin- Mow. The 

 difference between the two measurements gives the deflection. 



