282 
Mr Sears, On the Longitudinal Impact 
Sta tic tests of Steel Specimen. 
Length 
Mean diam. 
Weight 
Density 
16". 
•500". 
•883 lbs. 
485’ 7 lbs. per cub. ft. 
Extensometer test. 
Calibration of Instrument... 1 div. = 1/960". 
Length under test 8". 
Load (lbs.) 
Reading 
Difference 
Return 
Difference 
0 
4-60 
0 
? 
? 
500 
5-19 
•59 
5-25 
•65 
1000 
5-86 
1-26 
5-90 
1-30 
1500 
6-52 • 
1 -92 
6-60 
2-00 
2000 
7-19 
2-59 
7-28 
2-68 
2500 
7-85 
3-25 
7-92 
3-32 
3000 
8-52 1 
3-92 
8-59 
3*99 
3500 
9-20 
4-60 
9-24 
4-64 
4000 
9-85 
5-25 
9-85 
5-25 
Plotting, we see that 4700 lbs. give 6'25 divs. extension. 
E = 
8 x 960 x 470 0 x 1 6 
7 r x 6 '2 5 
= 29,410,000 lbs. per sq. in. 
v = 
29-41 x 10 6 x 32-18 x 144 
485-7 
= 16,750 feet per sec. 
Hence 
