IMPACT UPON BEAMS. 
115 
loaded tube were less than those where the empty one was used, 
though the ultimate deflections were a little greater in the former 
case than in the latter. The following experiments are intended 
to show that increasing, to a certain extent, the weight of the 
body struck augments its power of bearing impact. 
Impact on Bodies sustained by Wires. 
Experiments to illustrate the Increase of Power to resist Im¬ 
pulsion, which elastic Bodies acquire by being loaded. 
An iron wire (thickness No, 17) was suspended by one end 
from the top of a room ; the other hanging down with a round 
cast iron ball, having a hole bored through it, affixed to the lower 
end. The striking body, likewise, was a cast iron ball, bored 
in like manner, and having the wire passing through it 
so easily as to form no resistance as it fell. 
In the annexed figure, A B represents the wire fas¬ 
tened at A; B the weight at bottom; C the striking 
weight. In the experiments, C was let fall upon B 
from various distances, C B, to ascertain the heights 
necessary to break the wire when sustaining different 
weights B. 
The weight B had a perforated disc of lead, through 
which the wire passed, laid upon it, to lessen or de¬ 
stroy the elasticity of the impinging bodies. 
Experiments. 
Length 
of wire. 
Weight of 
striking ball 
at C. 
Weight of 
ball at B 
with lead. 
Bore impacts through. 
Broke with 
falling 
through. 
ft. in. 
lbs. 
oz. 
lbs. 
oz. 
feet. 
25 0 
5 
14 
0 
9 
2, 24 , 3, 34, 4 feet. 
1 j 3 
— 
— 
(repeated) 24, 3, 34, 4,44ft. 
5 j 4 - 
24 0 
6 
0 
10 
1 
7 ft.. 
7*1 7 
— 
(repeated, fresh wire,) 6 ft. 
6if 7 
— 
44 
0 
1, 2, 3, 4, 5, 6, 64, 7 ft. ... 
74 
— 
80 
8 
6, 64, 7, 74,8, 84, 9 ft. ... 
94 
— 
—- 
89 
0 
8, 84, 9, 94, 10, 104 ft. ... 
11 
— 
125 
0 
8, 84, 9, 94, 10 ft. 
104 
—- 
40 
0 
10 
1 
3, 4 inches .. 
5 inches. 
— 
80 
8 
2, 3, 4, 5, 6 inch. 
7 do. 
—— 
— 
89 
0 
4, 5 inch. 
6 do. 
24 8 
85 
0 
44 
0 
2 inch. 
3 do. 
Remarks. 
Nolead. 
r It broke one 
-] inch from 
Ctop. 
