SHORT NOTES ON PROFESSIONAL SUBJECTS. 
147 
The 161b. cartridge being only 12 ins. long, the C crusher was a little behind 
the centre of the shot, but nearly in the position of least windage. The pressure 
on this crusher was greater than that on the axial crusher, A , in nine out of the 
twelve rounds with E.L.G. and L.G. powders, and equal to it in one of the other 
three. The two L.G. powders gave, on the whole, a rather less pressure than the 
E.L.G. 
In making experiments to determine the comparative effects of L.G. and E.L.G 
powders, it is difficult to obtain exact indications of the difference due solely to 
the size of grain (by which principally E.L.G. is intended to be distinguishable 
from L.G.), on account of their generally differing also in the very important quality 
of density, and occasionally in other points—such as the nature of charcoal, and 
the tendency to a flaky form of grain. It is however important to ascertain whether 
E.L.G. is liable under any conditions to be more destructive than L.G., or vice 
versa, as it affects the practicability of making these two powders interchangeable 
for service or battering charges. 
Up to the end of December, 1870, the Committee had fired 44 rounds of E.L.G. 
and L.G. suitable for the purposes of this comparison—viz., 24 with the 10-inch 
gun and 4001b. shot; 8 with.the 8-inch gun and 1801b. shot; and 12 with the 
same gun and a 69 lb. shot; the average results are as follow :— 
10 -inch Gun 9 Smooth-bore. 
O 
Pi "2 
Q3 rQ 
& E3 
JS £ 
N .In 
§ 8 
Pressure by 
crusher gauge at 
400 lb. Shot. 
f density, 1*742; 60lbs.... 
a o 
1 " 
o 
ai 
A. 
B. 
C. 
1 
6 
f.s. 
1327 
tons. 
61 
tons. 
32 
tons. 
26 
E.L.G. J 
/, 1733; „ ... 
6 
1330 
48 
31 
25 
! 
L h 1-6.75; „ ... 
6 
1322 
53 
27^ 
26 
L.G. 
.. „ 1*648; o ... 
6 
1273 
49 
28 
31 
%-inch Gun } Smooth-bore. 
o . 
02 
S Hd 
X> Pi 
ts +3 
N O 
Pressure by 
crusher gauge at 
180 lb. Shot. 
58 
S £ 
A. 
B. 
C. 
f.s. 
tons. 
tons. 
tons. 
E.L.G....density, 1*675; 30lbs, .. 
4 
1374 
294 
24£ 
21 
L.G. // 1*648; « .. 
4 
1319 
28 
224 
204 
69 lb. Shot. 
E.L.G....density, 1-675; 16 lbs. 
3 
1705 
19 
12 
24 
n n 1*732; n . 
3 
1658 
16| 
11 
16 
L.G. h 1*648; n ......... 
3 
1686 
15 
9f 
m 
// u 1*637; „ . 
3 
1679 
12 
11 
17| 
