92 
MINUTES OE PIIOCEEDINGS OF 
It was at this time that the author was appointed Assistant Superintendent 
in succession to Captain Smith; and, being impregnated with the then 
currently accepted theory that the rate of combustion of the charge depended 
mainly on the amount of surface of powder under combustion, he suggested 
to Colonel Younghusband that probably the fact that Mr. Pigou's sample 
consisted of irregularly shaped grains was the reason why he obtained a better 
velocity than could be obtained with the Waltham Abbey regular cubes, 
because the irregularly shaped grains would present larger surfaces for initial 
ignition. It would not do to use small grains, because they would interfere 
with the passage of the flame in igniting the charge; but there could be no 
objection to large irregularly shaped grains. Colonel Younghusband tried 
the experiment, and used the larger rollers in an ordinary granulating machine 
to break up press-cake into irregular grains. This was mixed with knife-cut 
pebbles, and, on firing a sample of the ordinary work in comparison, the 
following result was obtained :— 
Storing. 
Density. 
Experiment. 
m.y. 
Pressures. 
Date. 
No. 
A. 
P. 
C. 
25. 4. 71 
1*770 
2. 5. 71 
483 
1399 
1G-9 
, 16*6 
15*6 
25. 4. 717 
Granl.P. ) 
1 
2. 5. 71 
1 
485 
1436 
^ 19*4 
19-3 
19*7 j 
It seemed to the author that, in Colonel Younghusband’s machine, the 
strips might be made to rectify themselves by being allowed, in the first 
instance, to drop on a canvas band which, as it travelled, would convey each 
strip forward so as to allow the next to drop behind it, and afterwards con¬ 
vey the strips in succession in the proper position to pass through the second 
pair of rollers as follows 
Fig. 5. Scale aV 
This plan was tried, and was found to answer quite successfully. A very 
simple machine thus constructed was in operation from the end of May 1871 
to March 1872. The following is the proof of the first sample turned out 
by this machine 
Storing. 
Density. 
Experiment. 
M. V. 
Pressures. 
Date. 
| No. 
A. 
B. \ 
C. 
19. 5. 71 
1*768 
24. 5. 71 
1 534 
1475 
20*9 
203 1 
200 
