CAPTAIN NOBLE AND ME. E. A. ABEL ON EIEED GUNPOWDER, 
139 
A portion of the deposit, whitish on the surface, dark grey next the cylinder, was 
collected and sealed in separate test-tubes. 
A tin cylinder was substituted for copper, to measure the crush in this experiment. 
a. 
•1973 
A. 
■1667 
a. 
•0833 
Crush, tin 
cylinder. 
•165 
Pressure per 
square inch. 
2-67 tons. 
Experiment 4, May 10, 1871. — 4411 grs. (285’5 grms.) of R. L. G. powder were fired 
in cylinder No. 7. Gases were collected, commencing seven minutes after explosion. 
On opening the cylinder the solid products were found in a mass at the bottom ; 
and the sides of the cylinder were also as noted in the last experiment. 
The residue, however, was of intense hardness, and the difficulty of removing it was 
very great. Hardly any could be got off in lumps, but it flew off like sand before the 
chisel. 
Copper firing-wire fused off and dropped in the form of a button. 
•2963 
A. 
•1677 
•0833 
Crush, copper 
cylinder. 
•033 
Pressure per 
square inch. 
6-4 tons. 
Experiment 5, June 22, 1871. — Cylinder No. 6 calibrated and found to contain 
15,859 grs. P. powder. Fired 1586 grs. (102-77 grms.) P; but, owing to the low pressure, 
the cylinder did not become closed up very tightly and most of the gas slowly escaped. 
Solid products at the bottom and easily removed. Colour light grey on surface, dark 
grey next steel, shading into light grey near the surface. 
a. 
•1064 
A. 
•1667 
•0833 
Crush, tin 
cylinder. 
•042 
Pressure per 
square inch. 
T39 ton. 
Experiment 6, June 28, 1871. — Fired 1586 grs. (102-77 grms.) pebble in same 
cylinder (No. 6) as that used in the last experiment. Nearly all the gas escaped from 
the same cause (defect of pressure). Products of combustion not collected. 
•1064 
A. 
•1667 
•0833 
Crush, tin 
cylinder. 
•032 
Pressure 
in tons. 
1-26 
Experiment 7, June 28, 1871. — Fired 3150 grs. (204T2 grms.) pebble powder in 
cylinder No. 6. Gas collected immediately. Solid products at bottom as usual, and 
tolerably easily detached. Colour whitish grey on the smooth surface, almost black 
next steel. Fracture yellowish green with splotches of grey. . 
1 . 
•2114 
A. 
•1667 
•0833 
Crush, tin 
cylinder. 
•188 
Pressure 
in tons. 
2-93 
