154 
CAPTAIN NOBLE AND ME. F. A. ABEL ON FIEED GUNPOWDER. 
a . Crush, copper Pressure 
' ‘ a ‘ cylinder. in tons. 
•9000 -0833 -0833 1-44 31-4 
Experiment 78, January 12, 1874. — Fired 5320 grs. (344*74 grms.) in same cylinder. 
On opening, the colour of the deposit was a lighter grey than usual. The contraction 
after setting appeared to be considerable, apparently *2 inch. 
In this experiment, before firing, a piece of the finest platinum wire *, also a piece of 
sheet platinum about 1 inch (26 millims.), square and *03 inch (’76 millim.) thick were 
placed among the powder. After the explosion the thin platinum wire had disappeared, 
but small globules of the metal were found in many places welded to the surface of the 
cylinder. 
The sheet platinum was not melted, but was doubled up ; there were appearances, 
however, of fusion on its surface, and in places the platinum wire had been welded to 
the sheet. The weight of the sheet platinum was about 0*25 oz. (about 6 grms.). 
S. A. a. Crush. Pressure in tons. 
•7 *0833 -0833 -067 18-9 
Experiment 79, January 14, 1874. — Fired 5320 grs. (344-74 grms.) Spanish pebble 
powder; put in a coil of platinum wire *06 inch (1'52 millim.) in diameter, weighing 
about 15 grms. 
The platinum after the explosion was found in a lump at the bottom of the deposit 
thoroughly fused, with the exception of a small portion. Colour and appearance of 
residue rather different from the ordinary. There were a good many light-coloured 
splotches. The surface of the deposit was broken and rough, as if by the escape of gas. 
S. - A. a. Crush. Pressure in tons. 
•700 -0833 -0833 *056 17 
Experiment 80, January 16, 1874. — Fired 5960 grs. (386-21 grms.) R. F. G. 
Quantity of gas measured . . . . 109*540 cub. centims. 
Temperature of gas 18 0, 33 C. 
Barometric pressure 729 millims. 
Experiment 81. — Fired 5960 grs. (386‘21 grms.) pebble (Spanish). 
Quantity of gas measured .... 98,607-7 cub. centims. 
Temperature of gas 16 0, 67 C. 
Barometric pressure 735 millims. 
Experiment 8 2. —Placed in a Siemens furnace, at a temperature of about 1700° C., 
two crucibles, one containing powder-residue, the other equal weights of potassium 
carbonate and liver of sulphur. On first placing them in the furnace a little ebullition 
took place, apparently in both crucibles, but with some violence in the crucible with 
powder-residue. This ebullition, however, soon subsided and a slow volatilization 
* Wound round the sheet platinum. 
