CAPTAIN NOBLE AND ME, F. A. ABEL ON FIEED GTJNPOWDEE. 
143 
Experiment 20, August 28, 1872. — Fired, in cylinder No. 6, 7930 grs. (513-86 grms.) 
F. G. Cylinder was absolutely tight. Gas collected in the usual manner. On opening 
the cylinder and removing the firing-plug, observed that the little button of residue 
adhering to the firing-plug, "when cut into, had a large well-defined crystalline structure, 
the crystals being transparent although the surface of the button was dark grey. Sealed 
a portion in a tube for examination. 
Kesidue in mass at bottom of cylinder as usual ; next to nothing on sides. Colour 
and fracture much the same as in the last experiment, but the centre much lighter grey. 
Crush, copper Pressure 
cylinder. in tons. 
■0834 '-145 15-8 
Experiments 21 to 24. — These experiments discarded. 
N.B. From Experiment 16 inclusive, the crusher-gauge was put loose in the charge 
of powder to be fired ; but it having been found that the crusher-gauge was heated to 
such an extent as to soften the copper cylinder and thereby affect the observations, these 
experiments were repeated, as far as regards the pressure determinations, in experiments 
25 to 32. 
2. A. 
•5322 T667 
(This pressure rejected.) 
Experiment 25, October 1, 1872. — Fired 2974 grs. (192-72 grms.) F. G. in cylinder 
No. 7. 
s A Crush, copper Pressure 
cylinder. in tons. 
•3860 -0834 -0417 -051 7-68 
Experiment 26, October 17, 1872. — Fired 1586 grs. (102-77 grms.) F. G. in cylinder 
No. 6. 
. Crush, tin Pressure in 
cylinder. tons. 
•1064 -0834 -0417 -016 0-96 
Experiment 27, October 18, 1872. — Fired 3172 grs. (205-55 grms.) F. G. in cylinder 
No. 6. 
2 . 
•2129 
A. 
•0834 
a Crush, copper 
cylinder. 
•0417 -008 
Pressure 
in tons. 
3-0 
Experiment 28, October 18, 1872. — Fired 4758 grs. (308-32 grms.) F. G. in cylinder 
No. 6. 
s A rush, copper Pressure 
o. A. a. v -i r • , 
cylinder. in tons. 
•3193 -0834 -0417 -032 6-32 
