OKEHAMPTON EXPERIMENTS. 
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APPENDIX. 
Description of Projectiles used at Okehampton . 
Boxer-Shrapnel Shell .--The shrapnel shell for 16-pr. guns was that known as 
Experimental, pattern E. 
It was filled with 72 mixed metal bullets at 18 to the pound, 56 bullets at 84 
to the pound, and lj-oz. bursting charge. 
The walls of the cast-iron shell were 0*45 ins. thick, and there were no interior 
longitudinal grooves. Mean weight, 18 lbs. 6 ozs. 
The 9-pr. shrapnel shell was Mark V. pattern. 
It was filled with 68 mixed metal bullets at 18 to the pound, 35 at 34 to the 
pound, and 12 drams bursting charge. Mean weight, 9 lbs. 13 ozs. 
Common Shell .—The ordinary service common shell was used with both guns. 
16-pr. filled with 1 lb. of powder. Mean weight, 15 lb. 13 ozs. 
9-pr. filled with 7i ozs. of powder. Mean weight, 9 lb. 1 oz. 
Water Shell .—The ordinary common shell is converted into a “ water shell ” 
by filling it with water instead of gunpowder, and inserting a small gunmetal 
cylinder, containing the explosive, into the fuze-hole in addition to the E.L. 
percussion fuze. It was proposed by E. A. Abel, Esq., E.R.S., the Chemist of the 
War Department. 
In the water shells used at Okehampton, the small gunmetal cylinder was about 
2'2ins. in length, by 0‘8-in. internal diameter. It contained, in the body, three 
pellets of dry compressed gun-cotton, protected by a coating of paraffin, and weighing 
together about one-third of an ounce, called the primer. Its top was fitted with a 
removable gunmetal chamber, which contained about 20 grains of fulminating 
mercury. 
This gun-metal chamber, called the “ detonator,” can be removed and replaced 
by a solid plug, if necessary, for safety during transit or storage. 
The shell was filled as follows 
The plug was removed, and water was poured into the interior until it rose 
into the bottom of the fuze-hole. The gunmetal cylinder, containing the 
"primer ” and “detonator,” was then screwed home in the fuze-hole as 
far as it would go, the plug was then replaced. When required for use, 
the plug was removed and the R.L. percussion fuze screwed into the 
shell. 
The action of the shell is as follows 
On striking the ground, or any object, the percussion fuze acts and fires the 
fulminating mixture, which detonates the gun-cotton. The force of the. 
explosion, acting through the incompressible substance water, is then 
instantaneously and completely transmitted in all directions, and the shell 
is thus broken up into a far greater number of pieces than that obtained 
by employing the full charge of gunpowder which it can contain. 
Description of the M.L . Wood Time Fuze , Experimental\ supplied to 
Okehampton. 
The external dimensions of the 15-secs., 10-secs., and 5-secs, fuzes are the same 
us the 10-secs, and 5-secs, service fuzes, the composition bore being concentric, 
