294 
MINUTES OF PROCEEDINGS OF 
Two slots are cut in the top of the body to serve as key holes. The “ key 
iron, fuze and plug general service ” is used with these fuzes. 
In other respects the construction of the general service fuze is similar to 
that of Pettman’s sea service fuze, the arrangements which have been adopted 
in the latter fuze for bringing the sensitiveness of the fuze within the exact 
limits prescribed for naval service* * * § being embodied in the general service 
fuze. The fuze has thus the enlarged chamber and the copper disc over the 
ball,f it has also the solid base with fire hole closed with a cardboard disc, and 
the groove round the lower part of the body for the lead cup to expand into 
and fix itself. 
The general service fuze is stamped on the top with the numeral, number 
of thousand, and month and year of issue. 
Action .—The action of this fuze fixed in a spherical shell is under all 
circumstances the same as that of the other Pettman fuzes, except that the 
shock of discharge has to shear the suspending wire instead of merely 
crushing a lead cup. 
But under the condition which may arise in a B.L. rifle shell,} of the 
detonating ball not becoming disengaged from its supports, the special 
arrangement in the head of the fuze becomes indispensable to its action. 
Under these circumstances what happens is as follows :—The plain ball 
having by the descent of the steady plug on the shock of discharge been 
thrown out of its cup supports, it occupies during the flight of the shell a 
position between the top and steady plugs immediately over the detonating 
composition of the latter. On the impact of the shell end on, the steady 
plug is thrown violently forward against the plain ball, the blow sufficing to 
explode the detonating composition in the plug, the flash from which passes 
through the fire holes in the steady plug to the detonating ball or directly to 
the cone plug. § 
The general service fuze is intended for use with all naval spherical shell 
and all M.L. or B.L. rifle shell having the general service fuze hole or 
adapter, and when a sufficient number of fuzes and adapters are made it will 
entirely supersede the sea service Pettman’s fuze. || 
* For a definition of those limits, see p. 80. 
f The ball is the same as that of the other Pettman fuzes. In manufacture somewhat closer 
limits are observed, the limits of weight of the uncovered ball being 130 to 140 grains, instead of 
from 125 to 140 grs. as laid down for the other fuzes. The weight of the ball covered is the same 
as that of the sea service fuze, viz. from 148 to 160 grains. 
J Vide p. 82. In those B.L. shells in which a lateral concussion does take place the condition 
defined in the text could not arise. 
§ Action will ensue whether the detonating ball be ignited by the flash from the steady plug or 
not. The inclined fire holes in the cone plug by providing a passage for the latter makes the ignition 
altogether independent of the detonating ball. 
|| See on the subject of the introduction of the fuze and the gradual supersession of the S.S. fuze. 
W.O. Letter, 5th July, 1866, Jl- 
