beneath.

The use of this fuse involves the curious question of the physical
conditions now existing in the discharge of our projectiles by slow burning
powder. The forward movement of the shell is now so gradual that the
inertia of a pellet is only sufficient to shear a wire of one-tenth the
strength of that which might formerly have been sheared by a similar pellet
in an old type gun with quick burning powder. Consequently, in many cases,
it is found better not to depend on a suspending wire thus sheared, but to
adopt direct action. The fuse in question would, we believe, act even on
graze, at any angle over 10°. Probably at less angles than 10° it would not
explode against water, which would be an advantage in firing at ships.

Shells so gently put in motion, and having no windage, might be made, it
might naturally be supposed, singularly thin, and the adoption of steel in
place of iron calls for some explanation. The reason is that it has been
found that common shells break up against masonry, instead of penetrating
it, when fired from these large high velocity guns.

The shrapnel shell is shown at Fig. 5. Like the common shell, it is made of
steel, and is of the general form of the pattern of General Boxer, with
wooden head, central tube, and bursting charge in the base. It contains
2,300 four ounce sand shots and an 8 lb. bursting charge. It weighs 1,800
lb. The fuse is time and percussion. It is shown in Figs. 6 and 6A. It
closely resembles the original Armstrong time and percussion pattern.

[Illustration: FIG. 6A.]

The action is as follows: The ignition pellet, A, which is ordinarily held
by a safety pin, is, after the withdrawal of the latter, only held by a