SERVICE FUSE

No. 11 Safety or Time Fuse

Description. Color, black. Smooth surface.

Time of Burning. One foot in thirty seconds.

Composition. Train of slow match inside a wrapping of hemp or flax, covered by layer of gutta-percha, surrounded by binding of black waterproof tape.

INSTANTANEOUS OR QUICK FUSE

Color, red. Ribbed surface.

Time of Burning. Eighty feet per second.

Composition. Same as service fuse, except that it contains quick match in place of slow match.

Caution. Instantaneous fuse must never be stored alongside safety fuse.

DETONATORS

SERVICE

No. 8 Mark VII

Description. Copper tube open at one end painted red, marked on white label, No. 8. M.K. VII containing 32 grs. fulminate of mercury.

COMMERCIAL (Long)

COMMERCIAL (Short)

Description. Copper tube, open one end, containing 25 grs. fulminate of mercury.

EXPLODERS

SERVICE

Guncotton. One-oz. primer, 15-oz. slab. See Explosives, Guncotton.

No. 2 Detonator for Hand Grenade. Consists of brass tube (detonator holder) with flat screw head. The other end is fitted with a cavity which carries N.G. percussion cap. A commercial detonator open end toward the screw head is placed inside, its open end closed with a wooden plug; the closed end is pierced with four flash holes to enable flash from percussion cap to communicate with F. of M. in detonator. A brass screw in head of detonator holder closes detonator tube.

This detonator has three screw threads.

No. 3 Detonator. See description of No. 2. This detonator is ¼ in. longer than No. 2, and has two screw threads.

PATENT LIGHTERS

Nobel Lighter. (See Plates 8 and 9.) The lighter is made up of two cardboard tubes, one fitting over the other; inside the end of the larger tube is a small brass cap containing friction composition. At the top of the smaller tube are two friction points. These points are held about ¼ in. from the cap containing friction composition, by a safety pin passing through both tubes. At the other end of the smaller tube is a small copper band into which the fuse can be crimped. A narrow band of waterproof tape with a loose end is glued around the joint of the two tubes to keep out moisture.

To Assemble. Insert fuse into lighter, fasten by crimping, and insert other end of fuse into detonator. The joints at lighter and detonator should be waxed to make it damp-proof and flash-proof.

Brock Lighter. See Grenade Hand. Consists of a small cardboard cup filled with friction composition, covered with waterproof paper. The latter can be torn off by pulling a small tag which is left free.

Grenades with fuses are so arranged (with sufficient length of fuse) to explode from 3 to 5 seconds after being ignited and thrown, giving the thrower plenty of time (when throwing from a trench) to bend down safe. Grenades, without fuses (but with detonators only) will explode on impact; for instance, in Grenade No. 1, Mark I, it is obvious when instructions (see p. 2, Grenade 1) are carried out, and grenade is thrown, that the steel needle will be driven into the detonator and exploded.

In Grenade No. 3, Mark I, when safety pin is removed and releasing socket slipped back, the wind vane revolves backward (during the passage through the air) until far enough to allow the retaining bolt to fall out. This leaves nothing between the firing needle and detonator cap except a very thin spiral spring which is only strong enough to hold the weight of the needle pellet until the shock of impact when the grenade explodes.

In Grenade No. 20 releasing collar slips back on the rifle being fired.

In Grenade No. 5, Mark I. On this grenade being thrown the pressure of the fingers being released the striking lever flies outward by the pressure of the powerful spring, releasing the shoulder of the firing striker which is driven on to the fuse and explodes in 4½ seconds.

All other grenades, see pages opposite plates.

---