VII.

FUSE - SAFETY, INSTANTANEOUS, & DETONATING:

A.

Safety Fuse:

1.

Fuse, Safety, No. 11, Mks I & II:

This fuse consists of a column of fine gunpowder enclosed in a Jute yarn cover-ed with a bitumen coating protected by a varnished black tape, the whole having a diameter of about .21 inches. It burns at about 2 ft. per second and will function under water.

B.

Instantaneous Fuse:

1.

Fuse, Instantaneous, Mk. III:

This is not a detonating fuse, but it can be ignited by safety fuse or flame, and burns at not less than 90 ft. per second. It is enclosed in an orange clored tape binding.

2.

Fuse, Instantaneous, Mk. IV:

This fuse is similar to the Mk. III fuse, except that it is enclosed in a red-colored water-proof tape.

C.

Detonating Fuse:

1.

Fuse, Instantaneous, Detonating, TNT, Mk. III (F.I.D.):

This fuse consists of a lead and tin alloy tube about .23 inches in diameter filled with specially prepared TNT. It detonates at a rate of about 5000 meters per se-cond.

2.

Cordeau-Bickford:

Consists of a lead tube completely and uniformly filled with TNT. Detonates at about 4,500 meters/sec.

3.

Fuse, Instantaneous, Detonating, Cordtex, Mk IV:

Consists of a core of PETN surrounded by a cellophane tape and enclosed in lay-ers of jute and cotton yarn contained in a tubular covering of waterproof composi-tion resembling aluminum in color. The external diameter is .19 inches. Detonation rate if approximately 20,000 ft/sec.

Some issues of Cordtex will be covered with rubberized tape instead of cello-phane tape. Packages containing these issues will be marked "R". Packages con-taining Cordtex covered by plastic instead of bitumen will be marked "P".