EXPLOSIVES—0O’HERN. 
ing body resists any force tending to change 
the direction of its axis of rotation. To imsure 
the torpedo’s following a desired direction, it 
is only necessary then to point the axis of the 
gyroscope in the proper direction before launch- 
ing the torpedo. The size and effective range 
of torpedoes have been greatly increased within 
recent years. Those of late construction are as 
much as 21 inches in diameter, 16 feet long, 
have an extreme range of at least 10,000 yards, 
or nearly 6 miles, a maximum speed of at least 
36 miles per hour, and carry a charge of as 
much as 300 pounds of high explosive. 
EXPLOSIVES USED. 
Until recently, dynamite and guncotton have 
been the principal explosives used in submarine 
warfare, but there is reason to believe that some 
of the important countries have adopted for 
that purpose the explosive trinitrotoluol or 
other similar explosives. Dynamite has the 
advantage of cheapness and ease of ignition. 
Its disadvantages are changing sensibility when 
freezing and thawing, and separation of the 
nitroglycerin from the absorbent if the dyna- 
mite becomes wet through leakage in the mine 
case. Guncotton has usually been employed 
wet, in which condition it is safe and insensi- 
tive, but can be detonated only by means of a 
priming charge of dry guncotton. The chief 
objection to guncotton is the danger in handling 
the dry primer, and its liability to become 
accidentally wet and thereby prevent the func- 
tioning of the mine. Trinitrotoluol has the 
advantage of being safe to handle and of not 
being affected by contact with water. 
ISOLATION OF MAGAZINES. 
There is no general law in this country pre- 
scribing requirements as to the character of 
magazines for storing explosives, nor as to the 
location of storage places with respect to 
dwellings, although there are usually State 
73176°—sm 1914——18 
SUWELLLIND 
AMVMNG FW. 
DLT VY (7M. 
Fia. 9.—Self-propelling submarine torpedo. 
