The times., 1898-05-17

DOal- <hS tliiS HUTk ReUeIdliy Id doiS AZ
full view and range of the enemy, 1t Is
designed to be done as automatically as
possible, SO that neither nervousness nor
casualties may interfere with Its sue
cessful operation.
Accordingly the steamboat towing the
launch proceeds at its full speed, being
steered on a prearranged bearing. AS
soon as the mine field that is to be at
tackled is reached buoy attached to the
end of a cable is thrown overheard, while
the boats rush on. The countermines
have been hung along the thwarts OF the
launch and are arranged so that when
a certain tension is put upon their fasten-
| ings they are released automatically and
are allowed to drop into the sea. When
| the entire line has gone overheard the
| towing steamer hoists a red flag, or IL at
night, fires a rocket.
This is the signal for the firing bat
| teries at the two ends of the cable TO be
| joined. A second and similar signal IN
dicates the pressing of the firing Key py
| an officer on the steamer, and the conse-
| quent explosion of the line of counter
mines. Almose invariably it is found that
| the force of the explosion has been sufii-
| cient to break the connections OF the
| enemy's line of mines. This automatic
principle of countermining shows its chief
| usefulness in the fact that no one need
1 be on board thel.launch.
Sweeping" is perhaps the most unre-
liable method known of clearing mine
| field, but if it is carried out carefully Is
frequently effective. When the Federal
| fleet during the civil war sailed into
Mobile Bay 1t was found that the harbor
and river was planted so thickly with I'M
provised mines and torpedoes that the
safety of the ships in the attacking squad
ron were menaced. An attempt was made
| to remove them by ordinary means, but
l 4. It.1 Il Ion af CD in
employed in the work. The method of
countermining was well enough known at
| that time, but the unreliability of electri-
| cal firing devices in those days was such
| that all attempts to operate q line OF
| countermines failed In despair of fore
ing the defenses of the harbor the Gov
| ernment sent to New York for Capt. z.
r. Love- an experienced diver.
Capt Lowe tried for some time to re-
move the mines and torpedoes by means
| of his divers, but failing 10 accomplish
| the work he was reduced to the neces-
| sity of dragging the bottom of the har-
Dor with a hawser of steel wire. The tor
| pedoes were pulled from their moorings,
and although two tug boats were blown
up in the efforts, the harbor was cleared
so that Federal ships We're able TO at
tack the fort with comparative ease.
| This experience showed the Government
| that while divers were often of great
usse in placing mines they were OF no
| value at all in removing them.
Two or more boats are employed in the
manipulation of a sweep" Several kinds
of Sweeps are used in the service,
ranging from the wire cable used by
! Capt. Lowe to an arrangement which is
practically a small counter mine. The
| one generally used in the United States
| Navy is composed of about twenty faith
oms of two-inch rope or wire cable, with
.t.,, ooh afl1 md
fitted with arms 10 catch the mooring
| ropes of mines. 1t is suspended by lines
from three floats or buoys attached at
| the center and ends. The boats selected
for the manipulation of a sweep are gen
! orally those drawing the least possible
amount of water, so as to reduce the pos
| siblility of their colliding with mine TO
a minimum. Each boat carries an cleo
trical firing battery.
/ When the boats arrive al the passage
| which il is intended to sweep clear of
| mines each boat takes an end of the cable
| and, separating, proceeds to drag IL be-
| hind them. As soon as resistance is felt
the boats gradually approach one an
! other and the position of the obstruction
| is determined. This having been done.
| the line is pulled so as to bring the near
| est charge OF gun cotton in contact with
the mine, and the gun cotton is discharg-
| ed. This process is repeated until the
| CndDnel Is considered CledT OF UlltSr
| when it is swept once more 10 make sure
| that none has been missed.
Creeping is considered the most eff
| cacious method of destroying mines, as
| il Is directed solely against the cable con-
! Meeting the mine cable with the shore
batteries. Once this IS destroyed or cut
! the mines are considered harmless. Two
"creeps' are used by our Navy. One
| is a sort Of explosive grapnel, consisting
| of a charge Of three pounds of gun cot
| ton surrounded by three large hooks
| turned outward the other Is simply an
ordinary grapneL used for fishing up the
cable when it is encountered.
In use one or both of these grapnels is
| dragged behind the boat which is doing
the ''creepng." When an obstruction is
| encountered the operator on the boat
| pulls the grapnel line taut and fires the
| charge attached to the hook. This usu-
| ally destroys the shore connection. In us
| ing the non-explosive gTapnel the cable
| IS caught and pulled up to the boat Then
| 1t is cut, battery attached and the en-
| tire field of mines is exploded harmlessly
| from the boat.
Although creeping cannot be carried
| on with any degree of success on rocky
bottom it is the method usually adopted
| in warfare. When whole mine fields have
| TO be cleared countermining is the prefer
| able method, but 1t is practically hope
| less under the fire batteres on shore. The
| tactics taught in the United States Navy
| are that when circumstances are so ur-
gent that a passage must be forced
| through a mine field at once and at all
| hazards the best course is for the ships
to follow in single column six cables
apart, the least valuable vessels leading
| The small ships can tow drags or sweeps.
| They almost assuredly will be sunk by
| the mines, but they will have cleared the
F, battleships which follow.