Fighting A Depth Bomb
: Winning A Cause World War Stories
All who have read of the sinking of the Lusitania, by a torpedo, shot
from a German U-boat, realize the terribly destructive force of this
modern weapon of war, but many do not know that the depth bomb is even
more destructive and must be handled with much greater care to be sure
that it does not explode accidentally or prematurely. The bomb usually
contains from 100 to 500 pounds of tri-nitro-toluol, or T.N.T., as it
is usually called, the most powerful of all explosives. The explosion
of a ship loaded with it in Halifax harbor, December 6, 1917, caused
almost as great a loss of life and property as a volcanic eruption.
When the 500 pounds of T.N.T. is exploded it changes suddenly into
nearly 80,000 cubic feet of gas. Now this amount of gas will fill a
room 160 feet long, 25 feet wide, and 20 feet high. When the bomb
explodes under the water the gas must find room somewhere, and with
tremendous force it pushes the water in all directions. If a hollow
submarine is near the point of the explosion, its walls will give way
easier than the water around it and it is crushed like an empty egg
Only very swift boats should drop the depth bombs from their sterns,
for the boat must be moving at a rate of at least twenty-five miles an
hour to be sure to escape damage from the bombs dropped behind her.
John Mackenzie, the hero of this story, writes in regard to the
converted yachts used for dropping depth bombs in European waters as
follows: Only destroyers made speed exceeding 25 knots. There were no
converted yachts operating in European waters capable of making 25
knots. A very few made 15 to 18 and the majority about 12. Of course
we had to take our chances in getting away safely, although we knew
that the chances were about even. That is, we were in about as much
danger from our depth charges as the enemy was. His statement shows
the risks that American sailors were willing to take.
The bomb, of course, weighs over one hundred pounds. It is made with
one end flattened, upon which it will stand, and in the early types its
accidental discharge is rendered practically impossible by a sort of
peg called a safety pin, which must be removed before the bomb is
dropped. The use of depth bombs against the U-boats made fighting in
the German submarines so dangerous and so much to be dreaded, that it
is said, as the war drew to a close, all U-boat crews had to be forced
into service, and that none of them expected ever to return and see
their homes and friends again.
In the early days of the war the bombs were carried in cradles, and
later in racks or run-ways. From most of the bombs the detonator,
which would fire them, was removed; but some were kept ready for
instant firing, near the stern of the ship. The early type of bomb was
discharged by a length of wire attached to a float. The bomb itself
sank, the float remained on the surface of the water and reeled off the
wire until the pull upon it discharged the bomb. It can be readily
seen that the depth at which the bomb was discharged would depend upon
the length of wire attached to the float. Imagine what might follow if
one of these bombs, set ready for discharge, should break loose from
its case in a storm at sea.
Such a terrible accident did happen on the U.S.S. Remlik. The ship was
groaning and tossing in a very heavy sea, for a severe storm was
raging. She gave a lurch and pitched back with so much force that a
wooden box, containing a depth bomb and securely fastened to the after
deck, suddenly broke. The bomb rolled out of the box and began to
bound back and forth across the deck as the ship lurched and pitched
from side to side.
The crew seemed stunned, and no orders were issued for concerted
action. The frightfulness of the situation was greatly increased when
it was observed that the safety pin had dropped out. All expected the
next time the bomb struck with force against the rail that the float
section would be released and reel off enough wire to fire the
detonator and utterly destroy the ship and all aboard.
But Chief Boatswain's Mate, John Mackenzie of the Naval Reserve Fleet,
needed no orders. He saw what should be done and did not wait for some
one to order him to do it. He could not pick up the bomb in his arms
and throw it overboard, for it weighed too much, and even if he could
this might be the worst thing to do. The ship was laboring and barely
holding her own with no headway, although the engines were turning over
for 8 knots, and the bomb would no doubt have exploded directly under
the ship had it gone overboard.
Mackenzie had a plan, and the first step in it was to stop the bomb.
He threw himself in front of it and tried to hold it by his arms and
the weight of his body, but the weight and the momentum of the moving
bomb were too great and he was pushed aside; but he had stopped its
movement somewhat so that when it struck the rail on the other side of
the deck it did not explode. He jumped for it as it bounded back from
the rail and almost stopped it, but it seemed to those looking on that
the hundreds of pounds of metal and explosives would roll over his body
and seriously injure him. He escaped this, however, and slowed down
the movement of the heavy bomb to such an extent that near the opposite
rail he was able to grasp it, lying with feet and hands braced in the
grating of the gun platform. Then to be sure that it did not escape
him until help came, he turned it upright upon its flattened end and
sat down upon the most destructive bomb used in war, on the deck, of a
ship lurching at sea in a severe storm.
Then other members of the crew that had been watching him as if dazed
ran to his assistance, and the bomb was soon placed in safety.
The commanding officer of the Remlik recommended that Chief
Boatswain's Mate, John Mackenzie, be awarded the Medal of Honor. The
report to the Secretary of the Navy was in part as follows:--
Mackenzie in acting as he did, exposed his life and prevented a
serious accident to the ship and the probable loss of the ship and the
entire crew. Had this depth charge exploded on the quarterdeck, with
the sea and the wind that existed at the time, there is no doubt that
the ship would have been lost.
Mackenzie was awarded by the Navy Department the Medal of Honor, and a
gratuity of one hundred dollars; but these awards are of little value
compared with the greater reward which comes to him in the admiration
and respect of all who read or hear the story of his heroic deed.