ne attempts to come to
the surface and use the rapid-fire gun with which she is armed she is at
a disadvantage, because it takes her several minutes to emerge.
Additional time is required to swing the gun up through its automatic
hatch while the men scramble to the deck to man it.

The chaser, with a speed of approximately 35 to 40 miles an hour, will
travel somewhere between a mile and a half to two miles in this period.
Its gun has been ready from the start, and the chaser has had half a
dozen shots or so with only a single hit needed to put the submarine out
of commission. Even if the submarine is at the surface and has her gun
mounted ready for action, she is at a disadvantage with the chaser. The
chaser, taking advantage of her speed and small size, goes skimming
across the water at the rate of 40 miles an hour, and it takes a mighty
fine gunner to be able to hit a small craft, going in a zigzag course
over the water at such speed.

The chaser may continue to circle the submarine awaiting her opportunity
which will of necessity come when the U-boat attempts to submerge. The
submarine must go through the regular form of running back her gun, and
battening down the water-tight hatches, before she can submerge, and the
latter process again takes several minutes. Therefore while the
submarine is preparing to dip, the chaser can run upon her and let loose
the fire from its rapid-fire gun.

A POOR SURFACE FIGHTER.

The submarine, by very virtue of the qualities which make it a good
submarine, is a poor boat for surface fighting. It can carry no very
heavy armament, and it is not heavily armored. The problem of stowing
away all the heavy machinery, supplies, torpedoes and devices necessary
for her operations and maneuvering has presented about all the
difficulties the constructors have been able to handle. The highest
speed of the submarine is not in excess of 20 miles an hour. The
submarine must be light and easy to handle. It gains in steadiness and
certainty of operation with increased size, but it loses in capacity for
quick and delicate maneuvering.

In addition the submarine has what is termed a strategic vulnerability.
A shot which might mean nothing more serious than a hole in the side to
a surface boat would end the submarine's usefulness for underseas work
and convert her into a helpless hulk of surface craft.

The submarine is an easy quarry for a chaser, for even when submerged
and moving along, the U