ork of the airship during the war,
and, like everything else, underwent most striking changes. Submarine
hunting probably had more clever brains concentrated upon it than
anything else in the war, and the part allotted to the airship in
conjunction with the hunting flotillas of surface craft was carefully
thought out.

In the case of a suspected submarine in a certain spot, all surface and
air craft were concentrated by means of wireless signals at the
appointed rendezvous. It is in operations of this kind that the
airship is so superior to the seaplane or aeroplane, as she can hover
over a fixed point for an indefinite period with engines shut off. If
the submarine was located from the air, signals were given and depth
charges dropped in the position pointed out. Incidents of this kind
were of frequent occurrence, and in them the value of the airship was
fully recognized.

The most monotonous and arduous of the airship's duties was the routine
patrol. The ship would leave her shed before dawn and be at the
appointed place many miles away from land. She then would carry out
patrol, closely scanning the sea all round, and investigating any
suspicious object. For hours this might last with nothing seen, and
then in the gathering darkness the ship would make her way home often
against a rising wind, and in the winter through hail and snow. Bombs
were always carried, and on many occasions direct hits were observed on
enemy submarines. A sharp look-out was always kept for mines, and many
were destroyed, either by gunfire from the airship herself or through
the agency of patrol boats in the vicinity. This was the chief work of
the S.S. ships, and was brought to a high pitch of perfection by the
S.S. Zero. These ships proved so handy that they could circle round an
object without ever losing sight of it, and yet could be taken in and
out of sheds in weather too bad to handle bigger ships.

The hunting of the submarine has been likened to big-game hunting, and
certainly no one ever set out to destroy a bigger quarry. It needs the
same amount of patience and the same vigilance. Days may pass without
the opportunity, and that will only be a fleeting one: the
psychological moment must be seized and it will not brook a moment's
delay. The eye must be trained to pick up the minutest detail, and
must be capable of doing this for hour after hour. For those on
submarine patrol in a small ship there is not one second's