st,
an oversea fighting seaplane, to operate from a ship as base; next, a
scouting seaplane, to work with the fleet at sea; and last, a
home-service fighting aeroplane, to repel enemy aircraft when they
attack the vulnerable points of our island, and to carry out patrol
duties along the coast. The events of the war have given historic
interest to all forecasts prepared before the war. Mr. Churchill's
minute is naturally much concerned with the Zeppelin, which should be
attacked, he says, by an aeroplane descending on it obliquely from
above, and discharging a series of small bombs or fireballs, at rapid
intervals, so that a string of them, more than a hundred yards in
length, would be drawn like a whiplash across the gas-bag. This is a
near anticipation of the method by which Flight Sub-Lieutenant R. A. J.
Warneford brought down a Zeppelin in flames between Ghent and Brussels
on the 7th of June 1915. The immense improvements in construction which
were wrought by the war may be measured by Mr. Churchill's
specifications for the rate of climb of the two-seater aeroplanes and
seaplanes--namely, three thousand feet in twenty minutes. When he
drafted his scheme that was a good rate of climb; before the war ended
there were machines on the flying fronts which could climb three
thousand feet in two minutes.

Under the direction of the Air Department much attention was paid by
pilots in the Naval Air Service to experimental work and the diverse
uses of aeroplanes. So early as January 1912 Lieutenant H. A.
Williamson, R.N., a submarine officer who had gained the Royal Aero Club
certificate, submitted to the Admiralty a paper which anticipated some
later successes. He advocated the use of aeroplanes operating from a
parent ship for the detection of submarines, and showed how bombs
exploding twenty feet below the surface might be used to destroy these
craft. The practical introduction of depth charges was delayed for years
by the difficulty of devising the delicate and accurate mechanism which
uses the pressure of the water to explode the bomb at a given depth. But
before the war ended the detection of submarines from the air and the
use by surface craft of depth charges for destroying them had been
brought to such a degree of efficiency that the submarine menace was
countered and held. The submarine learned to fear aircraft as the birds
of the thicket fear the hawk. It would be tedious to attempt to describe
the long series of e