arines sped out to sea to
attack the British ships. The mist, which grew thicker, turned the
combat from a battle into a mere disorderly raid, but out of it the
seaplanes emerged unhurt. All made their way safely back to the
fleet, after having dropped their bombs with a degree of damage
never precisely known. The weakness of the seaplane is that on
returning to its parent ship it cannot usually alight upon her deck,
even though a landing platform has been provided. It must, as a
rule, drop to the surface of the ocean, and if this be at all rough
the machine very speedily goes to pieces. This was the case with
four of the seven seaplanes which took part in the raid on Cuxhaven.
All however delivered their pilots safely to the awaiting fleet and
none fell a victim to the German anti-aircraft guns.

In May of 1917, the British Royal Naval Air Service undertook the
mapping of the coast of Belgium north from Nieuport, the most
northerly seaport held by the British, to the southern boundary of
Holland. This section of coast was held by the Germans and in it
were included the two submarine bases of Zeebrugge and Ostend. At
the latter point the long line of German trenches extending to the
boundary of Switzerland rested its right flank on the sea. The whole
coast north of that was lined with German batteries, snugly
concealed in the rolling sand dunes and masked by the waving grasses
of a barren coast. From British ships thirty miles out at sea, for
the waters there are shallow and large vessels can only at great
peril approach the shore, the seaplanes were launched. Just south of
Nieuport a land base was established as a rendezvous for both
air-and seaplanes when their day's work was done. From fleet and
station the aerial observers took their way daily to the enemy's
coast. Every mile of it was photographed. The hidden batteries were
detected and the inexorable record of their presence imprinted on
the films. The work in progress at Ostend and Zeebrugge, the active
construction of basins, locks, and quays, the progress of the great
mole building at the latter port, the activities of submarines and
destroyers within the harbour, the locations of guns and the
positions of barracks were all indelibly set down. These films
developed at leisure were made into coherent wholes, placed in
projecting machines, and displayed like moving pictures in the ward
rooms of the ships hovering off shore, so that the naval forces
preparing fo