From Aubyn's point of view the forthcoming operations were entirely new. For the first time in his experience he was to take part in an action between ships and shore batteries, the latter being both fixed and mobile. It was a comparatively easy matter to plant shells into forts the position of which were known, but the Germans had brought up heavy guns mounted on travelling platforms, which could be moved with considerable celerity behind the long, low-lying sand dunes between Nieuport and Zeebrugge.
It was partly to locate the latter that the airmen had preceded the bombarding ships, and also to harass the enemy's lines of communication. Moreover, hostile submarines were reported to have been brought in sections to Zeebrugge, where they were being bolted together ready to take the offensive against the British vessels operating off the Belgian coast.
The "Sunderland," like her consorts, was already cleared for action. All the crew were behind the protected portions of the ship, but the captain and seven of the officers elected to fight the ship not from the armoured conning-tower but from the fore-bridge.
"By Jove! They're at it already," exclaimed Oswestry, as a series of rapid detonations came from across the dunes.
By the aid of their glasses the officers could discern the fleecy mushrooms of smoke caused by the bursting of the anti-aerial guns directed against the British airmen. Viewed from a distance it seemed impossible that a frail aeroplane could exist amid that tornado of shell.
"Wireless reports mobile battery three hundred yards sou'-sou'-east of Clemskercke church, sir," reported a signalman.
Promptly the news was transmitted to the fire-control platform. In his lofty perch a gunnery-lieutenant was busy with a complication of instruments, assisted by a midshipman and three seamen.
"Fire-control to for'ard 6-inch gun: stand by!" came the telephonic order. "Fire-control to port battery stand by."
Round swung the guns, "laid" by the master hand of the gunnery-lieutenant on the fire-control platform. Docilely obedient to the delicate mechanism they reared their muzzles high in the air.
Then, with a crash that shook the ship, five of the 6-inch guns spoke simultaneously. To the accompaniment of a long-drawn shriek the 100-pound missiles hurtled through space.