The outer door was unlocked. Billy threw it open and burst into the well-lighted study.
"Cheer-o, pater!" he exclaimed. "Sorry I'm late. Some night, eh, what?"
CHAPTER X
THE SEAPLANE'S QUEST
"S' LONG, you festive blighters! Good luck!"
With this typically airman's farewell ringing in his ears Flight-lieutenant John Fuller, D.S.O., clambered lightly into the pilot's seat of Seaplane 445B.
Owing to Billy Barcroft's absence on leave a change round had been effected in the composition of the crews of the seaplane carrier "Hippodrome's" little nest of hornets, and as a result Fuller found himself in company with Bobby Kirkwood as his observer.
It was the night of the Barborough raid. The "Hippodrome," bound for the Firth of Forth, had picked up a wireless when some where off the Yorkshire coast, reporting the presence of four Zeppelins. Aeroplanes and seaplanes attached to the north-eastern bases had already ascended in the hope of cutting off the returning air-pirates, and in conjunction with these operations the "Hippodrome" was about to send out her airmen to grapple with the enemy in the darkness.
It was indeed a formidable and hazardous undertaking. The returning Zeppelins would certainly take advantage of the stiff westerly breeze. By keeping to a great altitude and shutting off their engines they drift, silent and unseen, over the East Coast, until it is deemed advisable to restart the motors. Even the disadvantage caused by the immense bulk of the vulnerable envelope would be discounted by its invisibility in the darkness of the night.
The Zeppelins could keep "afloat" by the buoyancy of their hydrogen-charged ballonets; the aeroplanes, being heavier than air, could not, except for a comparatively brief vol-plane, without the aid of their propellers, The roar of the latter would betray their presence to the watchers on the silent airship.
Altogether the seaplane's task savoured of a wild goose chase, only by a pure fluke might one of the aeroplanes "spot" one of the returning raiders, but on the remote chance of being able to do so the "Hippodrome's" aerial flotilla set out on its hazardous flight.
For three-quarters of an hour No 445B flew to and fro parallel to the coast. It was bitterly cold. At a minimum height of five thousand feet was a vast bank of clouds that drifted steadily eastwards.
Occasionally Kirkwood took down a wireless report from the parent ship and handed it to the pilot. Hardly a word was spoken. The voice tube was resorted to only once in that forty-five minutes.
"I'm going further out," announced Fuller. "We'll clear that patch of clouds."
With her motors purring rhythmically and the pistons throbbing in perfect tune the seaplane swung round and settled in an easterly direction, the while climbing steadily. Behind her was the tail end of a nimbus; above, through a vast rift the stars twinkled in the cold sky; beneath, thousands of feet down, was the sea, its vicious, steep waves invisible in the kindly darkness.
Suddenly, from the enshrouding masses of cloud, a dark, symmetrically elongated shape shot rapidly into the starlight. It was a Zeppelin in full flight. Columns of smoke were issuing from her exhausts, but the throb of the seaplane's motors drowned the drone of her powerful engines.
"Good!" ejaculated Fuller, actuating the rudder bar with his feet and elevating the ailerons. "That's our bird. If they don't spot us before they gain that bank of clouds, she's ours."
Eagerly yet methodically Kirkwood brought the Lewis gun ready for action. It was to be the last resource in attack, to be used only if the seaplane failed to gain the aerial "weathergage"—a superior altitude to that of her bulky antagonist.
For the present the odds were level as regards speed. The seaplane's greater rate of flight was counterbalanced by the fact that she had to climb in order to get above her intended prey and drop a bomb upon the immense and fragile bulk of the Zeppelin's envelope.
And Fuller was achieving his object. Already Seaplane 445B was passing diagonally upwards through the raider's smoking trail, the oil tinged vapour from her exhaust pipes. Every moment tended to bring the protruding stern portion of the Zep, betwixt her crew and the steadily climbing aeroplane, thus diminishing the risk of detection.
Fuller was about to check the upward climb and overhaul his antagonist when the Zeppelin appeared almost to stand on end. The whole of her upper surface was exposed to the British airmen's view. Then, almost simultaneously the seaplane seemed to be following.
It was a form of optical delusion. She was still climbing steadily. The Zeppelin had spotted her small and dangerous foe. Dropping a quantity of ballast en bloc the airship shot vertically upward to a terrific height. It was this motion that had given Fuller the impression that the seaplane was dropping.
"She's twigged us!" he shouted through the voice tube. "Let her have it."
The A.P. promptly began to let loose a whole drum of ammunition. The Zeppelin was instantly enveloped in a cloud of smoke. Into the pall of vapour the Lewis gun pumped its nickel missiles, yet no crippled flaming fabric crashed helplessly to the surface of the sea.
The smoke was a "blind." Fuller realised that. Screening herself by the dense vapour the Zeppelin had ascended almost vertically until safe from observation in the dense clouds overhead.
"Missed her, by Jove!" ejaculated the flight-lieutenant.
"More than she did us," replied Kirkwood coolly, in spite of his keen disappointment, for a small-calibre bullet had ripped the ear-pad of his airman's helmet. Whether his ear was hit he knew not. The intense cold had numbed all sense of feeling. The shot was evidently from a Maxim and one of many, but in the darkness it was impossible to see whether the seaplane had sustained any damage. Judging by her behaviour Kirkwood thought not.
Yet Fuller was loath to discontinue the chase. On and on he flew, further and further away from the "Hippodrome" and the shores of Britain, vainly hoping to pick up his quarry when the Zeppelin again emerged from the cloud banks.
"I'll swear she's shut off power and is floating somewhere in that cloud," he soliloquised. "Well, I'll have a shot at it, even if we charge smack into the brute."
With this desperate yet praiseworthy resolution the flight-lieutenant swung his frail command about and began to climb steadily towards the mass of dark clouds. Ten minutes later the seaplane entered the lower edge of the nimbus. It was like tearing through a dense fog. All sense of direction was lost. Whether the machine was climbing, banking or descending was a matter of conjecture, since the darkness and the moisture made it impossible to consult the aeronautical instrument. Ahead was nothing but an opaque curtain of mist. On either side the tips of the planes merged into invisibility. Only astern were there any light-sparks from the hot exhaust throwing a faint, ruddy glare upon the wisps of trailing vapour that followed, circling and writhing, in the wake of the swiftly-moving machine.
"If the Huns are anywhere in this stuff they'll get in a rare funk even if we don't run across them," thought Fuller, Unmindful of the danger of his own seeking he mentally pictured the panic-stricken condition of the raider, as hearing the roar of the seaplane's motors and unable to locate its position, they were in momentary peril of being rammed by an object tearing at ninety miles an hour through an optically impenetrable darkness.
Kirkwood, too, realised the risk. With nerves a-tingle he awaited developments. Faith in Fuller's prowess gave him confidence. With one hand resting lightly on the lever operating the bomb-dropping gear he waited, ready at the first signal to release the missiles of annihilation.
Suddenly the muffled roar of the exhaust gave place to a series of rapid explosions. Instinctively Kirkwood likened it to a boy rasping a stick along a row of iron palings. At the same time a succession of spurts of flame streaked overhead. The seaplane had only just scraped the underside of her antagonist. The upper planes had missed the Zeppelin's 'midship gondola by inches, and the flashes he had seen were from the airship's machine-gun as the Huns blazed furiously and erratically at their unseen but unpleasantly audible foe.