"You've been a jolly long time, you belated bird!" shouted Fuller in mock reproof. "What's the stunt?"
"Couldn't help it," replied Barcroft with a broad grin. "If you were in my place and saw a crowd of Hun Staff officers pushing along in motor-cars wouldn't your idea of courtesy lead you to pay them a little attention? Kirkwood gave 'em a couple of plums and a whole drum. Result—a slight increase in the Hun death-rate."
Barcroft had, in fact, gone well inland over the German batteries, on a sort of informal joy-ride. From a height of 5,000 feet the observer had spotted what appeared to be a motor convoy bowling along the road between Zeebrugge and Bruges. With a daring bordering on recklessness the pilot had vol-planed down to within two hundred feet, greatly to the consternation of the grey-cloaked German Staff officers, who, leaving the shelter of their steelroofed cars, scurried with loss of dignity for the safety that was denied most of them. For with admirable precision Kirkwood had dropped two bombs fairly into the line of cars, following up the attack by firing a whole drum of ammunition from the Lewis gun into the fleeing Huns.
Deftly the flexible steel wire from the outswung derrick engaged the lifting hooks of the seaplane. The machine was just clear of the water when the order came "Avast heaving." Simultaneously a bugle blared. It was the call for Flying Officers.
Leaping into the stern sheets of a boat in attendance, Barcroft and Kirkwood were taken to the side of the "Hippodrome," where they gained the deck of the ship. Already Fuller and the rest of the airmen had gone aft. Something was literally in the air.
The signal commander held up a leaf torn from a signal pad.
"A wireless has just come through," he announced in clear deliberate tones. "A hostile plane has made a raid over parts of Kent. She is now on her way back, apparently heading for Ostend. Machines from Eastchurch have started in pursuit, but the Hun has a useful lead. Now, gentlemen, a nod is as good as a wink to a blind horse: we are between the raider and his base."
The assembly dispersed like magic, the airmen hurriedly donning leather jackets and flying helmets and giving peremptory orders to the mechanics in attendance. In less than five minutes the first of the stowed seaplanes was ready to glide down the inclined platform to take to flight.
Yet, from a starting point of view Barcroft had a decided advantage. His seaplane was practically ready. There was enough petrol for a lengthy flight, and a good reserve of ammunition for the Lewis gun. Bombs there were none, nor were any likely to be required for the task in hand. The chances of a hit on a small and rapidly-moving target were very remote. It was by machine-gun fire that the attack upon the returning raider was to be made.
With the motor throbbing noisily and with clouds of oil-smelling smoke pouring from her exhaust, Barcroft's seaplane taxied away from the towering side of her ungainly parent. Then, so gracefully that it was impossible to determine the exact moment when the aircraft ceased to be waterborne, the seaplane rose swiftly and steadily in the air.
Climbing in steep spirals the machine quickly rose to a height of 5,000 feet. It was enough for all practical purposes, allowing a margin of superior altitude to that of the expected Boche.
"Good enough!" shouted the flight-sub through the speaking tube. "Aerials paid out? All ready?"
"All serene," replied Kirkwood, affixing a whole drum of ammunition to the upper side of the breech mechanism of the deadly machine gun. "By Jove, we've all been pretty slick this time. The fifth bird has just got away."
Barcroft leant over the side of the fuselage. Seven hundred feet below and speeding away to the nor'-west were a couple of the "Hippodrome's" seaplanes. Two more, at a lower altitude but still climbing, were heading in a south-easterly direction. Thus, when the formation was complete, Barcroft's machine would be in the centre of a far-flung line thrown out to form a barrier betwixt the solitary raider and his base.
The British airmen were at an atmospheric disadvantage. Straight in their face came the rays of the setting sun, while the calm sea beneath them was one blaze of reflected light. Against that blinding glare it was almost impossible to distinguish the mere black dot in the vast aerial expanse that represented the returning hostile aviator; while on the other hand the Hun, with the sun at his back, would be able to discern with comparative ease the glint of the seaplane's wings.
The characteristic tick of the wireless brought. Kirkwood to attention. With the receiver clamped to his ear he took down the message and passed it on to his companion.
"Our pigeon!" soliloquised Barcroft grimly. The information was to the effect that the "Hippodrome" had first sighted the approaching Hun machine by means of telescopes. The hostile craft had previously spotted two of the intercepting seaplanes, and her pilot, taking advantage of the light, decided to make a vol-plane to within a few hundred feet above the level of the sea. By so doing he was sacrificing his advantage of altitude, but there was a chance of slipping unobserved under the British aircraft. Once through the far-flung cordon he hoped to rely upon superior speed and climbing powers to elude pursuit.
By this time Barcroft had "picked up" his opponent. At first sight it seemed as if the Hun were executing a nose dive. Keenly on the alert the flight-sub depressed the ailerons with a quick yet decided movement. There was no trace of jerkiness in the pilot's actions. All were performed with that smooth dexterity and rapidity that comprised the essential qualifications of a successful airman.
At an aggregate speed of nearly two hundred miles an hour the rival aeroplanes converged. It seemed as if each pilot were bent upon ramming his opponent and sending the colliding craft to a common destruction.
Barcroft, his hands resting lightly on the "joy-stick," was keenly alert to every forthcoming move of his adversary. Already the Hun observer was letting off rounds from his machine-gun in the vain hope that some of the hail of bullets would disable the British seaplane. On his part Kirkwood "stood by," ready at the first favourable opportunity to let the Hun have a taste of the Lewis gun—and the opportunity was not yet.
Suddenly the German monoplane straightened out, then, lifting, attempted to pass above the seaplane. Quick as a flash Barcroft grasped the situation. Round swung the British machine, though not before a dozen holes had been ripped in her wings, as, banking steeply, she presented a vast spread of canvas to the hostile machine-gun.
Through the turning movement of his opponent the Hun had gained nearly three hundred yards. The observer, swinging his gun aft, was busily engaged in fitting a new belt of ammunition.
It was now Kirkwood's chance. The hostile monoplane was still within easy range, although momentarily her superior speed was taking her further and further away from her pursuer. She had broken through the cordon. Ahead was a straight, unimpeded run for home.
The Lewis gun began to splutter. Half—three-quarters of the drum of ammunition was expended without tangible result. The Hun observer, too, had got his machine-gun in working order and was pumping out nickel at the rate of five hundred rounds a minute.
It was a duel to the death. At that dizzy height no human being could fall and reach the surface of the sea alive. No cover, no sheltering trenches protected the four combatants. In the blue vault of heaven they were compelled to kill or be killed, or even deal out complete and horrifying destruction to each other.
"Got him, by Jove!" shouted Kirkwood, as the Hun at the machine-gun threw up his arms and toppled inertly across the barrel of the weapon. For perhaps ten seconds he hung thus, till the monoplane, rocking through an air-pocket, tilted violently. For a brief instant the body trembled in the balance, then slipping sideways the dead Boche toppled over the edge of the fuselage and fell like a stone through space.