contemplating a journey by the now famous channel ferry, derek was soon to learn how, at the very last moment, official plans are apt to be altered.

for some reason, possibly on account of information received of possible enemy action at sea, the train-boat was ordered to stand fast, while a telegraph message was received, ordering second-lieutenant daventry to proceed to an aerodrome in sussex, and to fly a large battleplane across to an aviation camp near etaples.

"this is some luck," thought derek; for the opportunity of flying across to france was one that he had yearned for; and, accordingly, he left his kit to be sent across by boat, and took train to the point of his aerial departure.

the battleplane was a brand new machine that had just been delivered from the manufacturers. it had gone through its trials, and, owing to the serious nature of the military situation on the amiens front, was urgently required for the purpose of checking the hun offensive.

besides derek as pilot, the machine carried a crew of four—observer, mechanic, and two gunners. with a wing-spread that far out-classed the celebrated dromedary, and possessing motors of nearly twice the horse-power, the gv 7—such being the official designation of the biplane—was capable of a one-thousand-two-hundred-mile flight without having to alight for petrol.

it was, indeed, a formidable type of battleplane. portions of the fuselage—especially the underside—were armoured with nickel steel sufficient to resist fragments of anti-air-craft shells, while ample protection was afforded to the crew. short of a direct hit, or the smashing of a wing or tail, the machine was able to bear a severe gruelling without becoming hors de combat. being of an entirely novel and formidable type, it was considered to be far and away a match for any air-craft that, up to the present, the hun possessed.

it was within two hours of sunset when derek started on his maiden cross-channel trip. a steady north, or following wind gave every indication of holding, while an almost cloudless sky betokened a continuance of fine weather.

with her full crew and equipment, the gv 7 "took-off" magnificently, the enormous fabric answering quickly to the controls. compared with the old dromedary, with its short wing-spread and stumpy fuselage, the battleplane was as a battleship is to a cruiser. there was an almost complete freedom from lack of space, which contributed in no small degree to comfort, although all controls were within easy distance of the pilot.

before the machine was over the english coast, an altitude of seven thousand feet was attained. in the clear atmosphere, the low cliffs of france were clearly discernible. it seemed as if a small silvery streak of water—which to the ordinary traveller to the continent is an object of dread—was a very negligible quantity. by air, great britain and france, one-time sworn foes, were to be united in a bond of mutually self-sacrificing friendship.

gv 7 proved herself to be an exceptionally rapid climber, rising at a steep angle without evincing any tendency towards side-splitting. as steady as a rock, she settled down to her flight across the silvery streak of the english channel, and, although throttled down, her speed was not far short of ninety miles an hour.

within five minutes of passing over the coastline, the observer called derek's attention to a mere speck on the waters. by the n.c.o.'s manner, it was evident that something was amiss.

"boche 'plane up to mischief, sir," reported the man by means of the voice-tube. "steamer getting it hot, i fancy."

without hesitation daventry dived steeply, the men standing to their machine-guns and bomb-dropping gear. by the aid of glasses the speck, which was momentarily increasing in size, resolved itself into a large tramp steamer. she had just starboarded her helm in order to maintain a zigzag course, while clouds of smoke pouring from her funnels indicated that the engineers and stokehold staffs were hard at work in their efforts to shake off pursuit.

image: 04_rescue.jpg

[illustration: gv 7 to the rescue!]

"'tis a boche 'bus!" exclaimed the observer, as a circular cloud of white smoke shot up a few feet astern of the tramp. "by jove, what a beauty!"

whether the n.c.o. was in earnest, or merely speaking sarcastically of the hun machine, daventry could not determine. his attention was centred upon the darting form of a possible antagonist, who, as yet, was ignorant of the british biplane's presence. the boche machine was remarkable for the unusual appearance of its wings, or rather non-appearance, for they were made of some sort of transparent fabric that rendered them almost invisible. it was only when the aeroplane banked steeply as she hovered over her intended victim that the rays of the setting sun, glinting on the tilted planes, revealed the presence of the v-shaped wings. even the black cross was absent, as far as the planes were concerned, although they were painted on the top and sides of the fuselage. the elongated body was fancifully decorated in various colours, the whole resembling a freak machine that might, or might not, prove to be a tough customer.

"wonder if it's biggs's old pal, count von peilfell?" thought derek. "it's not a seaplane, and the guy is a jolly long way from his base."

a thousand feet—five hundred—three hundred.

"let him have it," signalled derek.

the staccato of the lewis guns mingled with the roar of the motors. apparently taken completely by surprise, the hun side-slipped, spun on one wing for several seconds, and then burst into a furnace of smoke and flame.

boldly into the trailing smoke plunged gv 7, keenly in pursuit of the crippled and falling hun. half-blinded by the smoke, and choking from the pungent fumes, derek held on, until a rapid glance at the altitude-gauge showed him that he was but a few feet above the sea.

like a meteor, the british battleplane flattened out, and, emerging from the smoke, began to encircle the fiercely-burning wreckage on the sea. it was not until several minutes had elapsed that the vapour cleared, and derek realized that he had been badly tricked.

the hun, in diving, had thrown out a novel kind of smoke-bomb, and, surmising that the british biplane would dive in pursuit, the german had climbed to a terrific height, unnoticed by his too eager and credulous antagonist.

"we've been on a dud trail," muttered derek disgustedly, and, glancing aloft, he saw the faint outlines of the boche machine, looking much like a tadpole, scurrying home at a rapid pace. the advantage of altitude, and the intervening distance, rendered pursuit impracticable, and, reluctantly, daventry had to recognize tactical defeat.

he had, however, saved the tramp steamer from destruction, and, since his orders were definite, he now had no option but to resume his flight for the battle-front. nevertheless the wireless operator was busily employed reporting the presence and direction of a hun to the aerial-patrol off dunkirk, and, with luck, the strong allied air squadron ought to be able to intercept the returning raider.

the tramp expressed her gratitude by giving a series of whoops on her siren, and, steadying on her course, headed towards a number of m.l.'s, which, called up by wireless, were hurrying to her aid.

the sun was still above the horizon when derek "cut out" preparatory to descending at the aerodrome. miles away the sky was stabbed by countless flashes that more than held their own against the glow of departing day, while the air reverberated with the roar of heavy guns. in spite of the volplaning air-craft's rush through the air, and the shriek of the wind, the ceaseless rumble was plainly audible. ahead, right and left, as far as the eye could see, the lines of flashes continued. a big engagement, not merely a series of local operations, was in progress.

the sergeant-observer actually grinned in his officer's face, for there is such a thing as a companionship of the air that makes small beer of cast-iron methods of discipline.

"we're not too late, after all, sir," he exclaimed through the voice-tube. "they're going it hammer and tongs."

making her distinctive signal, gv 7 circled around the landing-ground until the coast was clear, for there was much aerial activity in progress, machines rising and descending almost ceaselessly.

"all clear, sir!" reported one of the battleplane's crew, as a tri-coloured flare rose from the gathering shadows betwixt the hangars.

"right-o!" rejoined derek. "down we go."

a succession of jerks announced that the battleplane had renewed acquaintance with the earth, although it was the first time as far as the soil of france was concerned.

derek stood up in his "office" and pushed back his goggles. the scene that awaited him was very much like that of an aerodrome in england. there were mechanics hurrying towards him, while in a few moments a couple of flying-officers strolled up.

"new 'bus?" enquired one casually. "just out? what's doing in town?"

daventry did his best to reply to the widely-divergent questions, and dared to ask how things were going out there.

"doing? heaven only knows!" replied one of the two officers. "apparently we're doing a sort of fox-trot backwards. 't anyrate we've orders to pack up before morning. the boche is, we understand, about twelve miles away, and during the last three days has been pushing on at three miles a day. come along to the mess and see what's going."

the hut signified by the name of mess was the result of a poor attempt to turn an inadequate building into a dining- and living-room for hungry airmen. the furniture consisted of a few trestle-tables each covered with an army blanket of different shades. long wooden stools contrasted with aggressive hardness with the dark browns and greys of the tables, while a solitary chair, resting insecurely on three legs, indicated the appointed place of the c.o. in one corner was a much-battered piano, a partly-reconstructed derelict from a now demolished chateau. the inevitable gramophone, which proclaimed in wheezy tones "the parson's waiting for me and my girl", occupied the top of the piano in partnership with a decrepit melodeon. the windows were heavily curtained with blankets, while the blue-washed walls were adorned with a vivid selection of kirchner prints.

curled up around the almost red-hot tortoise stove were some of the animals that are to be found in every well-ordered mess: three dogs and a large yellow-and-white cat, all serenely indifferent to a lively scrap between two lively young bloods who were settling an argument as to who should not pay for certain liquid refreshment. the rest of the mess were deriving exhilarating enjoyment from the friendly little bout, the din completely outvoicing the gramophone's announcement as to a certain padre's present occupation.

there were present between twenty or thirty officers. some, just back from a desperate errand across the enemy's lines, were still wearing their yellow-leather flying-coats, and, while watching the struggle between two of their chums, were warming their benumbed hands at the stove. others, about to fly, were similarly attired. others, off duty for a very limited space of time, were rigged out in a medley of garments culminating in british warms and much-soiled trench-coats. all were smoking cigarettes of a brand known throughout the british army and royal air force as "gaspers", and, judging from the buzz of conversation, their thoughts were far away from the war, despite the fact that the forefront of the much-advertised hun offensive was now but a few miles off and was still advancing.

"blow in!" was derek's newly-found friend's invitation. "blow in, and make yourself at home. sling your gear over there,"—indicating a small mountain of thrown-off coats—"sorry there's no clothes-rack. last time jerry came over here dropping eggs our mess-room got it. we haven't replaced camp equipment yet. hallo! no dinner ready yet? what's up with the messman this evening?"

just then an orderly stepped briskly into the room, and, saluting, delivered a sealed envelope to a small, undersized youngster whose badges of rank proclaimed him to be a major. although barely twenty-four this officer was a senior major, and wore across his right breast a double row of ribbons belonging to much-prized distinctions. in addition he had "put up" three wound-stripes.

almost languidly the major opened the envelope. it was about the fiftieth he had received that day. then, dismissing the orderly, he strode across the room and pinned the contents to the notice-board.

"urgent, you fellows!"

bedlam ceased. the combatants broke away, and arm in arm joined in the throng around the board.

it was an order from the general officer commanding, briefly stating that the enemy was still advancing in force and the squadron was to attack by low-flying machine-gunnery. "it cannot be expected," concluded the order, "that this work can be performed without considerable loss."

brief and to the point. the officers read it carefully. there was silence in the room. everyone knew what the work entailed. some, perhaps many of them now present, would go and not return. the already heavy casualty list of the r.a.f. would be greatly augmented.

"some stunt this!" remarked a voice. "but i say; what's wrong with dinner? ring the bell for that messman, somebody."