"A willingheart goes a long way," declared Desmond Blake. "On the other hand there's a verse:—
"Give every act due deliberation;Make no man your friendUntil his heart you know."
"We'll risk that," rejoined Dick.
"In that case we'll compromise matters," said the inventor. "Since you have offered yourselves in all good faith, we'll run in joint harness for the next fortnight. I'll show you the ropes, and if at the end of that time you wish to dissociate yourselves with the enterprise you may. In a fortnight's time I hope to be ready for an experimental flight to London just to show the authorities what my invention can do."
"Hope the weather will be warmer," said Athol. "It must be cold work flying on a day like this."
"Not in a covered-in artificially-heated chassis," corrected Desmond Blake. "Even the pilot's and observer's heads are protected by transparent screens."
"I should have thought that the snow driving against the screen would obscure it," remarked Dick.
"Then we'll put your theory to the test," declared the inventor briskly. "No time like the present. I'll open the doors to their widest capacity and fill up the tanks with fuel. You might also fix the two automatic guns to their pedestals; it's as well to have a trial flight with the normal weights on board."
The hose communicating with a powerful suction pump was coupled on to the tanks, and fifty gallons of fuel taken on board.
"I've doctored the petrol," explained the inventor. "I introduce a quantity of benzine in tabloid form. The result is—I am judging by results obtained on a car—that I can get fifty per cent. more power out of the motors. Now hold tight for the take off."
The floor of the shed being slightly on the down grade the vibration of the engines was sufficient to set the battleplane in motion until it reached the open space in front of the doors.
It was now snowing heavily. The tops of the pine trees were almost hidden in the blurr of falling flakes.
"Pull that slide over the rearmost seat, Dick," ordered the inventor. "It won't be needed this trip. That is good. Now, stand by with the ignition lever. That will be your only job for a while."
Desmond Blake had climbed into the pilot's seat, and had raised a hinged wind screen fitted with side wings and overhead covering. Athol followed his example, taking his place at the second, or machine gunner's seat.
The snow laden air reeked with petrol fumes and the smoke from the exhaust, but the noise of the motors was hardly audible without. The throbbing sound seemed to be confined to the interior of the fuselage.
Both lads, agog with excitement, held on tightly. For some seconds nothing appeared to happen; then with a sudden, powerful jerk the battleplane seemed to stand on end. Kept in a natural sitting position by a delicately-balanced seat, the two chums were forcibly aware of a pain in their necks, as if they had banged their heads violently against a door-post. The sudden starting or stopping of a lift was nothing to the jerk, for the battleplane had to clear the tree-tops with little lateral space to spare.
For the present they could see nothing except the whirring tips of the wings and the streaks of white as the machine soared against the falling snow. Already the manometer registered a height of four hundred feet and the needle was still moving rapidly round the dial.
Presently the fuselage assumed a horizontal position. The movement was now regular and free from vibration, for the direction of flight was no longer in an inclined motion.
"Easier than I thought," remarked the inventor.
Without raising his voice he could comfortably communicate with the rest of the crew, since the rush of air did not disturb the interior of the fuselage. Nor did the snow accumulate upon the wind-screens as Dick had surmised, for the nature of the transparent substance caused the impinging flakes to disperse without any suspicion of moisture being deposited upon the glass.
Owing to the design of the wing-screens it was now possible for the lads to learn and observe the ground almost immediately below them. Eight hundred feet beneath was a blurr of white, across which were traced several winding dark lines, for the battleplane had run out of the falling snow and was now heading southwards.
"Not much of a day for observation purposes," said Blake, who had relinquished his grip on the levers and was now trusting solely to the "stabilisers" or automatic devices for maintaining a straight course. "We are now over Ludlow. That patch is the ruins of the castle. You can just discern the town."
"I thought Ludlow was built on the side of a steep hill," remarked Athol.
"It is," assented the inventor. "That street is almost as steep as a roof of a house. Altitude tends to impart an appearance of flatness to the landscape, especially in the snow. We'll turn now, and follow the Shrewsbury railway. I don't like getting too far afield on an experimental run when so many landmarks are obliterated. Now, Athol, make your way for'ard and I'll show you how to manoeuvre the plane. Dick will have his turn later. It is essential that every man of the crew should know how to handle the steering and elevating gear."
For half an hour Desmond Blake kept his understudy hard at it, showing him how to make the battleplane bank almost horizontally, and how to change the speed gear to enable the wings to overcome the force of gravity during the vertical flight.
"You'll do," declared the inventor admiringly. "Now back to your perch. We are going to have a shot at looping the loop."
Desmond Blake waited until Athol had regained the gimballed seat, then, depressing a lever that had the double effect of lowering the gearing of the engine and elevating the "aerilons," or wing-tips, he caused the battleplane to soar almost vertically upwards.
The lads wondered why the terrifically acute angle of ascent did not cause the fuel to flow to the rearmost of the four connected tanks, and thus affect the aircraft's lateral stability. The inventor, glancing over his shoulder, must have read their thoughts.
"Climbing to get a better chance in case she jibs," he called out. "No need to worry about the petrol. Each tank has a reserve valve that only operates when the angle of inclination exceeds fifteen degrees."
The arrangement of the tanks was another instance of Blake's forethought. At normal flying positions the petrol in each tank was practically at the same level in order to ensure constant trim of the machine. But directly the tilt of the battleplane tended to allow the volatile spirit to flow to the lowermost tank, automatic valves in the connecting pipes came into action, thus causing each tank to retain approximately the same weight of liquid fuel.
For three minutes the battleplane climbed steeply and at a high speed that had never yet been approached by the most daring aviator. Then, following a hasty caution from the pilot, the aeroplane began to describe a circle in a vertical plane. Although the seats retained their normal positions, the centrifugal force tended to throw Athol and Dick off their balance. The next moment their heads were within a few feet of the up-turned floor of the fuselage, while their feet were dangling in the space enclosed by the wind-screens. Five seconds later the battleplane had regained its normal position, having described a complete loop of a radius of less than a hundred feet.
"That's good!" exclaimed the inventor with pardonable pride. "Now look out to enjoy the sunshine."
To the lads' surprise the battleplane was bathed in bright wintry sunshine. The aeroplane had emerged above the bank of snow clouds and was cleaving her way through the clear air. Away to the south-west the sun was low in the heavens, for it was now within an hour of sunset.
"Time to get back," declared Blake briskly. "We've got to drop through the snow-clouds beneath, and trust to luck to pick up our bearings. 'Fraid I've overstepped the bounds of discretion, but it was jolly well worth it."
Actuating a lever he "locked" the wings. Like a giant seagull swooping down from a lofty cliff the aeroplane began a steady volplane towards the bank of clouds a thousand feet below.
At a speed of well over a hundred and fifty miles an hour the battleplane cleft the bank of suspended vapour. Almost pitch darkness succeeded the clear sunshine of the upper air. The sudden transition temporarily blinded the three aviators.
Desmond Blake spoke not a word. With his eyes fixed upon the dials of the manometer he gauged the earthward flight. At five hundred and fifty feet, an altitude well above that of the highest hills on the Welsh border, he checked the descent. Although the gloom was now less it was still impossible to discern anything of the country beneath. Evidently the battleplane was encountering a snowstorm heavier than she had previously experienced.
Standing by, ready to "flatten out" at the first sign of terra firma, the inventor allowed the machine to continue its downward flight, although at a greatly retarded velocity.
Suddenly he thrust the vertical rudders hard over, at the same time unlocking the wing mechanism. As he did so he had a momentary glimpse of a tall slender spire within fifty feet of the tip of the left wing. Immediately afterwards the battleplane almost skimmed a lofty pinnacle that resolved itself into another snow-outlined spire.
"By Jove!" ejaculated Blake as he set the battleplane to climb above the danger area. "We're slightly out of our bearings."
"Where are we, then?" asked Dick, who had also seen the fleeting vision.
"Over Coventry," replied the inventor. "We've narrowly escaped colliding with two of the city's three famous spires. Take her, Athol, and keep her as she is while I look at the map. It will be a compass course back, with a good deal of guesswork thrown in."
A hurried consultation told Blake that, allowing for the almost cross-set of the northerly wind, half an hour's flight in a north-westerly direction ought to bring them within recognisable distance of home.
"Birmingham's beneath us," observed Blake after a few moments' interval. "Fine city, Birmingham, but a nasty place if one has to make an involuntary landing."
He had hardly uttered the words when with a disconcerting jerk the motors faltered, picked up for a few pulsations, and then ceased firing.
The battleplane began to drop towards the labyrinth of buildings that, hidden by the thickly-falling flakes, lay less than three thousand feet below.
Notfor one moment did Desmond Blake's presence of mind desert him. Quickly locking the wings in position to enable the battleplane to maintain a maximum glide he turned her "down wind." Volplaning in the teeth of the stiff northerly breeze would, he knew, result in a cross-country gain of, perhaps, a mile or two; whereas, gliding with the following wind there was more than a sporting chance of covering sufficient distance to get clear of the thickly populated outskirts of the Metropolis of the Midlands.
Following the stoppage of the motors Dick slipped from his seat and made his way along the floor of the fuselage till he came to the silent machinery. Switching on an electric torch, for it was now dark within the "hull" of the battleplane, and with the failure of the motors the dynamo-run lamps had gone out, Dick made a hasty examination.
"Ignition," he reported. "Magneto, I fancy."
"Guessed so," rejoined the inventor, laconically. "See if you can rectify matters. I'll keep her steady as long as I can."
Volplaning at fifty miles an hour does not give one much time for effecting adjustments. Before the lad had been able to verify his suspicions a peculiar motion warned him that the battleplane was describing a semi-circular swoop. Ten seconds later, with hardly a perceptible jar she came to earth, or rather, landed in a deep snow-drift.
"Had to risk it," declared Blake cheerily. "This will do for the present. Night's coming on apace. Fortunately there are plenty of emergency rations on board."
"Where are we?" asked Athol.
"Goodness only knows," said the inventor. "All I know is that we just skimmed the tops of a tall building. It wouldn't be a bad idea to land and have a look round. Nothing like fixing one's bearings in case we have to clear out in a hurry."
Although the fuselage when at rest had a normal inclination of about forty-five degrees it now barely exceeded fifteen. On alighting the airmen discovered that the battleplane was resting in the snow on a shelving slope. Twenty feet from her bows was a stone wall in a ruinous condition. Only the drag of the snow drift had prevented the battleplane from hurling itself "nose-on" against the formidable obstruction.
Already the twilight was falling, the dim light rendered still fainter by the steady drive of heavy flakes. Away to the right a dim outline, silhouetted against the afterglow, denoted the position of the building against which the battleplane had so narrowly escaped being hurled.
"A ruined castle," exclaimed Athol.
"And, to me, a familiar spot," rejoined the inventor. "We couldn't have lighted upon a better place. This is Kenilworth. There is little fear of interruption, it is late in the day, and people would not be tempted to wade through the snow drifts even if the grounds are not closed. Yes; we'll do here very nicely. There's plenty of room for a 'take off.' Now for a meal, then we'll tackle the repairs. I don't propose making a fresh start until just before daybreak."
Returning to the battleplane the three aviators "battened" down to guard against the possibility of any stray ray of light betraying their presence. Two battery-charged electric lamps gave quite a brilliant illumination. The meal, though frugal, was heartily appreciated, while thanks to the amount of heat still retained by the radiators fed by the exhaust the temperature bordered upon sixty degrees.
"One must be ready to profit by slight misfortunes," remarked Blake during the the meal. "I have an idea. I'll have separate magnetos to each engine."
"Will that help us?" asked Dick. "If one engine fails one of the wings will cease beating and the other will go on flapping. The battleplane would be like a duck wounded in one wing."
"So she would," admitted the inventor dubiously.
"Separate magnetos by all means," continued Dick, "but it would be well to fit a free wheel sprocket on the main shaft of each engine, and arrange it so that each motor actuates both wings. Then if one engine falters or stops the other will continue to propel the battleplane. Of course you would only have half the power, but that would be sufficient to keep her in the air."
Desmond Blake thought deeply for a few minutes.
"By smoke, Dick!" he exclaimed. "You've solved a knotty point. We'll make the necessary alterations directly we return. You are quite right about the power of each motor. Each possesses one and a half times the lifting power necessary for the battleplane."
By nine o'clock in the evening the adjustments to the magneto were satisfactorily carried out, and the battleplane's wings having been folded to escape an accumulation of snow, the airmen turned in for the night.
As Blake had surmised the night passed without interruption. Little did the inhabitants of the picturesque village of Kenilworth suspect that the most ingenious flying machine that the world had yet possessed was resting quietly in the snow-covered courtyard of the famous mediaeval ruin.
So soundly did the two lads sleep in their comfortable bunks that the first intimation they had of the arrival of another day was Desmond Blake's voice exclaiming,
"Now, then, you fellows. Five o'clock and a fine morning."
A cup of hot coffee and some biscuits having been served out, the airmen prepared to resume their flight. It was still twilight. Snowflakes were falling, although not with the violence that characterised yesterday's storm. From a not far distant farmyard cocks were lustily heralding the dawn.
Silently, under the guidance of the masterhand, the huge mechanical bird left its roosting place on the snow covered ground and soared swiftly upwards until it attained a height of two thousand feet.
Suddenly a huge, ill-defined shape lurched past the battleplane, passing less than two hundred feet underneath. In spite of the terrific speed, for the two objects were moving in the opposite direction and at an aggregate rate of one hundred and eighty miles an hour, both lads recognised the shape as that of a Zeppelin.
Desmond Blake saw it, too, and acted promptly. In a few seconds the battleplane had made a semi-circular motion and, "all out," was following the night-raider.
Athol sprang to the machine-gun but the pilot waved his hand to indicate that the weapon was not to be used. Already the Zeppelin, having gained a great distance during the change of direction on the part of the battleplane, was out of sight.
"No use," he exclaimed hurriedly. "Only dummy cartridges. Must blame the Defence of the Realm Act for that."
Seven minutes later the Zeppelin was again sighted. Apparently she had been engaged in a raid over the Midlands and had lost her way. She was moving jerkily, and was down by the stern. Whether that was owing to injury from anti-aircraft guns or merely through the accumulation of snow on the upper part of her envelope the lads could not decide.
Unperceived by the crew of the Zeppelin the battleplane soared majestically overhead until a vertical distance of less than a hundred feet separated the gas-bag from her winged rival.
"If we had ammunition we should have her at our mercy," remarked the inventor.
"Take charge for a few minutes, Athol. I want to give her a little reminder of our meeting."
The lad gripped the steering levers. So strong was his faith in the masterpiece of the inventor that he handled the swiftly-moving battleplane as faultlessly as if his acquaintance with the mechanical bird had been of two years' duration rather than of a few hours.
Meanwhile, Blake descended to the interior of the fuselage, returning presently with a long steel marline-spike. Through the hole in the rounded end he threaded a string of red, white and blue ribbons for the joint purpose of steadying the improvised dart in its flight and in order to leave no doubt in the minds of the Huns of the origin of nationality of the weapon.
Then, clambering into the seat vacated by the deputy pilot, Blake lowered one of the wing-screens and poised the marline-spike over the side.
"Faster," he ordered.
Dick touched the lever actuating the sparking-gear. Perceptibly the battleplane increased her speed until she overlapped the unsuspecting Zeppelin by almost two-thirds of the latter's length.
Blake released his grip of the rough and ready dart. For a couple of seconds it seemed to fall well in front of the swiftly-moving Zeppelin, then, its course describing a gradually increasing curve, it was observed to be making for the huge target.
With a thud it struck the flattened part of the upperside of the envelope about fifty feet from the tail. Completely perforating the aluminium sheeting it vanished, leaving a few fragments of streamers to mark the palpable hit.
"There'll be some gas lost there, I'm thinking," remarked Blake grimly. "Up helm, Athol. We have no more missiles at our disposal. One thing, we've had practice at bomb-dropping."
In a few seconds the errant Zeppelin was lost to sight in the snow-laden atmosphere, as the battleplane was steadied on a course that was to bring her back to her hangar.
"There is our base," announced the pilot, pointing to a clump of snow-laden pines almost hiding a lofty conical hill. "Make sure of your bearings, lads; you never know when the knowledge will come in handy. Now, stand by."
Skilfully Desmond Blake brought the battleplane to a standstill with her nose within five feet of the doors of the shed.
"Now for a proper breakfast," he exclaimed cheerfully as the crew alighted. "It won't take long to house the little beauty, then——"
He stopped abruptly, his hands gripping the half-open doors.
"The deuce!" he ejaculated.
"What'swrong?" enquired both lads anxiously, for the worried expression on the usually calm features of the inventor told its own tale.
In his agitation Blake failed to make reply. He dashed into the shed, followed by his two assistants. Everywhere there were signs of disorder as if some intruder had hastily overhauled the secrets of the jealously guarded spot. The high tension wire that had previously baulked a nefarious attempt had been severed by means of a pair of insulated wire-cutters. The lens of the tell-tale camera had been smashed and the dark slide removed and exposed to the light.
A safe, cunningly built into a concrete pier of the shed, had been forced open and its contents removed.
"The spy has secured the plans; that's pretty evident," he declared. "We can do no good here at present. What I want to find out is how the fellow forced his way into the grounds."
Accompanied by Athol and Dick, the inventor left the shed and hurried across the snow-covered ground. Already the footprints of the intruder had been obliterated by the falling flakes. He could not have chosen a better time for his successful attempt.
Along the path through the shrubbery the crew of the battleplane hurried. At the inner gate the first sight that met their eyes was the body of one of the bull-terriers half buried in the snow. The other animal was discovered dead in the bushes, whither it had crawled before expiring. Both animals had been poisoned.
In the little lodge was the unconscious form of the aged porter. Evidently he had put up a stiff fight, for there was blood upon the floor, and a revolver with two chambers discharged was still grasped in his right hand.
Blake bent over his devoted servant.
"He's alive," he announced. "I can find no trace of an injury. He must have been tackled by two men. He's been chloroformed."
The inventor's first task was to restore the unconscious man. His anxiety on the porter's behalf seemed to banish all other thoughts from his mind. The loss of the almost invaluable plans were as naught compared with the state of his faithful retainer.
"Shall I go for a doctor?" asked Athol.
Blake shook his head.
"I'm used to a land where doctors are few and far between," he replied. "That makes every man there more or less of a medico. You might start that fire again, Athol, and get a kettle on."
Having waited until the patient had recovered consciousness, Desmond Blake and Dick left the lodge, Athol having volunteered to remain with the victim of the outrage.
Letting himself in by means of a sidedoor the inventor soon found that the house had not been an object of the spies' investigations. The old butler was still asleep, ignorant of the attempt upon his brother the porter.
"This little business has upset my plans, Luck," remarked Blake. "Or, rather, it will force my hand. It's no use trying to track the thieves. For one thing we have no clues; for another we simply haven't the time to waste. In the likely event of those plans reaching Germany, another month will result in the appearance of hostile battleplanes built to my specifications. So our task is to convince the War Office of the outstanding nature of my invention, and get the Royal Aircraft Factory people to set to work as hard as they can."
"You will have to make another set of working plans, I suppose?" remarked Dick.
"No, fortunately. As it happens I have both duplicate and triplicate tracings deposited at a London bank. However, that is not our immediate concern. What I propose doing is this. I'll motor into Church Stretton this morning and take old Harvey to the cottage hospital. Athol and you might make up arrears of sleep. This afternoon we'll tackle that little job you mentioned in connection with the dual drive. There are also a few adjustments necessary, which I noticed during our trial trip—not important, but certainly desirable. While I am in Church Stretton I'll engage a man and his wife as caretakers of the house while we're away. One never knows when we may be back. To-morrow at nine o'clock I intend starting on our flight to London."
Desmond Blake's plans worked smoothly. During the afternoon the suggested alterations to the driving transmission gear were satisfactorily carried out, and everything made ready for the momentous flight.
"I'm sending something of the nature of an ultimatum to the War Office," he remarked during the course of the evening. "You see we have to announce our arrival, otherwise the anti-aircraft guns might favour us with their unwelcome attentions. On the other hand it's worse than useless asking formal permission from the authorities to fly over the Metropolis. The application would drift to and fro between a dozen or more departments. Every little tinpot in office would have some remarks to make—I know them of old. The chances are that I would get an evasive reply in about a fortnight. Good heavens! If we had an Admiralty and a War Office purged of the somnolent civil element the war would be over by this time. So I've just cut in with a bald announcement. I've left a telegram to be dispatched at nine to-morrow—the time we start—stating that the Desmond Blake battleplane will manoeuvre over the Horse Guards Parade at 10 a.m. But we'll turn in now. It's getting late, and we've a full programme in front of us tomorrow."
"Do you mind if we sleep on board the battleplane?" asked Athol.
"Mind? No, of course not. But what's the object?"
"We've been talking it over," said Athol. "We thought that perhaps those spy Johnnies might pay us another visit."
"Hardly likely," replied Blake grimly. "They've collared the plans, and those will keep them quiet."
"I don't know so much about that," rejoined Dick. "They might think that that is our opinion, and consider it a favourable chance of returning and doing damage to the battleplane. That would give them a tremendous start."
"Perhaps you're right," declared the inventor. "Now I come to think of it there is a possibility that the rascals will attempt to culminate their efforts. We'll all sleep on board, and take turns at keeping watch. I haven't bothered to fix up that high tension wire again. 'Fraid they know too much. We'll arm ourselves and be ready to give them a warm reception."
"By the by," remarked Dick, "whilst we were repairing the side-car wheel I noticed a 'buzzer' in the workshop."
"Yes," replied Blake. "I bought it to practise Morse signalling. Found myself awfully testy, by the by. But why do you ask?"
"We could fix it up on board, muffle the sound and connect the battery with a push on the door of the shed," said Dick. "We could arrange it that as soon as the door opens wide enough to admit a man a circuit would be complete."
"Might try it," admitted Blake. "But you must remember these fellows are prepared for all sorts of dodges. Well, we'll adjourn at five minutes' intervals. The great thing is to get on board without being seen, for ten to one if these rascals intend paying us another visit they will be keeping a sharp look-out on the house."
With a loaded revolver reposing in the side pocket of his coat, Athol was the first to make for the shed where the battleplane was housed. Slipping quietly through an open window in the rear of the house he crept stealthily through the snow, keeping well under the cover of the pinetrees. As an additional precaution he walked backwards, so that should the spies subsequently examine the ground they would find that the footprints led away from the shed.
It seemed a long five minutes waiting for Dick to rejoin him. The eerie shape of the battleplane, looming faintly through the darkness, and the possibility that even now some miscreant might be hidden in the hangar, gave the lad an unpleasant sensation that he had not experienced since his first night on sentry in the first-line trenches of Flanders.
At length Dick arrived. Not a word was spoken. They stood motionless until Blake joined them. Still in silence they ascended the aluminium ladder and gained the interior of the fuselage. Already it had been arranged that Athol was to have the first watch—from nine to midnight. Blake had insisted upon keeping the next three hours. He knew what the mental strain of that watch meant, when a man's diurnal vitality is supposed to reach its lowest ebb. Out of consideration for his young and efficient helpers he knew that by taking the middle watch each lad would have six hours' continuous rest, unless something unforeseen occurred.
Lying at full length upon the floor of the fuselage Athol could command a considerable extent of the shed, for the aperture by which the crew had gained the interior of the battleplane had purposely been left wide open. The double doors of the building had been locked and the key removed, while Dick's contrivance had been fixed up, the "buzzer" lying within a foot of the watcher's ear.
The lad had no idea of the time. Already it seemed as though he had been for hours at his post. The silence, broken only by the moan of the wind in the pines, and the occasional thud of a heap of accumulated snow from the roof of the hangar, was oppressive.
"What's that, I wonder?" thought the lad as, after a seemingly interminable lapse of time, a faint hissing, bubbling noise caught his ear. For some seconds he listened intently. Then came the unmistakable odour of the fumes of a powerful acid, mingled with the spluttering of the drifting flakes as they came in contact with the hot metal.
The miscreant, whoever he might be, had fought shy of the task of picking the lock, and was employing either sulphuric or nitric acid.
Athol knelt up, gripping the coaming of the aperture and straining his ears. Then, just as he was about to steal softly to his companions, he felt a hand laid lightly upon his shoulder.
Desmond Blake had also detected the signs of the miscreant's attempt.
Without trusting himself even to whisper, Blake began to apply a series of light touches to his assistant's arm. Athol, quick to grasp the significance, understood. The inventor was employing the Morse system of communication.
"No action till I give the word," he tapped out. "Wake Dick."
Although his chum was sound asleep Athol succeeded in rousing him in silence, and the three airmen gathered round the aperture of the fuselage, awaiting developments.
Quite half an hour passed; then came the rending of the chemically-treated corrugated metal sheeting. A muffled exclamation of pain followed by a guttural oath plainly indicated that the fellow had burnt himself with the powerful corrosive.
Crawling through the opening the intruder hung a great coat over the hole, to trap any rays of light from passing without, and switched on an electric torch. For some seconds he stood gazing at the mechanical marvel he meant to destroy. His scientific curiosity made him temporarily set aside his purpose, for still holding the torch he began to swing himself up the girder-ladder communicating with the interior of the apparently untenanted battleplane.
The reflected glare of the upturned torch made it easy for the lads to follow the inventor's unspoken directions. Cautiously they backed until they had placed the motor space between them and the aperture towards which the fellow was climbing.
The man seemed in no hurry, for some minutes elapsed before his head and shoulders appeared in view. Then came another pause as, sitting on the coaming with his feet resting on the topmost rung of the ladder, he flashed his light around the interior of the mechanical bird.
The miscreant had little of the accepted appearance of a spy. He was slight of build, although his head seemed out of all proportion to his body. His features were round and florid, his eyes—as far as the glare of the torch permitted them to be seen—large and exhibiting a docile expression like that of a well-cared-for household cat. Encountered under ordinary circumstances one would without hesitation set him down as an easy-going, babyish man devoid both of mental and bodily power.
Judging him from a physical point of view Athol formed a rapid conclusion that either he or Dick could tackle him with one hand.
Still Blake gave no sign. He was too old a campaigner to throw away his advantage by premature action. He resolved to wait until the fellow had moved sufficiently far from the aperture to be unable to make a quick dive for safety.
Presently the German crept forward, still flashing his torch. Evidently there was something that attracted his attention to a greater: extent than did the motors and wing-actuating mechanism.
"Hands up!" exclaimed Desmond Blake sternly, at the same time flooding the interior of the fuselage with the dazzling rays of his electric lamp.
"Sorry—my mistake," replied the fellow coolly. "Mistook this place for a barn, 'pon my word, I did. Beastly awkward mistake, don't you know. Then, seeing what I took to be a novel sort of agricultural implement I was curious——"
"Are you putting your hands up?" enquired the inventor briskly.
A pistol shot rang out. The spy, grasping the still-smoking weapon, threw himself flat upon the floor to await the result of his shot. Dazzled by the glare he had been unable to see his challenger; nor was he cognisant of the fact that the two lads were present. The result of previous investigations led him to believe that the inventor was the only able-bodied man about the place, and, now that the dogs had been disposed of, the odds were level.
Greatly to the consternation of Athol and his chum, Blake began to emit blood-curdling, hollow groans. They were on the point of replying to the rascal's shot when Blake signed to them to keep under cover, punctuating his groans by a series of winks that showed plainly that there was plenty of "kick" left in him yet.
The spy showed no immediate haste to follow up what he considered to be first blood. The powerful rays of the lamp irritated him. Until the brilliant light was put out movements would be too risky. He looked about for something bullet-proof and portable that might serve as a mantlet to cover his progress towards the lamp.
Close at hand was a small teak box containing sand. Blake had placed it on board in case of fire. It was certainly proof against a revolver bullet—perhaps even sufficient to stop a rifle-bullet.
Stretching out his arm the spy grasped the edge of the box and began to draw it towards him. The act was his undoing, for a keen knife whistled through the air with unerring aim, and the next instant the German's left hand was transfixed and securely pinned to the hard teak.
"Drop that pistol and put your right hand up," ordered Blake, when the fellow's cries for mercy had subsided sufficiently for the inventor to make himself heard.
The German obeyed. The excruciating pain had overcome all his cunning and spirit of resistance.
"That's reasonable," declared Blake, possessing himself of the surrendered weapon. "Now, lads, lash his ankles. Hang it all! What possessed the idiot to start blazing away? Goodness only knows what damage he's done to the intricate mechanism. And he expected I'd begin to pump nickel through my invention in the hope of plugging him."
"I thought you were hit," remarked Athol.
"Hit? No fear," replied the inventor. "I wanted that fellow to think he had given me a souvenir. It was a jolly good thing I learnt that South American trick of throwing a knife. Didn't think much of it at the time, but, by Jove! it served its purpose."
Having removed the knife and dressed the German's hand, the airmen moved their prisoner aft, securing him to a ring-bolt in the floor. Then bidding Dick mount guard over the captive, Blake, accompanied by Athol, searched the shed and its immediate surroundings.
"There is only one of them this time," declared Blake. "Here are his footprints. This looks cheerful, too."
He stooped and picked up a couple of detonators and a coil of fuse. The spy had set these on the ground at the foot of the tree, apparently with the intention of fixing them up when he had satisfied his curiosity concerning the battleplane.
"It's most fortunate that you fellows suggested spending the night on board," declared Blake fervently. "The battleplane would have been blown sky high before morning if I hadn't listened to your advice. Now I think I'll subject our Hun to a little cross-examination."
Withoutspeaking a word Desmond Blake approached his prisoner and regarded him intently. For a full minute he kept his eyes fixed upon the German, who at first seemed indifferent to the attention paid him.
Presently the spy began to shift uneasily under the searching scrutiny. Try as he would to avoid the penetrating look he found himself unable to withstand the seemingly mesmeric influence. His whole attitude was that of a dog cowed solely by the severity of its master's gaze.
"What is your name?" demanded Blake, breaking the strained silence.
"Sigismund Selighoffer," replied the spy in a strangely subdued voice.
"A native of Germany?"
"Of Halle."
"A spy?"
"Yes." The answer was given with considerable hesitation. It was the man speaking in spite of his inclination to maintain silence and discretion.
"You stole my plans. Where are they?"
"It was my employer, Karl von Secker, who took the plans. We were here last night. He went away yesterday, taking the plans with him; but before he went he gave me orders to destroy this machine."
"You know where he is?"
"On my honour, no. He could not tell me. Perhaps he will make his way back to Germany. It is easy for him to do so."
Blake asked several more questions, not once shifting his eyes from the thoroughly cowed Hun.
"Very good," he concluded. "In a few hours' time you will be handed over to the authorities for trial. If it be any satisfaction to you I might add that you will be the first German—and I hope the last—to set foot on this battleplane."
He turned and went for'ard. Directly his back was turned the spy broke into a torrent of oaths, defying his captors and reviling himself for having given away so much information.
Blake merely shrugged his shoulders.
"Simply the triumph of a strong mind over a weak one," he explained to the lads. "Herr Selighoffer is merely a pawn in the game—a tool of the more dangerous von Secker. Had we no other and more urgent work in hand it would be a delightful task to run von Secker to earth. Man-hunting is, from my personal knowledge, one of the greatest thrills a criminologist can experience. Once I had to track a Brazilian desperado across miles of country—but that story can wait. We must trust the recovery of the plans to the authorities. Now, lads, the pair of you had better turn in again. I'll keep watch, although I don't anticipate any further trouble from prowling Huns. It would be just as well to keep an eye upon that slippery customer, Sigismund."
The rest of the night passed without interruption. At seven the lads arose, bathed and had breakfast; by eight-thirty the battleplane was ready for her flight to London.
"Better thirty minutes too early than thirty seconds too late," remarked Dick.
"H'm! perhaps in this case," rejoined Athol. "Do you remember that morning in the trenches facing the Menin road? We were both a little tardy in turning out to breakfast."
"And what happened?" asked Blake.
"Nothing as far as we were concerned," replied Dick. "Except that we had no breakfast that morning. A shell had landed close to the stew pot and the men with their rations were blown to bits. It was a case of Nah Pooh with them."
Without a hitch the battleplane was brought from the hangar, her wings extended and the motors set running. It had now ceased snowing, and although the ground was still covered with a mantle of white, there seemed every prospect of a fine day.
Making a splendid ascent the machine quickly attained an altitude of twelve thousand feet, and a compass course was shaped to due east. Blake had a definite object in flying high. The air was sufficiently clear to distinguish prominent landmarks, but at that altitude there was hardly any possibility of the battleplane being seen from the earth. He wanted to make his arrival as dramatic and sudden as possible.
"We're touching one hundred and eighty miles an hour now," announced the inventor. "Could do another twenty with ease if we wished. We'll romp there hands down."
"Why this easterly course?" asked Dick, who, having for the time being finished with the motors, had taken his place close to the pilot. "This will land us somewhere in Norfolk if we carry on."
"Only till we pick up the North-Western main line," replied Blake. "There's nothing like a railway to help you to fix a position. In conjunction with a good map a railway lets you know where you are almost to a mile."
Forty-seven minutes from the time the battleplane left the ground a dull haze upon the horizon indicated that the metropolis was in sight. Quickly the intervening distance was covered, until at a height of two thousand feet the airmen were immediately over the Thames.
"Good enough!" declared Blake, at the same time locking the wings. Although the motors were still running they were acting merely as "free engines," ready to be coupled up to the wings in a case of emergency. For the rest of the distance the battleplane was to glide under the attraction of gravity.
Unerringly Blake brought the battleplane towards the gravelled expanse of the Horse Guards Parade. Save for a few persons hurrying across the place was almost deserted. Evidently there was no sign that the aviators were expected. Either the telegram had been delayed or the War Office officials had considered it a hoax.
Suddenly Blake coupled up the wing-mechanism. The beating of the wings caused several of the pedestrians to look skywards. For a second or so they seemed hardly able to credit their senses. Aeroplanes they knew, but the huge mechanical bird astonished them. Right and left they scattered, leaving the parade as deserted as a Siberian plain.
Making a faultless landing the battleplane came to rest. Blake, throwing back the wind screen, awaited developments.
In less than five minutes the machine was surrounded by thousands of curious spectators. It took all the efforts of a strong force of police and soldiers to keep the crowd back.
A way having been cleared through the press a group of military staff officers came up. Amongst them Blake recognised a tall, alert figure in the uniform of a major-general.
"Good morning, Sir Henry!" he exclaimed. "You see I have carried out my promise. Come on board, if you please."
Agilely Sir Henry swarmed up the ladder.
"A top-hole fellow," said Blake to his companions during the officer's progress. "One of the few who were at least sympathetic when I first submitted my plans."
"By Jove, Blake!" exclaimed the newcomer, as, slightly breathless, he gained the interior of the fuselage. "This is rather unexpected."
"I warned you," replied the inventor.
"You did, but, pardon my saying so, I was sceptical."
"But not to the extent of some of your colleagues," added Blake with a tinge of irony. "However, that's done with. Here is the battleplane. I formally offer her to the Government. But before we go farther. Do you know that there is a German spy here—actually within the precincts of the War Office?"
"Good heavens, no!" replied Sir Henry in astonishment. "How do you know that?"
"Optical proof," replied Blake. "If you'll come aft I'll show you."
Briefly the circumstances under which Sigismund Selighoffer was captured were stated, and in a very few minutes the spy was taken from the battleplane and marched off under escort.
"Now as far as I am concerned I hope I'll hear no more about that fellow," commented Blake. "My time is too precious to waste in attending courts-martial. All the same I should be particularly pleased to hear that von Secker, the spy's accomplice—or rather, employer—is run to earth. These fellows pay considerably more attention to outside inventions than does the British Government, I'm sorry to say. But let me show you round. Oh, yes, there's room for a few more," he added as three or four staff officers shouted out for permission to come on board.
With them was one of the civil staff of the War Office. Blake eyed him with a grim smile, for he was the man who had been so prominent in cold-shouldering the inventor but a few months previously.
"Yes, we should like to witness a flight," replied Sir Henry in answer to Blake's proposition. "This ability to ascend almost perpendicularly must be a unique, I might say, rather ingenious property. No, I don't think I will accompany you this trip... another time, perhaps."
One by one the staff officers filed through the aperture in the floor of the fuselage and descended to the ground, amidst the plaudits of the crowd. The civilian official was the last to leave, when Blake touched him on the shoulder.
"You remember me?" he asked.
"Of course, of course I do," replied the man pompously. "I never forget faces. You will doubtless recollect that during our former interview I expressed my opinion——"
"That an ounce of fact is worth a pound of theory," rejoined Blake. "In the circumstances the remark was uncalled for."
"But in my position one has to look for results," stammered the man nervously, for Blake had fixed him with that disconcerting look that had so effectually cowed the spy.
"The result is here," declared the inventor. "You are now going to accompany us for a spin. You are not afraid?"
If he were afraid the official was doubly afraid to admit it. He nodded his head.
"Good!" exclaimed Blake approvingly, as he closed the hatchway at his feet. "Start her up, Dick. Open the exhaust full out. A little noise will shift the crowd."
Dick obeyed, using the "cut-out." Instead of the engines purring almost noiselessly they roared like the concentrated discharge of a battery of mitrailleuses. Then, with a mighty sweep of her wings the battleplane appeared to stand on end. The next instant she was soaring swiftly above the dirty grey stone work of the buildings of the Horse Guards.
The passenger seated in the balanced chair, and seeing the body of the machine turning apparently around a fixed axis, was too astonished even to ejaculate. At length, encouraged by the cool demeanour of Dick and his chum, the official plucked up courage, and, the battleplane having settled down to a steady position, peered over the edge of the coaming.
It was his first sight of London from a height of three thousand feet. He was beginning to enjoy the sensation.
Up and down, describing erratic curves, nose-diving, volplaning and side-slipping with deliberate intent, Desmond Blake carried out his spectacular and demonstrative programme. At one moment it seemed as if the battleplane was diving under the Admiralty Arch; at almost the next it was skimming the aerials on the twin domes of the headquarters of the British Navy. Spinning round, almost on the tip of one wing, the tractable machine circled Nelson's Monument, as if to pay homage to the memory of the one-armed little man whose traditions the Navy of to-day so gallantly uphold. Then, at a rate equal to double that of an express train, the battleplane disappeared from view, to circle over the Nore at a height far beyond the range of the most efficient anti-aircraft guns that the Medway Defences possessed.
Fifteen minutes later the battleplane again came to rest on the Horse Guards Parade. Her passenger, almost speechless with unbounded admiration, did not hesitate to make his amends.
Nor was Sir Henry less enthusiastic.
Gripping Blake's hand as the inventor descended from the battleplane he exclaimed, "Bravo! my dear sir; your aeroplane is simply great. But why the deuce did you make such a show with it? By to-night all the world will know about it."
Desmond Blake shrugged his shoulders.
"It was the only way," he replied. "Nothing else would have attracted the attention of the War Office."
"You certainly have now," said Sir Henry with a smile. "Suppose we adjourn to my office. I'll summon my colleagues and we can discuss terms."
"There are no terms to discuss," objected the inventor. "The battleplane belongs to the Empire unconditionally."