That "air activity," so frequently reported and so casually read in the despatches, means a good deal more than "fleets of aeroplanes darkening the sky," machines dashing and flashing around anywhere up to their "ceiling" of twenty odd thousand feet, shooting holes in and crashing each other, bombing and photographing and contact-patrolling and ground-strafing, and all the rest of it.

There is just as much "air" activity, or if you measure by hours, from two to ten times as much, amongst those men whose sole occupation in life is pushing other people into the air and keeping them there until they wish to come down, and who never have their own two feet off the firm earth. The outsider hardly thinks of this, and there are even a few pilots—a very few, as one is glad to know—who are apt to forget it, while the great majority of the others don't or can't very well make much show of their appreciation of or gratitude for the sheer hard labour of the groundwork in a Squadron that keeps them afloat. I know that most pilots will be glad to have even this one little bit of the limelight turned on a class of men who deserve a good deal more than they get.

No. 00 Squadron broke into the Air Activity period a full week before the Push began on the ground, but a certain amount of "dud weather" gave the pilots some intervening spells of rest and gave the Squadron mechanics a chance to catch up and keep level with their work. But in the last few days before the Push was dated to begin, the air work became more strenuous, because the Huns, evidently suspecting that something was coming off, set their air service to work trying to push over and see what was going on behind our lines, and to prevent our air men picking up information behind theirs. No. 00 was a single-seater fighting Squadron, and so was one of the ots whose mission in life was to down any Huns who came over to reconnoitre or spot for their guns, and, conversely, to patrol over Hunland and put out of action as many as possible of the Hun fighters who were up to sink our machines doing artillery observing or photographing. The more machines one side can put and keep in the air the better chance that side has of doing its work and preventing the opposition doing theirs—it is a pity many aircraft workers even now don't seem to understand the value of this sheer weight of numbers—and since both sides by this time were using their full air strength it meant that No. 00, like all the rest, was kept flying the maximum number of hours machines and pilots could stand.

As the work speeded up the strain grew on pilots and machines, which also means on the mechanics. Some of the planes came home with bullet-holed fabrics, shot-through frames, and damaged engines. All the holes had to be patched, all the frames had to be mended, all the engines had to be repaired. The strain and pressure on a flimsy structure being hurtled through the air at speeds running from 100 to 200 miles per hour is bound to result in a certain amount of working loose of parts, stretching of stays, slackening of fabrics, give and take in nuts and bolts, yielding and easing of screws; and since the pilot's and the machine's life and the Squadron's efficiency alike depend on every one of the hundreds of parts in a machine's anatomy being taut and true, or free and easy-running, as the case may be, the mechanics began to find a full normal day's work merely in the overhauling and setting up of the machines, apart altogether from fight-damage repairs.

Two days before the Push began the mechanics put in a hard working day of fifteen hours out of the twenty-four; the day before the Push they started at 6 a.m. and finished at 1 a.m. next morning—and with the first patrols due to start out at dawn. But they finished with every machine trued to a hair-line, braced and strung to a perfection of rigidity, with engines running as sweet as oil, and giving their limit of revolutions without a hint of trouble, with every single item about them overhauled, examined, adjusted and tested as exhaustively and completely as if a life hung on the holding of every bolt, brace, and screw, the smooth, clean working of every plug, piston, and tappet—as, indeed, a life would hang that day.

The weather report of the day was not good, but a good half hour before dawn the mechanics had the machines out in line and the pilots were straggling out swaddled in huge leather coats, sheepskin-lined thigh boots, furred helmets and goggled masks. But before they arrived the mechanics had been out a full hour, putting the final touches to the machines, warming up the engines—for it was near enough to winter for the cold-weather nights to make an engine sulky and tricky to start—giving a last look round to everything.

The first two Flights went off before dawn, and the third an hour after them. The mechanics walked back into the empty hangars which, after the bustle of the last few days seemed curiously dead and desolate, and then to their waiting breakfasts.

For some of them the respite was short. Ten minutes after the last lot of machines had gone there was a shout for "A" Flight men. They hurried out to find the C.O. and the Flight Sergeant standing together watching a machine drive slowly up against the wind towards the 'drome. Plainly something was wrong with her; she had an air of struggling, of fighting for her life, of being faint and weary and almost beaten. It was hard to say what gave her this curious look of a ship with decks awash and on the point of foundering, of a boxer staggering about the ring and trying to keep his feet. It may have been the propeller running so slowly that it could be clearly seen, or the fact that she was losing height almost as fast as she was making way; but whatever it was, it was unmistakable.

As she drew near to the edge of the landing ground it was evident that it would be a toss-up whether she made it or touched ground in a patch of rough, uncleared field. The mechanics set off, running at top speed to where she was going to touch; the C.O. and the Flight Sergeant followed close behind them. They saw the pilot make one last effort to lift her and clear a sunk road and bank that ran along the edge of the landing ground. He lifted her nose, ... and she almost stalled and fell; he thrust her nose down again, ... and she hung, ... lurched, ... slid forward and in to the bank. Would she clear ... would she....

Then, in an instant, it was over. The wheels just caught the edge of the bank, her tail jerked up and her nose down, ... and the runners heard the splintering crash of her breaking under-carriage, of her "prop" hitting and shivering to matchwood, her fabrics ripping and tearing. She stood straight up on her nose, heeled over, and fell on her side with fresh noises of crackling, tearing, and splintering from her wrecked wings. Up to now the runners had thought of the machine, but in the instant of her hitting, their thoughts jumped to the pilot and—would he smash with her, or would the wreck catch fire? But before they reached the piled tangle of wood and fabric they saw a figure crawl out from under it, stand upright, and mechanically brush the dirt from his knees. They found he was untouched.

"Got a bullet in her engine somewhere, sir," he told the Major. "I caught a fair old dose from the machine-guns, and had the planes riddled; then this one got her, and I couldn't get my revs., and thought I'd better push her home. Poor old 'bus."

"Another one coming, sir," said the Flight Sergeant suddenly, and pointed to a machine whirling towards them at a thousand feet up. There was nothing wrong with this one, anyhow. She roared in over their heads, banked and swung, slid down smoothly and gracefully, touched and ran and slowed, and came to rest with the engine just running. It whirred up into speed again and brought her taxi-ing in towards the sheds and the mechanics running to meet her. The Major and the pilot, walking back towards the sheds, were talking of the show: "Something terriff., sir—never saw such a blaze of a barrage—and the place fair stiff with machine-guns. Yes, crowds of Huns—and ours—hardly pick a way without bumping—I put a good burst into one Albatross—didn't see——"

The Major interrupted: "Can you make out the letter—ah, there, 'K,'" as the machine, taxi-ing into the sheds, slewed, and they saw the big "K" on her side.

"'The Kiddie,'" said the pilot. "Morton's 'bus. Seemed to be running strong enough."

They quickened their pace, the Major with a growing fear that turned to certainty, as they saw men come from the sheds, clamber up on the machine, stoop over the pilot, and begin to lift him.

They found Morton hit in the foot and badly. But before he was well clear of the machine he was laughing and asking for a cigarette. "Yes, I stopped one, Major; but it doesn't feel too bad. Hullo, Solly, what's yours?"

"Engine hit, conked out, crashed her edge of the 'drome here," said Solly hurriedly. "I say, Major, can I take 'The Kiddie' and go back? I'm all right, and so is she—isn't she, Morton?"

"Better take a rest," said the Major. "After a crash like that——"

But Solly argued, protested so eagerly, that the Major gave in. The mechanics bustled and swarmed about "The Kiddie," filling the oil and petrol tanks, securing her light bombs on the racks fitted under her, replacing the expended rounds of machine-gun ammunition. And before Morton had finished his smoke or had the boot and sock cut from his foot, Solly was off. One might have imagined "The Kiddie" as eager as himself, her engine starting up at the first swing of the prop, roaring out in the deep, full-noted song that tells of perfect firing and smooth running. Solly ran her up, eased off, waved his hand to the two men standing holding the long cords of the chocks at her wheels. The chocks were jerked clear, "The Kiddie" roared up into her top notes again, gathered way, and moved out in a sweeping circle that brought her into the wind, steadied down, gathered speed again across the grass, lifted her tail, and raced another hundred yards, rose and hoicked straight up as if she were climbing a ladder. At a couple of hundred feet up she straightened out and shot away flat, and was off down wind like a bullet.

Then the "air activity" hit the Squadron on the ground. A tender and accompanying gang sped out to the crashed machine and set about the business of picking it up and bringing it home; telephone messages buzzed in and out of the Squadron office; another tender rolled out of the 'drome and started racing "all out" with a pilot bound for the Park, where a new machine would be handed over to replace the crash.

Before the crashed machine was in, the first lot out began to home to the 'drome. One by one they swept in, curved, slid down, and slanted smoothly on to the ground, and rolled over to the hangars. There was hardly one without a bullet-hole somewhere in her; there were some with scores. Planes were riddled, bracing and control wires cut, fuselage fabric and frames ripped and holed and cracked, propellers cleanly shot through. This was at 8 o'clock—and half of them were due to be up again at 1, and the others at 2. Every possible arrangement had been made for quick repairs and replacements, tools laid ready, spares brought out and placed to hand. The mechanics fell on the damaged machines like wolves on a sheepfold. Fuselages were ripped open, broken wires and controls torn out, badly damaged planes unshipped and slung aside, snapped and dangling bracing wires hurriedly unscrewed, suspected longerons and ribs stripped and bared for examination, holed or cracked propellers removed. In an hour anyone walking into the hangars might have thought he was in an airship-breaker's yard, and was looking at a collection almost fit for the scrap-heap. But at the appointed time the machines of the first Flight were ready, although it would take a decent-sized booklet to detail the nature and method of the repairs and replacements.

But every hole in a fabric had been patched, spare wing and tail planes had been shipped, new wires rove, damaged propellers replaced by new ones, fuselage covers laced up, guns examined and cleaned. At a quarter to one the pilots came from an early lunch and found their machines ready, fabrics whole and taut, wires and stays tight-strung and braced, engines tuned up and ready, everything examined and tried and tested, and pronounced safe and fit. And "The Kiddie," that had come in a full hour after the others, and had several bracing and control wires cut, and twenty-seven bullet marks to show for her two trips, was amongst the first to take off with the others.

As, one by one, the first Flight went up, the men were hard at work on the machines of the second, hoisting up tins of petrol and oil, and pouring them into the tanks, reloading the bomb-racks, packing away fresh stores of ammunition, trying and running up the engines.

At sharp two the second Flight took off, and at three the third (which had also brought home a miscellaneous assortment of injuries) followed them to the tick of time. But although all three Flights were out, the mechanics, with no faintest hope of a rest, set hastily about the business of mending and repairing those planes and parts which had been removed, and were now, or would be when they were done with, complete and ready spares.

They kept hard as they could go at it for a couple of hours, and then the first Flight began to drop in on them. One was missing—"crashed in No Man's Land"—another pilot reported, "Seemed to go down under control all right," and another was lost in Hunland.

The third Flight had even worse luck. Two were missing, nothing known of them, so apparently lost over the line, and another came circling back with her under-carriage swinging and twisting loose and hanging by a stay. On the ground they noticed the casualty, and, fearing the pilot might not be aware of the extent of the damage and try to land without calculating on it, they fired a light and signalled him.

But it was quickly evident from the caution of his manoeuvres that he knew, and he came down and pancaked as carefully as he could. He crashed, of course, but, as crashes go, not too badly. Everyone was watching him with bated breath. As he touched the ground—cr-r-rash—a tongue of flame licked and flickered, and instantly fouph it leaped in a thirty-foot gust of fire, dropped, and before the horrified watchers could move tongue or foot, blazed up again in a roaring, quivering pillar of fire. Then, as some scuffled for fire-extinguishers and others ran with vague and crazy ideas of dragging the pilot out, they saw a figure reel out from behind the blaze, throw himself down, and roll on the grass. He was burned about the hands and face, had a skin-deep cut across his brow, a broken little finger—nothing that a few dressings and a splint would not make as good as ever. He had leaped out as he landed.

His amazing escape brightened the shadow that would have lain on the Squadron Mess that night from the loss of the other pilots, and for the hour of dinner the talk ran free and mixed with jests and bursts of laughter. In the ante-room there was another half-hour's talk over the events of the day, a medley of air slang about revving, and Flaming Onions, and split-arming, and props, and mags., and Immelman Turns, and short bursts, and Hun-Huns, and conking, and all the rest. Then, about 9.30, the pilots began to drift off to bed, and at 10.30 the mess rooms were clear and the lights out.

But in the hangars, the armoury, the carpentry and machine shops, the electrics were at full blaze, the mechanics were hustling and bustling for dear life. It grew colder as the night wore on, and by midnight men who had been working in shirt-sleeves began to put on their jackets. By 2 a.m. they were shivering as they worked, especially those blue-lipped and stiff-fingered ones who had to stand still over a lathe or sit crouched, stitching and fumbling with numb fingers at fabric and tape and string. Again the hangars were filled with a welter of stripped and wrecked-looking outlines of machines, and all the apparent lumber of dismantled parts and waiting spares. About 3 and 4 a.m. tenders began to rumble in on their return from various errands, and at 5 orderlies came from the cook-house with dixies of hot tea. The Flight Sergeants confabbed and compared notes then and sent half the mechanics off to bed and set the other half to work again; and by 6 the machines were taking decently recognisable shape. And at half an hour before dawn again the machines of the first Flight were out and ready, with engines run up and warmed, and tanks full, and ammunition and bombs in place, waiting for the shivering pilots stumbling out to them in the dark. They were gone before the first blink of light paled the gun-flashes in the sky, and they were barely gone before there came dropping into the 'drome the pilots who had gone off the night before to fly in new machines to replace the wastage. A second Flight went at 9, and then the mechanics, who had turned in at 5.30, were turned out again and the others sent to bed. They had an even shorter spell of rest, because new machines somehow require an appalling amount of work and overhauling and tuning up before any self-respecting Squadron considers them fit to carry their pilots.

All that day the yesterday's performance was repeated, with the addition that parties had to be sent off in tenders to bring in machines that had made forced landings away from the 'drome and were unfit to fly home. The mechanics, dismissed for an hour at dinner-time and an hour at tea-time, spent about ten minutes over each meal, and the rest in sleep. They needed it, for that night they had no sleep at all, had to drive their work to the limit of their speed to get the machines ready for the pilots to take in the morning. That day there were more crashes, mild ones and complete write-offs, and it is hard to say which the weary mechanics loathed the most. The pilots had amazing luck. Man after man was shot down, but managed to glide back to our side of the lines, crash his machine, crawl out of the splintered wreckage, and make his way by devious routes back to the Squadron—to take another machine as soon as it was ready, and go out again next day.

For four days this sort of thing continued. In that time the mechanics averaged twenty and a half hours' driving hard work a day, the shop electrics were never out, the lorry-shop lathe, with relays running it never ceased to turn; the men ate their food at the benches as they worked, threw themselves down in corners of the hangars and under the benches, and snatched odd hours of sleep between a Flight going out and another coming in.

By the mercy, dud weather came on the fifth day, driving rain and blanketting mist, and the mechanics—no, not rested, but spurted again and cleared up the dÉbris of past days, repaired, refitted, and re-rigged their machines in readiness for the next call, whenever it might come. At the finish, about midnight of the fourth day, some of them had to be roused from sleeping as they stood or sat at their work; one man fell asleep as he stood working the forge bellows and tumbled backwards into a tub of icy water.

Then they reeled and stumbled to their beds, and again by the grace—since once asleep it is doubtful if mortal man could have wakened them—the sixth day was also dud, and the mechanics slept their fill, which on the average was somewhere about the round of the clock.

By then the fury of the battle assault had died down, the Squadron's duties were eased, and the mechanics dropped to a normal battle routine of fourteen or fifteen hours a day.

The Air Activity speeded up again after a few days of this, and from then on for another fortnight the men in the air were putting in two and three patrols a day and with some of the Artillery Observing machines in the air for four and four and a half hours at a time, while the men on the ground in the Squadrons were kept at full stretch and driving hard night and day to maintain their machines' efficiency. No. 00's mechanics did an average of nineteen to twenty hours work a day for fifteen days, and it is probable that if the full fact were known so, or nearly so, did the mechanics of most of the other Squadrons on that front. For, as it always does in prolonged fine weather and continued air work, the "air supremacy" became much more than a matter of the superiority of the fighters or fliers, dropped down to a race between the German mechanics and our own, their ability to stand the pace, to work the longest hours, to put in the best and the most work in the least time, to keep the most machines fit to take the air.

The workshops at Home play a bigger and much more important part in this struggle than ever they have known, and are in fact fighting their fight against the German shops just as much as their air men are fighting the Hun fliers. A constant and liberal supply of spares and parts needed for quick repair obviously cuts down the Squadron's work and better enables them to keep pace with the job, and time and again in this period the Squadron mechanics were forced to work long hours filing and hammering and turning and tinkering by hand to repair and improvise parts which should have been there ready to their hand. As the struggle ran on it became plainer day by day that our men were gaining the upper hand, not only in the fighting—they can always do that—but in the maintenance of machines in the air. The number of ours dropped, perhaps, but the Huns' dropped faster and faster, until our patrols were entirely "top dog." The pilots will be the first to admit the part their mechanics played in this victory.

Through all this strenuous time "The Kiddie," for instance, played her full part. Time and again her pilot brought her in riddled with bullets, with so many controls and flying-and landing-wires and struts cut through, that it was only because she was in the first place well and truly built, and in the second place, so keenly and carefully looked after, that Solly was able to nurse her back and land her on the 'drome. And always, no matter how badly damaged she came in, she was stripped, overhauled, repaired, and ready for action when the time came round for her next patrol; and always the work was done so thoroughly and well that she went out as good, as reliable, as fit to fly for her life, as any 'bus could be.

In the first week of the show, which was the most strenuous period just described, Solly Colquhoun got a Military Cross for his share of the show, and on first receiving word of it the Major sent for him to come to the office, and gave him the news and his congratulations.

"May I borrow the message, sir?" said Solly Colquhoun. "I'll bring it back in five minutes."

The Major gave him the telegram.

"Off you go," he said laughingly. "Off to raise the mess, I suppose. Get along. I'll be over to wet the Cross with you in a minute. Tell the Mess Sergeant to get the fizz ready that I had in."

But Solly had not gone to rouse the mess. He went at a hard trot straight to the Flight hangars.

"Flight," he yelled as he neared them. "Fli-i-ght! Where's the Flight Sergeant? Oh, here, Flight—I want you and my rigger and my fitter. Fetch them quick."

They came swearing under their breaths. "The poor old 'Kiddie' for the air again," said the rigger. "Done her whack this trip, hasn't she?" returned the fitter.

"Look here," said Solly abruptly, hardly waiting for them to come to a halt before him. "Just read that wire, will you?... I brought it straight here. You're the first in the Squadron to know. I wanted you to be, and I wanted just to say thank you to you fellows for getting me this Cross. I know what 'Kiddie' has stood up to, and why. I know what you did, ... and ... well, thank you."

He shook hands awkwardly but very heartily while the men stammered congratulations and disclaimers of any reason for thanks. "Must beetle off," said Solly. "Promised to take this paper over. Tell the other men, will you? A Military Cross for our Flight. And thank you again."

He turned to hurry out, but, passing "The Kiddie," stabled there with her fore-end swathed and blanketted, her sides sleek and glossy and shining, taut and trim, spotless and speckless as the day she came from her makers, he halted and ran a fondling hand down her rounded back.

"Thank you too, 'Kiddie,'" he said, nodded to the Sergeant, "I got a good old 'bus, Flight," turned, and ran off.

"A d——n good 'bus," said the Sergeant, "and a d—— n good man flying her."