The army behind the army

At about the time that the German War Lord, resplendent in the eagle-crowned helmet and silver cuirass of the Guard Cuirassiers, was haranguing in sonorous phrases the punitive expedition which was about to depart for China, two young mechanics in greasy overalls were at work in an obscure machine-shop in an Ohio city on a strange invention which was destined to prove a far more potent weapon than the Kaiser’s boasted “shining sword.” Now it is certain that at this period the All Highest had never heard of these young mechanics, and though they, of course, had heard of him, I imagine that to the accounts of his spectacular doings which appeared almost daily in the newspapers they paid about as much attention as they did to the gaudy lithographs on the local bill-boards which heralded the annual visit of the circus. Yet, could William of Hohenzollern have looked a dozen years into the future, he would have seen that these two silent, earnest, unassuming brothers from the Middle Western town were destined to have a profounder effect on the future of the great empire which he ruled, and, indeed, on the history of the world, than he and all the princes, soldiers, and statesmen who surrounded him.

Notwithstanding the jibes and forebodings of the professional critics, the ponderous sarcasms of senators and congressmen, and the sensational stories of failure which have appeared in the press, there are few more brilliant chapters in our national history than the story of the airplane. Do you realize, I wonder, that the airplane is the development of barely a decade? Had a life-insurance company, ten years ago, learned that one of its policy-holders was planning to take a ride in a “flying-machine,” it would promptly have cancelled his policy. Yet to-day planes carrying the air-post between the cities of the Eastern seaboard go booming down the air-lanes as regularly as express-trains and without attracting much more attention.

The story of the airplane, so far as its relation to the American Army is concerned, begins on the little flying-field of Fort Myer, on the Virginia side of the Potomac, opposite Washington. In the late winter of 1907 the Signal Corps had issued an advertisement and specifications for a heavier-than-air flying-machine, the chief requirement being that it must remain in the air for an hour without landing. Most of us will remember the world-wide interest which was aroused by this promised realization of the dream of the ages. During the trials the eyes of the world were centred on the parade-ground at Fort Myer. The President and the members of his cabinet were in frequent attendance and even Congress adjourned when it was announced that a flight would take place. The story of how the strange contrivance, looking like a combination of a box-kite, a baby-carriage, and a windmill, which had been brought on from Dayton by the two sober-faced brothers, was trundled out onto the field; how, after skimming along the ground, it rose into the air as gracefully as a swallow, and how, after fulfilling every condition imposed by the War Department, the first machine was purchased by the government, needs no elaboration here. The most amazing feature of the affair, barring only the performance of the airplane itself, was the fact that during the eight years following the demonstration at Fort Myer the entire appropriations by the government for military aeronautics amounted to less than a million dollars. Think of it, my friends! With the secret of aerial navigation in our hands—a secret which had been sought for by scientists all down the ages—Congress devoted less money to its development during the first eight years than it spent on many a post-office or government building. But the astounding apathy which characterized our attitude toward this epoch-making invention did not extend to the great European nations. They, always seeking to obtain military superiority, instantly recognized the significance and the potentialities of those early flights at Fort Myer. France, in particular, during the next few years making marked advances in aircraft design and construction. Thus it came about that when the war-cloud burst over Europe in the summer of 1914 the United States, where the airplane had its birth and where it had first demonstrated its practicability, possessed only a few decrepit and almost obsolete training-machines, while our fliers could almost have been numbered on the fingers of one’s two hands. Whose was the fault for this deplorable and inexcusable condition? A certain amount of blame undeniably attaches to the army, for in those days many of our higher officers were graduates of the old Indian-fighting school, who regarded with doubt and scepticism the claim that these new-fangled flying-machines could have any real military value. I think, however, that the real cause of the neglect in developing the airplane could have been found in the building with the great white dome which stands at the far end of Pennsylvania Avenue.

As a direct consequence of our systematic discouragement of airplane development, when we entered the war there was no such thing as an aviation industry in the United States and the number of aeronautical engineers and designers was so small as to be practically negligible. In this respect the problem of developing an air-fleet was unique. The United States had built ships before, it had manufactured cannon, rifles, ammunition, it had fed and clothed and housed armies, and it had at its command thousands of men qualified to do these things and do them well, but, barring a handful of experts in Dayton and Buffalo, there was no one in this country with experience in the designing or building of either training or fighting planes. In short, the government was faced with the problem not merely of developing a new industry, but of creating it.

In April, 1917, there were being built in the United States only four makes of aircraft engines that were sufficiently developed to be of any military value, and even these were useful only for primary training. We had no engines suited for service on the battle-front, or, indeed, even for the advanced training of pilots. Though the largest engine manufactured in the United States at this time developed about 220 horse-power, it had not measured up to the exacting requirements of combat. The other American-built engines ranged from 90 to 135 horse-power. It being evident, therefore, that the existing American engines could be used only for purposes of preliminary instruction, it was accordingly decided that their further manufacture should be limited to the training requirements. As a result of this decision, by far the greater part of the primary training of pilots has been conducted with the Curtis 90 horse-power engine, a quantity production of which was obtained early in the war, this engine being particularly valuable owing to the very satisfactory training-plane which had been designed around it. Considerable use was also made of the Hall-Scott 100 horse-power engine until the Curtiss motor could be manufactured in sufficient numbers to meet all demands for primary training. Two European engines, the Gnome 100 horse-power and the Hispano-Suiza 150 horse-power, were also being put into production in the United States at this time. These engines represented the highest product of European design and engineering skill, and were in a perfected and standardized state, at least according to European ideas, when their manufacture was undertaken in this country. But the changes involved in adapting them to manufacture by American methods required so much time, and the advances made in aeronautical engineering were so rapid, that before they could be produced in sufficient numbers they were almost obsolete for service on the front. These two engines were, however, of unquestioned value for advanced training purposes, the Hispano-Suiza in particular playing an important part in this work. Later another European engine, the 80 horse-power Rhone, was also put into production.

One of the serious mistakes into which the Allies had fallen at the time the United States entered the war was the development of such a multiplicity of types of engines and planes that it was impossible to have a large number of any one of them. Indeed, by the spring of 1917, there were almost as many types of planes skimming over the Western Front as there were types of motor-cars skimming over American roads. As a direct consequence of this condition, the trained personnel had grown to such proportions that it was estimated that from thirty to fifty men were required on the ground to keep each plane in the air. It was obvious, therefore, that unless this large number of trained attendants could be materially reduced, it would be hopeless to expect to put thousands of fighting planes into the air within a reasonable time, for, on this basis, 1,000 planes would require from 30,000 to 50,000 men to take care of them. It was realized, moreover, that copies of foreign designs could not be made available in time to answer the insistent demand that America should put on the front an air force of overwhelming proportions.

Although, immediately upon the declaration of war, an aircraft commission had been sent to Europe for the purpose of gathering first-hand information, public sentiment would not have permitted the government to sit idly by and wait with folded hands for this commission to make its report. What the country demanded was action with a capital A. Now it is not generally known, perhaps, that, instead of engines being designed for certain types of aircraft, the most successful airplanes are designed around specific engines. And, as the development of the engine requires the greatest expenditure of effort and time, some one suggested that, instead of waiting for the members of the commission to come home and tell about the European engines they had seen, to manufacture which under American conditions might well prove impracticable, an all-American engine, combining the best features of the various European types but particularly adapted for manufacture under domestic conditions, be designed by the best engineering talent in the country and immediately placed in production. At a meeting of representatives of the Signal Corps—which then had charge of military aeronautics—and the Aircraft Production Board it was decided to put this suggestion into immediate execution, at the same time purchasing in Europe whatever equipment might be available in order to tide over the period while the all-American engine was being put into production.

At noon on May 29, Lieutenant-Colonel J. G. Vincent and Lieutenant-Colonel E. J. Hall, two of the most brilliant automotive engineers in America, shut themselves in a room of the New Willard Hotel in Washington. When they left that room again on the afternoon of the 31st, though haggard from lack of sleep, they had in their hands the completed assembly drawings of an entirely new airplane engine. Thus was born the famous Liberty engine, about which hundreds of speeches have been made and thousands of columns have been written in scepticism, in criticism, and in praise. As the result of the enthusiastic co-operation of some ten manufacturers, each of whom produced those parts for which his factory was best fitted, the first Liberty, an 8-cylinder, was built in thirty days. The first 12-cylinder engine completed its official endurance test eighty-two days from the time the order for samples was given, the unqualified success of this test removing the Liberty from the realm of experimentation to that of established reputation. In just one year from the day that Lieutenant-Colonels Hall and Vincent pushed the thumb-tacks into their drawing-boards in the hotel room, 1,100 Liberty “twelves” were produced—a remarkable illustration of the ability and ingenuity of American engineers and the energy and resourcefulness of American manufacturers. Thanks to the energetic co-operation of many manufacturers, more than 14,000 Liberty engines had been completed when the Armistice was signed. There are few finer passages in the history of America’s participation in the war than the story of how our manufacturers put aside their private interests and their commercial rivalries and threw themselves and their organizations, heart and soul, into the work of building an airplane that would make America mistress of the skies.

When the signing of the Armistice brought our efforts to an abrupt conclusion, there had been developed, tested, and adopted by the army four types of airplanes, production of which would have started early in 1919. They were the Lepere, or L. U. S. A. C. II, a two-seated fighting-plane equipped with a Liberty engine; the U. S. De Havilland 9-A, a day-bombing and reconnaissance plane also fitted with the Liberty engine; the huge Martin bomber, with a gross weight of nearly 5 tons, driven by two Liberty engines; and the Loening, a two-seated combat plane fitted with the 300 horse-power Hispano-Suiza engine.

A striking illustration of the new problems and extraordinary ramifications incident to this great new industry which so suddenly came into existence in the United States is the fact that it was found necessary to despatch an agricultural expert post-haste to India to purchase enormous quantities of castor-beans, as it was at first believed that castor-oil was the only satisfactory lubricant for these new types of high-speed, high-power engines. India’s stock of castor-beans being quickly exhausted by the immensity of our demands, more than 100,000 acres of the bean were planted in the United States. Meanwhile, research work with mineral oils was carried on intensively, a lubricant eventually being developed which proved satisfactory in practically every airplane engine except the rotary type, for which castor-oil is still preferred.

But the aircraft problem was by no means solved with the development and production of the Liberty engine. Far from it. To build airplanes requires wood; the best timber in the world is none too good; and of suitable timber there was a comparatively limited supply. The best wood known for airplane construction is the Sitka spruce, which combines the required qualities of strength, resiliency, and lightness. This spruce grows mostly in the Pacific Northwest, along the tide-lands of Washington and Oregon, at a low elevation. But not all the planes were built of spruce, fir, as it grows in the Northwest, being largely used for the heavier wing-beams. Port Orford cedar was eagerly utilized whenever it could be obtained. It is of somewhat smaller growth than spruce or fir, but a straighter-grained wood, harder and more dense than either of the others. Of this splendid wood there is, however, only a comparatively small quantity, 2,000,000,000 feet, perhaps, anywhere in the world, mostly near Coos Bay, on the coast of Oregon. Being less affected by water than any of the other woods, it was reserved for use in seaplanes. The government commandeered the entire supply of Port Orford cedar for aircraft production, but released it upon the signing of the armistice.

There is plenty of suitable airplane timber—spruce, cedar, and fir—in the Far Nor’west—miles and miles and miles of it. The mountain-slopes are as solid a black with the evergreens as though a giant had painted them with soot. “Massed in their black battalions stand the bleak, barbarian pines.” Foolish men have tried to destroy these forests. Twenty years ago a colony of Poles settled amid the virgin forests of the Olympic Peninsula—a portion of the United States which to this day remains virtually unexplored. Timber was not worth a dollar a million feet then. On the chance that the ground might be tilled if the timber could be cleared off, the settlers started a fire that burned over ten square miles and destroyed timber which, at prevailing prices, would be worth close to half a million dollars. The great area of blackened waste which remains is still known as “The Polander Burn.”

Now spruce, curiously enough, had not been considered a valuable wood for the ordinary lumber trade; the lumbermen held it a doubtful asset that was hardly worth the cutting. As a result of this condition, the commercial supply was neither large enough nor well enough selected and prepared to meet our aircraft requirements when the declaration of war suddenly made it one of the most desired and most valuable woods in existence. Thus it came about that, the lumbermen being unable to supply the demand, the army had to go instantly into the business of producing this wood in theretofore undreamed-of quantities. The work of getting out the spruce fell, rather oddly, to the men who had been among the first to volunteer for extrahazardous service in France. Before the war, when airplanes were looked on merely as toys of the rich, the supervision of military aeronautics was assigned to the Signal Corps, on the assumption that if flying had any part in warfare it would probably be that of signalling, for which reason, and the more potent one that no other branch of the service knew what to do with it, it had to be wished on some one. And of all the branches of the army, possibly none save the Flying Section of the Signal Corps—as the Air Service was then known—had a more adventurous and devil-may-care personnel. The Signal Corps made its original appeal to the men who wanted to get out and do things: to be in front, to wave the little red-and-white flags under shell-fire, to sound the long yell, to see the enemy first, to be the eyes and ears and nerves of the whole army. But, as I have already explained, the army had to have the spruce in order to carry out its aviation programme, and aviation was under the Signal Corps, and it was from the Signal Corps, therefore, that the men were drawn to go out to the Northwest and get the spruce. Thus it came about that the boys who enlisted at the very beginning in order that they might have the danger and excitement of laying the field telegraphs and telephones, of dashing madly along shell-swept roads on roaring motorcycles, of wig-wagging and semaphoring word of the enemy’s movements from in front of the armies, were shipped westward instead of eastward, were given axes instead of Enfields and peaveys instead of pistols, and fought their share of the war in the gloomy depths of the primeval forest, or on the logging railroads and in the sawmills which they built in bitter cold and driving rain.

Labor conditions were undeniably bad in the Northwest at the beginning of the war. There is an old proverb that “A farm lease is a conspiracy on the part of the tenant and the absentee landlord to rob the land.” Lumbering was almost as bad. The owners were avaricious and arrogant, the men stubborn and defiant. The owners would not make camp improvements because “the men would not stay on the job,” and the men would not stay because “the owners didn’t make things decent.” And, to make things worse, the paid German propaganda was rampant, unchecked in the woods, for the Wilhelmstrasse fully realized how vital it was to cripple the American air programme. Germany knew better than we did the war possibilities of the Pacific Northwest. She couldn’t buy spruce there for her planes, but she could mobilize her spies and trouble-makers and hinder the production for and the delivery of spruce to the United States and her allies. And she did her worst. Some day there will be told the story, the “inside” story, of the campaign waged in the Great Woods by the secret forces of Germany—a campaign consisting of strikes, I. W. W. demonstrations, forest-fires, railway wrecks, dynamited bridges, damaged machinery, infernal machines, shootings, systematic intimidation, and all the other deviltries of a vicious and unscrupulous enemy. The spies and secret agents which Germany planted in the forests of the Northwest formed a part of the vast army of which the Kaiser boasted to Ambassador Gerard. But the Hun made a miscalculation. There were not enough spies; there were too many Americans.

The War Department has rarely shown greater wisdom than when it gave a colonel’s commission to Brice P. Disque, an ex-captain of Regulars who had left the army to accept the wardenship of the Michigan State Prison, and put him in charge of spruce production. Captain Disque had his blanket-roll packed and aboard ship for service in France when he was called to Washington, just as the transport was setting sail, and ordered to go to the Northwest and investigate lumbering conditions. His report showed that the right man had been found to direct the Titanic job of getting out the spruce; he was commissioned a colonel and later a brigadier-general, and the story of the spruce production tells the rest.

To the tact and vision of General Disque is due the creation of that remarkable organization known as the Loyal Legion of Loggers and Lumbermen, an association conceived to bring capital and labor together in one mighty machine driven solely by patriotism. Under the inspiration thus provided, both sides agreed to submit their differences to the United States Army, as represented in the person of General Disque, as final arbiter. The eight-hour day was agreed to; camp sanitation and better living conditions of every kind were demanded; a uniformly liberal wage-scale for all classes of labor was adopted; a standard mess was arranged to check the inordinate waste of food in the lumber-camps; the owners were given profitable prices for their output under the new conditions, and the small men were assured of receiving a square deal from their powerful corporate rivals. Some of these questions were settled through regular military channels, but most of them through the medium of the L. L. L. L. Once a matter could be shown to be reasonable and fair to every one concerned, it was officially adopted, as by a majority vote, and business as well as patriotic reasons demanded that every one should cheerfully acquiesce in the decision. The Loyal Legion works—for it has been made permanent—through its local assemblies; any local disagreement is taken to the district council—which is formed from local representatives of both employer and employees, there being eight of these district councils in the Coast Division and four in the Inland Empire. Any question which cannot be settled by a district council goes to the Central Council, composed of one employer and one employee from each district; while General Disque, as the head of the Legion, has been the final arbitrator in such questions as the Central Council could not settle. Since this plan was definitely adopted, however, so strong a spirit of patriotic fairness has been developed on both sides that nothing has gone to him for settlement or revision. Nothing could more strongly emphasize the success of the Legion, which now has a membership of nearly 130,000, than the fact that at a mass convention, held shortly after the signing of the Armistice, at which more than 900 local councils were represented, it was voted almost unanimously to perpetuate the organization, to continue the publication of its official bulletin, and to invite General Disque to continue as the Legion’s head. Were the people of the Pacific Northwest to receive no other reward for their sacrifices in the war, they have reason to feel amply repaid by the creation of the Loyal Legion and the resultant ending of the long-standing feud between capital and labor, the expulsion of the I. W. W.’s and similar discordant and dangerous elements, the betterment of working and living conditions for the lumbermen, and the commencement of an era of peace and prosperity in the Great Woods.

Unless you have been in the Northwest during the rainy season you can have no adequate conception of the difficulties under which the spruce squadrons labored. The coastal districts of Oregon and Washington have one of the heaviest rainfalls recorded anywhere on earth. Unkind people have said of the Pacific Northwest that it has but two seasons—the rainy season and August. But that is an exaggeration. The local newspapers alternately boast of and apologize for the reputed 180 inches, or 15 feet, of annual precipitation. With that as a basis for one’s calculations, the old man who sold the town site of Simescarey, the terminus of the spruce road which the government has built into the Olympic Peninsula, has had 450 feet of water descend upon his head—for the inhabitants of that region scorn umbrellas—in the thirty years that he has resided there. After a winter spent in the Northwest—and having passed one there, I know whereof I speak—one might easily believe that the sentry at an Oregon spruce-camp was not joking when he came in to the commanding officer to report the damages done by the rain.

“Sir,” he apologized, “I don’t like to be a pessimist, but things ain’t going right to-day. Most of the fish in the lake are dead since last night’s rain. The lake raised so fast that some of ’em got beyond their depth and was just naturally drowned; the rest couldn’t swim up fast enough, and bein’ surface fish and not used to much depth, their bladders busted and there ain’t a fit fish left in the whole bunch. Every duck but one is dead, too; the rain beat their heads into a mush—all but the one that got caught in a steel trap set for a muskrat and that saved his life—he stayed under water where it was dry. Believe me, sir, that was the wettest rain last night I ever see.”

Because, as I have already explained, the lumbermen did not consider spruce a profitable wood to handle, few of the spruce forests had been penetrated by railroads. So Disque and his Legionaries set out to build railways themselves—13 lines with more than 300 miles of trackage. The forests tapped by these new lines and their branches have, it is estimated, an ultimate production of 33,000,000,000 feet of lumber, a quantity almost beyond the comprehension of the human brain. In order to visualize it, it must be translated into commonplace, every-day terms. Let us assume that it requires 20,000 feet of lumber to build an average 5 or 6 room house. Taking this as a basis, the railways built by Disque and his spruce squadrons have brought within the reach of commerce enough timber to build almost 2,000,000 of these comfortable American homes, with sufficient waste wood to keep them heated for a generation. When the war ended, 174,000,000 feet of aircraft lumber had been cut and shipped—enough to build dwellings for the inhabitants of a good-sized city.

The government planned to have all the airplane stock from the Northwest cut at the one great cut-up plant at Vancouver, near Portland. This huge mill, the largest in the world, was built by the army in forty-five days and has handled more than a million and a half feet of lumber in twenty-four hours. But with the extension of the airplane programme, whereby the Spruce Division was called upon to furnish stock for all the Allies, more capacity was required and three other great plants of almost equal size were planned, one being ready for opening, one almost completed, and one projected when the Armistice was signed. These four huge mills would, it is estimated, have furnished the United States and her allies with close to 100,000,000 feet of airplane lumber a month.

The silent, peaceful forests of the Northwest seemed separated from the war by a million miles, a score of generations. But when the word was flashed from Washington to Disque to “Go ahead,” the primeval silence of the woods was suddenly shattered by a million bellowing echoes of battle. The war had come to America. Almost overnight the battle-front moved 6,000 miles westward—from the forests of the Argonne to the forests of Oregon. The trucks were brought in—endless caravans of grunting, straining monsters; the soldiers came, 30,000 in all; the loggers, graders, hard-rock men, sawyers, surveyors, engineers; the pile-drivers, the donkey-engines, the steam-shovels perched on wheels, the train-loads of food and tools and powder; the patient, sweating horses and the creaking wagons, thousands upon thousands of them. The wood roads were black with traffic; they fairly smoked with the fierce fight for speed. The highways were dust in the early fall, where the 5 or 15 ton loads ground the roads to powder. Then the wet weather came—fogs, mists, drizzles, showers, floods—the rainy season that grows the incomparable forests of the Northwest.

They splashed through it all, soldiers and Legionaries alike; they waded, they swam, they shivered and swore, and beat their hands over the brush fires—but the stream of supplies never stopped nor checked. The railway gangs, following close on the heels of the axemen, laid their twin lines of steel through the dripping forest faster than Kitchener laid down his desert railway to Khartoum, the locomotives crawling one mile, two miles, deeper into the wilderness each night. Night and day the forest trails were busy. Shuttling back and forth, loaded both ways with materials and men, teams and trucks and trains struggled for speed. Headlights, lanterns, shouted warnings, guided the night traffic along the sombre, shut-in ways. Clankings, clatterings, gasoline coughings, the honk of horns and the hoot of locomotives filled the air. The silent forest became a bedlam of sound, of action.

The spruce! The fir! The wings of victory! Berlin heard it, saw it first. The splitting blasts that showered the forest lakes with stones, the shouting, heaving din of the construction-camps, the crash of the trees as they fell before the axe and saw of the woodsmen, the whine of the cables through the sheaves as the huge logs were snaked into position for loading, the rumble and roar of the heavy-laden log-trains, the shriek of the giant saws in the mills—all these sounds fell upon the listening ears at German Great Headquarters with a growing menace, as ominous as the tattoo of the machine-guns, as the thunderous blast of the great Allied cannon, as the victorious cheers of the charging Yanks. They meant that the spruce was coming! The planes were coming! A few months more and the boasted Hindenburg Line would be a joke. The Germans knew that they could not build trenches in the clouds. That was the real reason why they were attacked by yellow fever in the fall of 1918.

The engines and the planes themselves being in production, the next problem to be solved by the War Department was to provide our new aerial navy with armament in the form of machine-guns. Fighting in the air, it should be remembered, is entirely a development of the Great War, the adaptation of machine-guns for airplane use having practically all taken place since 1914. Though the records show that a machine-gun was successfully fired from an airplane in this country in 1912, and though the French had a few heavy planes fitted with mitrailleuses at the outbreak of the war, it was not until 1915 that machine-guns were carried by planes on active service. Prior to that time aviators depended on service and automatic rifles, pistols, shotguns shooting large shot held together by wires—miniature editions of the chain-shot used by early sea-fighters—and also carried darts and grenades to drop on the enemy. As a matter of fact, in one of the first aerial combats of the war, which took place on the Eastern Front between a Russian aviator and an Austrian, weapons were not used at all. The Russian determined to wreck his adversary and, in pursuance of this plan, so manœuvred his plane that the tips of his wings were just beneath the wings of the Austrian. He then suddenly elevated that end of his plane, hoping to upset the Austrian, but the result was that both machines collided and fell to the ground. Major Eric T. Bradley, formerly in the British Army but now an officer of the American Air Service, tells of having flown over the lines in 1915 armed with a twelve-gauge double-barrel shotgun loaded with buckshot tied together with wire, which swished through the air like the lash of a whip and occasionally hit something—usually by chance.

The development of methods for controlling machine-guns so that they can be fired through the area traversed by the propeller has had a vast effect on aerial combat, and an understanding of the problems involved is necessary in order to appreciate the difficulties which had to be overcome. The various devices which have been developed for controlling the fire of a machine-gun so as to cause the bullets to miss the blades of the propeller are commonly known as synchronizing or interrupter gears. These terms are, however, somewhat inaccurate, as it is only occasionally that the speed of the propeller is equal to the rate of fire of the gun, which is the condition of synchronization; moreover, the gun is not interrupted, but is caused to fire at the proper moment so that the bullet will miss the propeller-blade. “Gun control” would be a more descriptive name for the device.

Tractor airplanes—those which have the engine and propeller in front—were early found to be better suited to combat work than planes of the “pusher” type, which have the propeller behind, because they possess greater manœuvring powers and are better able to defend themselves. With these planes was developed the fixed aircraft machine-gun. This gun is fixed rigidly to the plane, pointing straight ahead, parallel to the line of flight. The first fixed guns were mounted on the upper plane so as to shoot over the arc described by the propeller, but these were not satisfactory owing to the difficulty in reloading the gun. To overcome this very obvious disadvantage the gun was lowered, which brought its line of fire inside the arc described by the propeller blades. Thus arose the difficulty caused by shooting into the propeller, to solve which countless experiments were made and numerous expedients tried. At first the blades were armored at the points where the bullets would strike, with steel of a shape calculated to cause the bullets to glance off, but this system was never satisfactory. Then the experiment was tried of wrapping the propeller with linen to keep it from splintering, as it was found that several bullets could be fired through a propeller thus treated without causing it to break. Throughout the summer of 1915 all of the Nieuport fighting-planes used by the French were fitted with fixed guns shooting through the propeller—if a bullet hit the propeller it either went through it or it wrecked it.

There is considerable disagreement as to who invented the device for controlling the fire of a machine-gun so as not to strike the blade of the propeller, but it is admitted that the Germans were the first to make any extensive use of it, introducing it on the Fokker monoplanes, which caused so much damage on the Western Front in 1915. Shortly thereafter the Allies adopted similar devices. When the United States entered the war neither the Ordnance Department nor the Aviation Section of the Signal Corps had had any experience worthy of the name with aircraft guns. And if they were ill-informed on the subject of guns, they were appallingly ignorant on the subject of gun controls. A few months of study and experiments served to materially increase the War Department’s knowledge along these lines, however, and by the time the planes were ready to receive the guns we had adopted a device known as the Constantinisco control. I should explain, perhaps, that there are two distinct types of gun control, both of which were in use when hostilities ceased. One is hydraulic, the other mechanical. The operation of both types is somewhat similar. In each case a cam mounted on the shaft of the engine actuates a plunger which in turn operates the rest of the mechanism. In the mechanical gun control the impulse of the cam is transmitted to the gun through a series of rods, causing the gun to fire at the exact moment when there is no propeller-blade in front of the muzzle. In the hydraulic type the impulse of the cam is transmitted to the gun through a system of copper tubes containing oil under high pressure. The hydraulic control, known as the Constantinisco, was adopted for use on American planes, particularly the De Havilland 4, which carries two fixed Marlins, each firing at the rate of 650 shots a minute. By employing the maximum rate of fire, 1,300 shots could be fired in a minute through the blades of the propeller, which would make 1,600 revolutions in the same space of time—without the blades being struck by a single bullet.

A machine-gun intended for aerial use must be absolutely reliable in operation. If a gun jams on the ground there is usually time to overhaul it or to replace it. Not so in the air. There a jam or a malfunction is almost certain to prove disastrous, if not fatal, to the gunner, who is left completely at the mercy of his adversary. An aircraft gun must also function properly in any position in which it is likely to be placed by the manœuvres of the plane. Likewise, an intensely high rate of fire is essential. For groundwork 500 shots per minute is reckoned as sufficient for the machine-gun, for a higher rate of fire would only result in several bullets hitting the same man. But a considerably higher rate of fire—up to 1,000 shots a minute, in fact—is demanded of aircraft guns, this being necessitated by the great speed at which airplanes move. The gunner, remember, can train on his target for only a few seconds, sometimes for only a fraction of a second, at a time, and it is essential, therefore, that he should have at his command the greatest possible volume of fire. Do you appreciate that, were an airplane flying parallel to, say, a high board fence, at a speed of 100 miles an hour, and shooting at right angles at that fence with a gun firing 880 shots a minute, the bullet-marks on the fence would be ten feet apart?

Single-seater machines carry only fixed guns, which are mounted with the barrel parallel to the axis of the airplane. These guns, which are synchronized so as to shoot through the propeller, are put into action by a trigger on the “joy-stick” of the plane and are aimed by pointing the entire airplane at the enemy. Flexible guns are used only on two-place machines, being operated by the observer or gunner. They are carried on the Universal mount, which permits of the gun being pointed in any direction. All of the flexible aircraft guns used by the Allies were based on the principle of the Lewis gun, the invention of a retired American army officer, Colonel Isaac Lewis. The chief difference between the ground and aircraft models is that in the latter the cooling radiator is eliminated, as aircraft guns are never fired continuously for any length of time.

When the United States entered the war the Vickers was the only type of fixed gun in use on either English or French planes and was used on all the planes which General Pershing bought in France. When the Equipment Division of the Signal Corps faced the machine-gun situation in September, 1917, it was alarmed to find that the entire production of Vickers in the United States had already been contracted for to supply the imperative requirements of the infantry. There was another gun on the market at this time, however—the Marlin—and toward its development for aircraft use the officers of the Signal Corps bent all their energies. Though the Marlin was adopted in the face of violent opposition, it resulted in providing sufficient fixed guns to arm the American planes, the wisdom of the action being proved by the fact that up to the time of the Armistice no other fixed guns were ready for delivery. The Marlin has been adapted to all American-built planes which carry fixed or synchronized guns, over 37,000 having been produced up to December, 1918. This gun shoots .30-calibre ammunition at the rate of 600 to 650 shots a minute and is fed from a belt of the disintegrating metal-link type. In December, 1917, the first order was placed for Lewis aircraft guns, over 39,000 of them being delivered to the American Air Service within the following twelvemonth. A notable improvement in the aircraft model of the Lewis gun was an increase in the depth of the magazine pan, so that each magazine holds 97 cartridges instead of 47 as previously. The Browning aircraft machine-gun was just coming into production when the war ended. This weapon embodies the best features of every known machine-gun and would probably have replaced all other types in use. It is a belt-fed gun of the recoil type—both the Marlin and Lewis are gas-operated—is as near fool-proof as a machine-gun can be made, and has the amazing rate of fire of 950 shots a minute. Of it the inventor is said to have remarked: “If it had four more parts it could play a tune; if it had seven more parts it could talk.”

The ammunition for fixed aircraft guns, such as the Marlin and Browning, is carried in belts containing a maximum of 500 rounds. In the earlier days of the war these belts were of woven web, but it was found that taking care of them, when empty, in the limited space of the fuselage, was always a source of annoyance and not infrequently a source of danger to the aviator. To remedy this a belt was designed and furnished to the American Expeditionary Forces which consisted of small metallic links held together by the cartridges themselves. As the gun fires, the links drop apart, chutes being provided so that they fall clear of the airplane. Another minor though interesting feature of aircraft armament is the small electric heater which is now provided for the purpose of keeping the gun warm and thus preventing the oil from congealing in high altitudes.

Efforts to make the bursts of fire from aircraft guns of maximum effectiveness have led to the development of three distinct types of ammunition—tracer, armor-piercing, and incendiary. The tracer type of ammunition was developed to assist the gunner in correcting his aim, and is equally useful by night or day, as the course of the bullet can be traced by a trail of white smoke in the daytime and by a bright spark at night. Armor-piercing ammunition has a projectile consisting of a hard steel core with a soft nickel casing. The object of this ammunition, as its name implies, is to pierce any of the metallic parts of an enemy plane, particularly the gasoline-tanks or the engine, the soft nickel casing acting as a lubricant and preventing the steel core from glancing off. Incendiary ammunition is loaded with yellow phosphorus. When the cartridge is fired the rifling in the barrel of the machine-gun opens a small hole in the case of the projectile, thus permitting the phosphorus to come in contact with the air, whereupon it immediately ignites and sets fire to any inflammable part of a plane which it may hit. It is customary to load the belts or pans of aircraft machine-guns with these three types of special ammunition in a certain sequence, depending upon the notions of the pilot himself. A sequence commonly used was, first, the tracer cartridge, which assisted the gunner in correcting his aim; next, two or three armor-piercing cartridges, in the hope that they would pierce the enemy’s gasoline-tank or damage his engine; and then one or two incendiary cartridges, which if the gasoline-tank was pierced would ignite the leaking gasoline and set fire to the machine. This sequence was continued throughout the loading of the belt or pan.

Another branch of sky warfare which was being rapidly developed was aerial bombing. Though bombs of a sort were used by Italian aviators against the Arabs during the Libyan campaign, and by American soldiers of fortune serving with the Villista forces in northern Mexico, these attempts were so amateurish and ineffective as to merit no serious consideration. It may be said that the first bombs dropped from an aircraft in the history of warfare were those loosed from the German Zeppelin which raided Antwerp in August, 1914. I speak with a certain personal knowledge of my subject, for the first bomb dropped on the night in question exploded less than a hundred yards from the window in which I was sitting, demolishing a house and killing three persons.

Many people seem to be under the impression that bomb-dropping is about as simple as dropping a brick out of an upper-story window onto the head of a man beneath. This is not so. As a matter of fact, it is extremely difficult to drop a bomb from an airplane so that it will hit a desired target, for, owing to the speed at which the plane travels, the bomb when released does not drop to the ground vertically, but falls in a parabolic curve, something like that described by a man who jumps from a street-car when it is in motion. For this reason the bomb must be released some moments before the airplane is directly over the target, the ability of an aviator to determine the exact moment to pull his release mechanism being acquired only through long experience. Bomb-sights have recently been perfected, however, which have largely eliminated this element of chance. These sights have numerical scales mathematically calculated, so that when adjusted for height, air-speed as shown by the air-speed indicator, and calculated speed of the wind with or against the airplane, two sighting points are moved into such a position that if the bomb is dropped when the desired target comes in line with them, it will reach its objective—provided, of course, the aviator has made his calculations and set his sights correctly. All this sounds rather complicated, I know, and it is complicated, but if the pilot uses the sight correctly his chances of hitting his target are enormously increased. All bombing planes are fitted with quick-release mechanisms, which hold the bombs firmly in a vertical or horizontal position, according to the type and size carried. On the smaller bombing planes, such as the De Havilland 4, the release mechanisms are placed underneath the fuselage or the lower wings, but on the large types, such as the Handley-Page, the bombs are carried inside the fuselage. By a quick jerk of a lever the pilot releases his bomb precisely as a hangman, by jerking a lever, drops the trap on which the condemned man stands. And the consequences are usually much the same in both cases.