Part 7

The best and most concise rules which I have seen for the erection of camouflage and for the enforcement of camouflage discipline are contained in secret instructions issued in July, 1918, by the commander of the German First Army. They read as follows:

CAMOUFLAGE

Translation of a German Document (from French IV Army Bulletin, August 8, 1918)

1st Army Command of the Aviation Service Ia-Ib

ARMY HEADQUARTERS, July 1, 1918.

I. ESSENTIAL POINTS IN THE CONSTRUCTION OF POSITIONS.

(_a_) _General._

1. Camouflage will be completed before undertaking the work.

2. Camouflage will be sufficiently extensive in order that all the work required may be carried out under its protection.

3. Faulty installation will be left in place as dummy work and be begun over again at another point with the necessary prudence.

(_b_) _Tracks._

1. Tracks must be as few as possible and have a natural appearance. It is best to avoid all tracks by building the position on roads already in existence.

2. Provide fixed access for everybody. If necessary, stake the paths out by means of wire.

3. Extend indispensable tracks beyond the position as far as the dummy work.

4. Use furrows as paths, do not go across fields.

5. Do not dump materials in the immediate neighborhood of the position.

(_c_) _Color of the Camouflage._

1. Harmonize the color of the camouflage with the terrain. Green camouflage in meadows, brown in ploughed fields, white in quarries.

2. The upper surface of the camouflage will be alternate light and dark tones; grass, reeds, hay, or branches fixed in iron wire, etc.

3. Renew the camouflage in proper time; the grass and branches fade quickly and appear light and not dark on the photographs.

4. The position must not extend partly over one field and partly over another, as two fields are seldom of the same color. The furrows will be reproduced in the camouflage.

5. Camouflage materials, such as the sod removed and small trees, will be taken at a distance of at least three to four hundred meters from the position; place a dummy work at a sufficient distance in order that it does not reveal the true position.

(_d_) _Forms of Camouflage._

1. Do not raise the height of the camouflage needlessly; the higher it is the more shadow it throws. Raise it by means of posts during the work; bring it down by day and lay it flat if possible; cover mainly the entries and exits.

2. Do not make a heap of the earth removed but scatter it immediately.

3. There must be no fresh cuts visible, as marked contrasts result from it between the light and dark surfaces, the latter appearing as deep shadows on the ground.

4. Avoid regular shapes and rectangular outlines.

5. Do not change natural shapes. Positions in fills and embankments must not change the form of the fill or embankment.

6. Use the roads, fills, embankments, slopes, sunken roads, edges of woods to greater extent. Deceive the enemy by false tracks ending in woods.

II. MAIN INSTRUCTIONS FOR COLUMNS.

(_a_) Resting columns, location, and nature of halting-places. The most important thing is that the halting-places be of irregular form.

1. It is best to distribute the columns irregularly under trees of gardens, avenues, roads, and courtyards, even if not very dense.

2. The camouflage of wagons or artillery pieces by means of branches does not secure them from reconnaissance by airplanes, when the column is in the open on light-colored ground, as, for example, on dry roads. Shadows enlarge in a surprising manner.

3. In villages, keep close to the houses, walls, enclosures of gardens and hedges, but, if possible, with irregular distribution. The best side is always the north side of houses, walls, etc., on account of the shadow.

4. In small courtyards the wagons are lined up one beside the other and the tarpaulins joined in order to make a roof. This appears as a smooth and very natural surface on the photograph, which does not attract the enemy’s attention.

5. Lessen the tracks, if possible. Do not widen the roads of approach uselessly. Follow the track. Mark out footpaths, staking them out, if necessary, by wire.

(_b_) Troops on foot, wagons, and artillery columns on the march.

1. Even at night make more use of tracks which are generally dark; the columns can then with difficulty be observed by airplanes; on the other hand, columns on roads which appear light can be seen even at night.

2. Infantry columns will be divided into small groups distributed in depth and advance along the shady side of roads.

3. When airplanes use light projectors at night keep in the shade of trees or buildings.

III. GENERAL RULE.

When surprised by airplanes, either by day or by night, use all natural shade provided by trees, embankments, houses, etc., and remain motionless.

By Order of the General Commanding the Army.

CHIEF OF STAFF. (Signed) FAUPEL, _Lieutenant-Colonel_.

So great, indeed, was the importance attached to camouflage by the German High Command that, during the last year of the war, there was attached to every German division a “security officer” whose duty it was to enforce the rigid observance of camouflage discipline. In many cases these security officers kept a watch on their respective division from observation-balloons. They were answerable only to Great Headquarters and were empowered, I understand, to recommend the removal of all officers up to and including generals of division for infraction of the rules for camouflage discipline as laid down by Ludendorff.

Camouflage, it should be kept in mind, is of two kinds—negative and positive. Negative camouflage consists in the concealment of troops, trenches, mine-shafts, battery positions, ammunition-dumps, hangars, or other objects, knowledge of whose location must be kept, if possible, from the enemy. Positive camouflage, on the contrary, consists in the imitation or suggestion of troops, trenches, batteries, etc., in certain locations, when, in reality, there is nothing of the sort there, in order to deceive and bewilder the enemy. It occasionally became necessary, for example, to convince the Germans that a large troop movement was in progress behind a certain sector of the front, whereas the real movement was taking place scores of miles away. If it was desired to suggest a movement by rail, smoke-pots with clouds of dense black smoke bellying from them were placed on flat cars and moved about from point to point on the military railways. German aviators, observing these columns of smoke at numerous points along the railways, naturally assumed that they came from locomotives hauling troop-laden trains and promptly reported that large bodies of troops were apparently being moved by rail behind the American lines. Thereupon the German commander would rush up his reserves to resist the attack which he believed to be impending. Or, if it was desired to imitate a troop movement by road, the camouflage officer would requisition large numbers of Fords, which would be driven madly along the roads, dragging bundles of brush behind them. The great clouds of dust which thus suddenly appeared on the highways naturally suggested to the German observers that the _verdamte_ Yankees were rushing large bodies of troops to the front by bus or motor-truck. Fooling Fritz was an amusing game while it lasted.

This latter ruse, I might mention parenthetically, was not original with the Americans, for President Diaz, of Mexico, once related to me how, when he and his little band of patriots were being hotly pursued by the French forces sent to Mexico to keep Maximilian on his unstable throne, he ordered his vaqueros to cut bundles of mesquite and drag them behind them by their lariats. It was in the dry season, and the dense clouds of yellow dust thus stirred up convinced the French commander that the Mexican force was far stronger than it really was. He thereupon precipitately abandoned the pursuit and a few weeks later General Diaz, having gained the breathing-spell necessary to augment his forces, fought and won the decisive battle of Puebla.

It has frequently been said that the camera does not lie, but such assertions were made before the Camouflage Corps commenced its operations. Thereafter the negatives brought in by the German airmen began to prove so unreliable that the officers whose business it was to interpret them never knew whether they were telling the truth or not. For example, it frequently became necessary after heavy bombardments in which long stretches of entanglements had been destroyed, to convince the enemy that the wire had been repaired. This illusion was accomplished by the simple stratagem of driving stakes into the ground and festooning them with fish-nets, for, in a photograph taken from the sky, fish-nets thus arranged are indistinguishable from wire. If such ruses are to deceive the enemy, however, as much attention must be paid to detail in their execution as David Belasco pays to detail in the production of a play. On a certain British sector a not overintelligent subaltern was ordered by his battalion commander to take a working party and put out some 500 yards of this imitation wire, as there was reason to believe that the Huns, thinking the sector unprotected by entanglements, were preparing to make an attack. Now it is some job, even for a large and well-trained working party, to put out 500 yards of wire in much under a day. Heedless of such minor details, however, the lieutenant gayly slammed in his stakes and spread his fish-nets as fast as his men could work, “wiring” the 500 yards of front in little more than an hour. From high in the blue German airmen photographed the proceeding. When one set of photographs showed a sector destitute of wire and another set of pictures, taken an hour later, showed the same area with a complete system of wire entanglements, the suspicions of Von Hindenburg’s intelligence officers were naturally aroused, and the next morning at dawn the Germans launched their attack. In camouflage work one can’t afford to be slipshod.

The most elaborate camouflage works can be rendered utterly useless, however, by the carelessness of a single soldier, for there is little that escapes the eye of the airman’s camera, particularly when it was fitted, as during the latter days of the war, with a stereoscopic attachment. I remember that in one of the Champagne sectors the Germans had installed a battery of heavy guns which were so ingeniously concealed that the French were unable to locate them. It was believed that they were hidden somewhere in a fringe of woods along a stream, but though there was a considerable area of cultivated land beyond the woods, the aerophotographs of it showed nothing which would suggest a path such as would be made by artillerymen going to and from their guns. One day, however, a new batch of plates, upon being developed, showed a dim gray line, faint as the shadow of a hair, leading across this cultivated area to a small wood on the bank of the stream, where a battery might easily be concealed. Upon studying an enlargement of the picture the intelligence officers became convinced that the shadowy line on the negative really represented the trail left by a soldier crossing the field. Proceeding on the surmise that the soldier was an artilleryman going up to his gun-position, the French gunners registered on that particular patch of woods the following morning, whereupon the fire from the concealed battery abruptly ceased. German prisoners captured a few days later explained how the secret of the battery’s position had been kept so long. The German security officer had issued orders that the artillerymen must under no considerations walk across the fields in order to reach their guns, but that they must instead follow a much-used highroad until they reached a bridge over the stream, drop from the bridge into the water, and wade up the stream until opposite their position. But one night an artilleryman, in a hurry to reach his battery and confident that the tracks left by a single man could do no harm, took a chance and a short cut across the forbidden field. I have told you what happened to his battery as a result of his carelessness. Knowing something of German discipline, I can imagine what happened to him.

But it was not often that the Germans were caught napping, and so ingenious were some of their ruses and stratagems, that it required an intelligence officer with the imagination of a Sherlock Holmes to keep up with them. During the operations on the Flanders front a British aviator brought in some photographs of a certain area behind the German lines. The intelligence officer whose duty it was to scrutinize them detected a suspicious something which he was convinced was a cleverly camouflaged German battery, but though it was in the midst of open country there was no suggestion of a path leading to it. After studying the photographs for several hours he suddenly exclaimed:

“I have it! They get up to the guns on the covers of biscuit-boxes.”

“What do you mean?” his chief asked curiously.

“It’s as plain as the nose on your face,” explained the youngster. “The Boche knows jolly well that if he walked across that open ground his tracks would show up in our air photos. So when he wants to get up to his battery he gets a couple of wooden biscuit-box covers and ties strings to them. He stands on one cover and throws the other ahead of him, then stands on that and drags up the first cover by means of the string and repeats the operation. Deuced clever of the beggars, I call it.”

And, as subsequent events proved, the intelligence officer was right in his deduction. That was precisely what the Germans had done.

By far the most important work of the Camouflage Corps was the construction of “flat-tops” and “false contours.” A flat-top, I should perhaps explain, is a screen for concealing a gun from enemy observation. It consists of a fish-net, usually 37 feet square, into the mesh of which are woven and knotted narrow strips of burlap of colors to blend with the vegetation of the region where the flat-top is to be used. The interwoven burlap becomes gradually thinner as the edges of the net are approached, so that no sharply defined shadow may be cast. Every piece of artillery, large and small, in the A. E. F. had its own flat-top, which accompanied the gun everywhere, being stretched above it, like a canopy, when the piece was in action, at other times being rolled up and carried on the limber. A somewhat similar device was also provided for the concealment of machine-guns. It resembled one of those huge umbrellas used in summer on delivery-wagons, and, like an umbrella, it could be quickly raised or lowered. It was the intention of the Camouflage Corps, had the war continued, to provide one for every machine-gun.

A false contour can best be described as the prolongation, by means of burlap spread over a sort of wire trellis, of a ridge, promontory, or hill. It being desired to place a battery at the foot of a hill and at the same time conceal it from enemy observation—which included photographs taken from enemy airplanes—the Camouflage Corps would first of all erect a light wooden framework, something like that of a grape or rose arbor, but conforming to the general contour of the hill. Over this framework was stretched wire netting, which supported, in turn, a finer mesh of chicken-wire, into which were woven strips of burlap dyed so as to exactly match the color of the hill itself. The space beneath this burlap screen provided perfect concealment for anything up to a battery or a battalion, while so closely was nature imitated in the shaping and coloring of the false contour that photographs taken by enemy flyers would show only an innocent hillside, with not enough vegetation to provide cover for a sniper. The burlap used in the construction of these false contours was frequently “slashed,” after the fashion of foliage-drops in theatres, and was dyed in a great variety of shades, all of which were standardized and could be ordered by number. There were burlaps slashed and dyed to imitate ploughed fields, grain-fields, roads, lawns, quarries, water, rocks, and spring, summer, autumn, and winter foliage; in short, every phase of nature as found in the zone of operations.

[Illustration: SUITS KNOWN AS CAGOULES.

These suits are made of burlap and painted to match the vegetation and were frequently used by American snipers and raiding-parties.]

[Illustration: THE WORK OF THE CAMOUFLAGE CORPS.

As the enemy had this road under direct observation, traffic along it was concealed by means of burlap screens.

_Photograph by Signal Corps, U. S. A._

An overhead road screen made of burlap strips and chicken wire.

_Photograph by Signal Corps, U. S. A._]

The first time I visited the big warehouse of the Camouflage School at Fort St. Menge, I thought for a moment that I was back in the old Eden Musée which used to stand in West 23d Street, for stacked against the walls were scores of lifelike silhouettes of soldiers charging with fixed bayonets, while the shelves were lined with soldiers’ heads beautifully executed in papier-maché. The silhouettes, which were of painted canvas mounted on light wooden frames, were used in the so-called “Chinese attacks”—an idea which we borrowed from the British. When it was necessary to ascertain how quickly the enemy could switch on his artillery-fire in a certain sector, or the location of his batteries or machine-guns, a hundred or more of these silhouettes would be carried out into No Man’s Land under cover of darkness and laid down in front of our wire in such a manner that they could be pulled upright by means of cords running back to our trenches. Just at daybreak, at that hour when objects are still indistinct and when the nerves of the men in the trenches are at the greatest tension, a signal would be given, the cords pulled, and a long line of what appeared to the startled Germans to be charging Yankees would suddenly appear in the mist overhanging No Man’s Land. Instantly the German trenches would crackle and blaze with musketry, the concealed batteries and machine-gun nests would betray their positions by going into action, and by the time the Huns discovered the hoax that had been played upon them, our observers had obtained the information which they required. Sometimes, in order to further chagrin the Boche, the silhouettes would be left standing.

The papier-maché heads to which I have already referred were used for the purpose of locating German snipers. When a sniper became particularly annoying and defied all attempts to locate him, the camouflage officer attached to the division would be summoned. Under his direction a papier-maché effigy of a soldier’s head, steel helmet and all, made so as to move up and down in wooden guides, would be set up in that part of the trench which the sniper had been annoying. At intervals the head would be slowly raised and lowered, so that from the outside of the trench it looked precisely like a soldier peering cautiously over the parapet. Sooner or later the hidden marksman would send a bullet through the careless Yankee’s brain. The neat hole drilled through the papier-maché showed the exact direction from which the bullet came, and by inserting in the hole a tiny telescope, no larger than a pencil, and looking through it by means of a periscope, the loophole from which the sniper was firing could be located. In one case a sniper was found to be firing through a hole bored in the heel of an old boot, apparently thrown carelessly onto the glacis.

Though I have described at some length the use of silhouettes and papier-maché heads because they are picturesque and interesting phases of modern war, it should be borne in mind that they were designed to meet exceptional conditions, that they were used infrequently, and that they were in no sense typical of the enormously important work of the Camouflage Service.

* * * * *

In the foregoing pages I have sketched the multitudinous activities of the Engineers only in the barest outline. To attempt to compress the story of their achievements into the limits of a single chapter would be absurd, so I have dwelt only on the most picturesque and unusual phases of their work—the high spots, as it were. There is much that I have left unsaid, not because it is not worth saying, but because I have no space in which to set it down. The stories which I have had, perforce, to leave untold would in themselves fill a volume. Among their other accomplishments the Engineers designed a portable steel bridge, made up in sections so that it could be transported on trucks, and so designed that it could be bolted together, which could sustain a load of thirty tons over a span of ninety feet. These bridges were used all along the fighting front, as our forces advanced, to replace the bridges destroyed by the retreating Germans. They had under construction, when the war ended, a raft designed for the transportation of the heaviest pieces of mobile artillery in existence—by means of which, had necessity required it, we could have ferried our giant howitzers across the Rhine. The portable floating foot-bridges—passarelles—which our troops used in crossing the Meuse and the adjacent canals under fire were invented by an officer of Engineers. The Engineers threw one of them across the Canal de l’Est, near Dun-sur-Meuse, under a shell and machine-gun fire so heavy that it was twenty-six hours before the infantry could cross it. The Engineers have invented a very ingenious and remarkable device whereby search-lights can be operated from a distance, thus making it possible for an officer to control a battery of scattered search-lights just as the man in a signal-tower controls, by means of levers, the switches in a railway yard. The corps has perfected a blasting machine for demolition work which destroyed ruins faster than the Huns could make them. Military operations are absolutely dependent upon maps and plenty of them. The Engineers met the demand by erecting and operating in France a larger map-producing plant than was possessed by France herself or any of the Allies. In order to provide a more rapid means of obtaining topographical information, Major James W. Bagley, of the Engineers, invented an aerial cartograph or mapping camera, which takes three pictures at a time from an airplane, mapping a strip of territory three and a half miles wide at 5,000 feet elevation, the series of pictures thus taken forming a mosaic map of the country over which the airplane has flown which is as accurate and far more detailed than a map drawn from surveys. This invention opens up an entirely new field for the use of airplanes and a possible revolution in former methods of mapping. The Engineers likewise produced portable machine, blacksmith, and lithographic shops, the capacity of the portable lithographic truck-sets furnished the 29th Engineers—the Surveying and Printing Regiment—being greater than that of the permanent map-reproduction plant of the Geological Survey in Washington. Mobile sterilizers, water-tanks, job-presses, photographic laboratories, derricks, pile-drivers, road-sprinklers, and oilers were all asked for by the A. E. F., whereupon the Engineers designed them and shipped them to France.