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.
I fully realize that what I have written in the preceding pages contains
no mention of the supply work performed by the corps in the United
States, which was so enormous that 27 per cent of all the tonnage
shipped to France up to the signing of the Armistice was from or for
the Engineers. Furthermore, I have touched only here and there upon the
activities of the corps oversea, where in addition to the enormous amount
of engineering work which had to be done with the armies, including
fighting, the construction of fortifications, and the building of roads,
railways, and bridges, it executed an incredible amount of general
construction, such as docks and warehouses, railroad yards and railroad
bridges, camps and hospitals, balloon sheds and airplane hangars, not
to mention the installation of water, heating, lighting, and sanitary
systems. And, bear in mind, the oversea activities of the Engineers
were not confined to France, but extended to England, Italy, Russia, and
Siberia.
* * * * *
“_Essayons!_” The more I have seen of the work of the Engineers, the more
appropriate seems their motto.
“_Essayons!_” There is apparently nothing that these men with the
castles on their collars will not essay. And everything they essay they
accomplish.
III
THE GAS-MAKERS
Were you to grow up with a boy who eventually became widely talked about,
watching him pass from knickerbockers to trousers and from youthful
shyness to burly aggressiveness, the chances are that you would follow
his career with an almost proprietary interest, and that when you came
upon his picture in _The World’s Work_ or _The Police Gazette_, according
to whether he had become famous or notorious, you would display it to
your friends, explaining proudly: “Why, I’ve known him ever since he was
a youngster. I always felt sure that he would attract attention some day.”
Such, in a manner of speaking, has been my acquaintance with poison-gas,
or toxic-gas, as the chemists call it. I was in the Ypres salient, on
the British front, when the first gas attack in the history of warfare
was launched against the Africans and Canadians on April 22, 1915, and
that night, in the hospitals, I saw the earliest victims of gas warfare,
gasping on their cots like fish thrown on the bank to die. On several
occasions during the months which followed I again encountered the malign
creature—on the Yser, in the Champagne, in Alsace, and on the Isonzo—and
on each succeeding occasion it was more threatening and was causing
greater concern. So that when, after the United States had been at war a
year or more, I visited the great arsenal at Edgewood, on the shores of
Chesapeake Bay, and was shown the vast plants devoted to the production
of chlorine, chlorpicrin, phosgene, mustard, and other deadly gases, and
caught the familiar nauseous odor, I felt as though I were renewing an
old and undesirable acquaintance.