BOOK III.
THE ENGINEER CORPS.
CHAPTER I.
THE ENGINEERS IN FRANCE.
In describing the activities of the Engineers, we are carried to the front itself, into the zone beaten by enemy fire, where machine-gun bullet, bursting shell, and deadly gases have brought sudden death and painful wounds to many members of the technical services. A large proportion of the Engineers are combatant troops, constituting in the American Expeditionary Forces about 8 per cent of the total combatant troops engaged. These troops, trained and equipped to march and fight as Infantry, demonstrated their fighting qualities during the war on numerous occasions, both when used as Infantry to increase the rifle strength of that arm and when fighting as Engineers to obtain possession of terrain as a preliminary to the exercise of their technical art in its organization.
From the day the first sector was taken over by American troops in November, 1917, until the Meuse River was passed and the enemy, in flight, sought an armistice to save his armies from destruction, the combatant Engineers—the "sappeurs" of French soldier lore and song—- fought and bled in a manner never to be forgotten. Railroad engineers, nominally considered noncombatant, at Cambrai dropped their tools to take arms and stand stubbornly shoulder to shoulder with their British brothers with whom they were learning to work under the special conditions of the front. From Cantigny to Chateau Thierry, Engineer troops fought as well as worked, and often not only advanced with the Infantry under or through the barrage, but actually led the first wave, to demolish or remove the obstacles placed in its path. Through the days when from March 21, 1918, until July 18, 1918, the German army made its rapid plunges toward Paris until checked and thrown back across the Marne at Chateau Thierry, the sapper troops fought and worked with the Infantry of their divisions, enduring the same dangers, privations, and hardships, and winning equal honors and commendation.
In the drive at St. Mihiel and through the Argonne, the combatant Engineers played a conspicuous part. Advancing with the tanks, they made possible the passage of many difficult points for these lumbering monsters, against which was directed a particularly destructive fire. Using elongated torpedoes of high explosive, known as Bangalore torpedoes, they prepared passages for the Infantry through the broad barbed-wire entanglements, echeloned in depth by numerous separate lines, each to be breached and passed before the objective could be gained. In this work the Engineers reduced the machine-gun nests that hindered their operation, cleaned up the strong points that delayed the advance of the tanks they were assisting, and threw extemporized footbridges across the streams which barred the further advance of the Infantry.
The combatant Engineers did their part in the winning of the reconquered ground as well as the lion's share of its organization for the defense and the maintenance of the communications behind it. In this last respect alone, the Engineers, as combatant troops, opened across No Man's Land the first communications practicable for the light field artillery, which pressed forward immediately behind the Infantry troops to their support and protection.
Filling in trenches, removing wire entanglements, building trestles across wide mine craters, searching for and rendering inoperative treacherous mines and traps of extreme ingenuity and destructiveness, the sapper found a wide field for the exercise of his functions. Shattered and obliterated by four years of shelling and mining, trenching, and countermining, the "roads" across No Man's Land existed only on the map; and as they retreated the Germans demolished and obstructed the highways behind the old front from which they had been driven, with the thoroughness and attention to detail for which they are noted. As our Infantry advanced, upon their heels, literally speaking, came our Engineers, to attack the problem of providing for the Artillery and supply trains a means of following. From the standpoint of the road builder in civil life, their methods were crude in the extreme, but for the military purpose and the pressing immediate needs, their road building achievement was adequate. The Engineers sometimes reopened abandoned quarries, and sometimes started them where none had existed before, to obtain a supply of road metal, which supply was sometimes supplemented and in some cases replaced by the use of debris from ruined villages and shattered farmhouses. From demolished structures many useful materials were extracted and adapted to the military purpose by the Engineers. Where bridge and trestle timbers were lacking, deserted buildings—in one case the tower of a ruined church—filled the need. Where shell hole or crater yawned a remnant of a stable wall might be pulled down by ropes and man power, and broken up to fill the void.
Through the dense woods the soft forest floor offered no support even to the light artillery, and miles of corduroy and brush path were built to permit the guns to advance to the reinforcement of the attack. In many places the tactical situation admitted of insufficient time to build even the crudest paths, and then the Engineers fell to and assisted artillery and supply wagons to get through and over the bad spots, replacing guns on the road where they had run into the ditch, righting and reloading combat wagons when they had turned over in shell holes or deep ruts.