Huge fifteen-inch guns snaked along, foot by foot, by powerful steam tractors. Then a long line of "four point five" batteries, each gun drawn by six horses, then a couple of "nine point two" howitzers pulled by immense caterpillar engines. When one of these caterpillars would pass me with its mighty monster in tow, a flush of pride would mount to my face, because I could plainly read on the name plate, "Made in U.S.A.," and I would remember that if I wore a name plate it would also read, "Made in U.S.A." Then I would stop to think how thin and straggly that mighty stream would be if all the "Made in U. S. A." parts of it were withdrawn. Then would come hundreds of limbers and "G. S." wagons drawn by sleek, well-fed mules, ridden by sleek, well-fed men, ever smiling. Although grimy with sweat and covered with the fine, white dust of the marvellously well-made French roads. What a discouraging report the German air men must have taken back to their Division Commanders, and this stream is slowly but surely getting bigger and bigger every day, and the pace is always the same. No slower, no faster, but ever onward, ever forward. Three weeks before the Big Push of July 1st--as the Battle of the Somme has been called--started, exact duplicates of the German trenches were dug about thirty kilos behind our lines. The layout of the trenches were taken from aeroplane photographs submitted by the Royal Flying Corps. The trenches were correct to the foot; they showed dugouts, saps, barbed wire defences, and danger spots. Battalions that were to go over in the first waves were sent back for three days to study these trenches, engage in practice attacks, and have night maneuvers. Each man was required to make a map of the trenches and familiarize himself with the names and location of the parts his battalion was to attack. In the American army non-commissioned officers are put through a course of map making or road sketching, and during my six years' service in the United States Cavalry, I had plenty of practice in this work, therefore mapping these trenches was a comparatively easy task for me. Each man had to submit his map to the Company Commander to be passed upon, and I was lucky enough to have mine selected as being sufficiently authentic to use in the attack. No photographs or maps are allowed to leave France, but in this case it appealed to me as a valuable souvenir of the Great War and I managed to smuggle it through. At this time it carries no military importance as the British lines, I am happy to say, have since been advanced beyond this point, so it has been reproduced in this book without breaking any regulation or cautions of the British Army. The whole attack was rehearsed and rehearsed until we heartily cursed the one who had conceived the idea. The trenches were named according to a system which made it very simple for Tommy to find, even in the dark, any point in the German lines.