All our hundreds of thousands of men, all the artillery, all the transport must move forward at night. To show lights was to sprinkle tell-tale stars in the carpet of darkness as another indication that a sector which had known routine quiet for month on month was awakening with new life that could mean only one thing to a military observer. With the first suspicion of an offensive the enemy's troops in the trenches would be put on guard, reserves might be brought up, machine-guns installed, more aviators summoned, trench raids undertaken, and all the means of information quickened in search for enlightening details. It was possible that the German might have learned our plan at its inception from secret agents within our own lines. If he had, it would not have been the first time that this had happened. In turn, his preparations for defense might be kept secret in order to make his reception hotter and more crafty. He might let the headlong initiative of our troops carry us into a salient at certain points before he exerted his pressure disastrously for us on our flanks. Thus he had met the French offensive of the spring of 1917; thus he had concentrated his murder from Gommecourt to La Boisselle in the Somme Battle. Not only had our army to "take over" from the French in all the details of a sector, from transport and headquarters to front line, but the Fourth French Army, on our left, which was to attack at the same hour, must be reinforced with troops and guns. The decision that the Saint-Mihiel offensive was not to follow through to Etain and Mars-la-Tour meant that French as well as American units and material must move from that sector to the Argonne. Immediately it had covered the charge of our troops the heavy artillery, both French and American, was to be started on its way, and, after it, other artillery and auxiliary troops and transport of all kinds as they could be spared. "It sounds a bromide to say that you cannot begin attacking until your army is at the front," said a young reserve officer, "but I never knew what it meant before to get an army to the front." He had studied his march tables at the Staff School at Langres; now he was applying them. Young reserve officers had a taste of the difficulties of troop movements. They had to locate units, see that they received their orders, and set them on their way according to schedule, with strict injunctions from "on high" to see that everybody was up on time. They had lessons in the speed of units and the capacity of roads which, at the sight of a column of soldiers on the march, will always rise in their recollections of anxious days.