The sound of cannonading grew fiercer and fiercer, as they advanced, and the undertone of rifle fire more perceptible. It was evident that the Germans were rapidly getting more and more guns into action, and that the infantry attack was also being hotly pressed. Below them in the valley, they caught glimpses from time to time, as the trees opened out a little, of the gray-clad host marching steadily forward, as though to overwhelm the forts by sheer weight of numbers; and then, as they came out above a rocky bluff, they saw a new sight—an earnest that the Belgians were fighting to some purpose.
In a level field beside the road a long tent had been pitched, and above it floated the flag of the Red Cross. Toward it, along the road, came slowly a seemingly endless line of motor ambulances. Each of them in turn stopped opposite the tent, and white-clad assistants lifted out the stretchers, each with its huddled occupant, and carried them quickly, yet very carefully, inside the tent. In a moment the bearers were back again, pushed the empty stretchers into place, and the ambulance turned and sped swiftly back toward the battlefield. Here, too, it was evident that there was admirable and smoothly-working system—a system which alleviated, so far as it was possible to do so, the horror and the suffering of battle.
Stewart could close his eyes and see what was going on inside that tent. He could set the stripping away of the clothing, the hasty examination, the sterilization of the wound, and then, if an operation was necessary, the quick preparation, the application of the ether-cone and the swift, unerring flash of the surgeon's knife.
"That's where I should be," he said, half to himself, "I might be of some use there!" And then he turned his eyes eastward along the road. "Great heavens! Look at that gun."
Along the road below them came a monstrous cannon, mounted on a low, broad-wheeled truck, and drawn by a mighty tractor. It was of a girth so huge, of a weight evidently so tremendous, that it seemed impossible it could be handled at all, and yet it rolled along as smoothly as though it were the merest toy. Above it stretched the heavy crane which would swing it into the air and place it gently on the trunnions of its carriage. Drawn by another tractor, the carriage itself came close behind—more huge, more impressive if possible, than the gun itself. Its tremendous wheels were encircled with heavy blocks of steel, linked together and undulating along the road for all the world like a monster caterpillar; its massive trail seemed forged to withstand the shock of an earthquake.
"So that is the surprise!" murmured the girl beneath her breath.
And she was right. This was the surprise which had been kept so carefully concealed—the Krupp contribution to the war—the largest field howitzer ever built, hurling a missile so powerful that neither steel nor stone nor armored concrete could stand against it.
In awed silence, the two fugitives watched this mighty engine of destruction pass along the road to its appointed task. Behind it came a motor truck carrying its crew, and then a long train of ammunition carts filled with what looked like wicker baskets—but within each of those baskets lay a shell weighing a thousand pounds! And as it passed, the troops, opening to right and left, cheered it wildly, for to them it meant more than victory—it meant that they would, perhaps, be spared the desperate charge with its almost certain death.
Scarcely had the first gone by, when a second gun came rolling along the road, followed by its crew and its ammunition-train; and then a third appeared, seemingly more formidable than either of the others.
"These Germans are certainly a wonderful people," said Stewart, following the three monsters with his eyes as they dwindled away westward along the road. "They may be vain and arrogant and self-confident; apparently they haven't much regard for the rights of others. But they are thorough. We must give them credit for that! They are prepared for everything."