They rode across the field and then through a belt of open forest, but the fog was so dense they were compelled to keep close together lest they lose one another. The rolling sound increased and now other notes came with it. A little farther and they saw dim lights in the fog.
"An army," whispered Carstairs, "and the torch-bearers are showing the way through the fog. Now what kind of an army is it?"
"German of course," said Wharton. "We know well enough that no French force is near here. It's a part of the flood that's bearing down on France and Belgium."
"There are more trees here to the right," said John. "Let's enter them and get a better view. Even if we were seen we could escape anybody in this fog."
"Good idea," said Carstairs. "I'm as anxious as you to know more. This fair land of France is bearing strange fruit now."
Keeping a wary eye for Uhlans who must be somewhere near they rode with all the courage of youth into a clump of trees that grew upon a hillock close to the road. There, in the shelter of the foliage, they looked down upon what was passing.
"Busy Bertha!" said Wharton.
John beheld a giant cannon, one of the mighty howitzers which he had treated as a fable, a soldier's idle dream, until he had heard it booming in the night. But here was another drawn by a powerful motor. Its monster mouth was turned up at an angle toward the sky, and in the fog lighted only by the torches the thing became alive to John, huge and misshapen, dragging itself over the ground, devouring human beings as it went, like the storied dragons of old.
He glanced at his comrades and saw that the monster had taken hold of them in the same way. They were regarding it with a kind of awe, and yet it was not alone. Its sinister shape merely predominated over everything else. It was preceded and followed by many other cannon, giants themselves, but overshadowed by the mammoth.
Motors drew most of the great guns, and there were thousands more carrying soldiers, arms and various kinds of equipment. Behind them came vast masses of gray infantry, marching with the steady German tread. The heavy fog, which the torches lighted but dimly, magnified and distorted everything, and the sight was uncanny and terrifying.