"Railway ahead!" whispered Kenneth.
Outlined against the starry sky was a low embankment, fringed with the characteristic telegraph poles of the Belgian state railways. Directly in their path was a culvert, on the top of which were the silhouetted figures of three greatcoated soldiers. On the other side of the embankment a fire was burning brightly, its glare alone betraying its position.
The fugitives promptly retraced their steps for nearly two hundred yards, then striking off at right angles kept parallel to, and at a fairly safe distance from, the railway line.
"We'll have to cross that line," whispered Kenneth. "It runs between Liége and Aix, I believe."
"Let's hope the whole extent of it isn't guarded."
"Only the bridge and culverts; but you can take it for granted that they patrol between the various posts of sentries. Carry on, old man; another half a mile and we'll try again."
A short distance farther the fugitives encountered the main road from Liége to the German town of Aix-la-Chapelle. It was quite deserted, but beyond it they had to turn slightly to the right to avoid the railway, which ran in a north-easterly direction.
"Why not have a shot at it?" asked Kenneth.
"Not yet. It will run in a northerly direction again. I noticed that in the map. We must cross, if possible, somewhere to the south of Aubel. It is still early in the evening. The nearer midnight we make the attempt the better."
It was now bitterly cold. A hard frost made the ground like iron. Since it was too hazardous to proceed at a rapid pace, the lads felt the piercing air accordingly. With their shoulders hunched and their ungloved hands thrust deeply into their pockets, they kept on, shivering in spite of the fact that in the excitement of regaining their liberty—temporarily, at any rate—their nerves were a-tingle and the blood surged rapidly through their veins.