With that there was a general exodus. The keepers, intent upon winning the reward issued for the escaped prisoners' arrest, seized their rifles and started in pursuit. Not having the faintest notion of the direction the fugitives had taken, they naturally concluded that they had made for the Unterland in the hope of being able to seize a boat. All this while Hamerton and Detroit were making towards the circular fence surrounding the Zeppelin station.
"Easy!" whispered the Sub, when they were nearly abreast of Spitz Horn. "We'll be tumbling upon the sentries if we are not careful. They have been warned for a dead cert."
Before Detroit could reply a tall, dark figure loomed up directly in front of them. A levelled bayonet glinted dully in the dim light and a guttural voice bade them stand on the pain of being instantly shot down if they resisted.
Oswald Detroit had not been a full back of his college team to no purpose. With a sudden panther-like spring he threw himself upon the ground right under the levelled bayonet.
The sentry made a bold attempt to shorten his weapon and lunge at his antagonist. He was the fraction of a second too late. The American's steel-like fingers gripped him round the ankles. His bunched head and shoulders caught the German a tremendous battering-ram-like blow just above the knees.
Swept off his feet by the impetus, the sentry fell heavily on the ground. As he fell his finger involuntarily pressed the trigger of his rifle. There was a deafening report. The bullet whizzed close to Hamerton's ear, while he clearly felt the blast of the detonation.
The sentry, stunned by the fall, lay like a log.
There was not a moment to be lost. The man's comrades, already on the qui vive, saw the flash and heard the report. The nearmost of the cordon ran to support the fellow who had raised the alarm.
Throwing themselves on the ground the Sub and his companion crawled in a direction that was practically at right angles to the imaginary line between the two nearest sentries. As they did so they heard the swish of a man's boots shearing through the long, damp grass.
Once more luck was in their favour, for the oncoming sentry passed them within a distance of ten yards. So intent was he upon finding his comrade that the two men lying prone upon the ground were unobserved.