The spy's wild eyes were fixed on the English soldier's grim face. He knew when a man meant what he said, and he dropped the knife.
'Step two yards back,' went on the sergeant. The spy did so.
'One o' you boys pick up that knife,' murmured the sergeant; and Dick ran and fetched it.
'Now, I'm in the dark yet,' went on the sergeant quietly; 'all this looks very suspicious, but how do you boys come to reckon you've nabbed a spy?'
Dick began with the boot and the papers hidden in it.
'That's enough, my lad,' said the sergeant. 'We'll lose no time. There's plenty o' reason, I can see, to take him in on suspicion, and after hearing that I'd shoot him at once if he tried to escape. Now you,' he went on to the spy, 'turn right round and march ahead as I tell you. And remember I'm a yard behind you with a cocked revolver. March!'
The spy turned, and went as he was bidden.
'Come on, boys; you must come with me,' said the sergeant and the little party went across the heath, the prisoner turning as the sergeant bade him, and taking as direct a line as possible to the Horseshoe Fort.
An hour later Dick and Chippy found themselves in the presence of the officer in charge of the works at the fort. The prisoner had been handed over into safe keeping, and the sergeant and the two boys had been ordered to report to the colonel himself.
They were shown into a large bare room where a tall man was seated at a great table covered with papers. He stood up, as they went in and saluted, and posted himself in front of the fire.