"I didn't want to alarm your uncle," said Armstrong, "but just now, looking through a chink in the boards, I saw four men coming towards the tower. What are we to do?"
Pratt went to the boarded window and looked out.
"Gradoff and the chauffeur," he said. "The other two I haven't seen before. We might have tackled two; let 'em in and bagged them. But four!--probably armed, like Jensen. It's no go."
"We can only lie low, then, and play for time. The door's a stout piece of timber, and it's not so easy to blow off a bolt as to blow in a lock."
"Don't speak," whispered Pratt, "they're just here."
The handle of the door was turned. Then came a sharp knock. A pause of a few seconds; then a more peremptory knock and Gradoff's voice.
"Jensen!"
The Swede prostrate against the wall wriggled and emitted a low gurgling noise through his gag. The boys glanced at him; he was unable to release his limbs; the sound could not have been heard through the thick door.
A third time Gradoff knocked. He rattled the door-handle, repeated his call, with the addition of sundry violent expletives. The boys remained tensely silent.
The voices without subsided. Conversation was still carried on, but in lower tones.