"We watched him row past it," said Warrender. "He's probably off to his hut. Let's hope that the other fellows are at the house and not at the tower."
"It's 'over the top' now," remarked Armstrong, as the boat sidled away from the landing-stage.
CHAPTER XIX
THE PRISONER
Pratt was the only one of the three who had the curiosity to look at his watch when they descended into the cellar of the ruined cottage. It was twelve minutes past ten.
They had tied up the motor-boat at its moorings below the camp, and after a careful look-out in all directions, had crossed to No Man's Island by Mr. Crawshay's pram. For weapons Pratt and Armstrong each carried a short thick cudgel; Warrender at the last moment caught up his spanner, remarking that he might need a knuckle-duster.
The flat stone was revolved. They sprang lightly into the cavity below.
"Shall we leave it open in case we have to come back in a hurry?" asked Warrender in a whisper.
"Better close it," said Armstrong. "If Rush or the other fellow turns up and finds it open we may be fairly trapped."
Having made all secure they stood for a few moments listening. There was no sound.