“Let’s try the door,” he said.

It was now dark in the room, but both young men had matches, Tom’s being in a waterproof case which had kept dry during his sudden bath, and with these they made as good an examination of the door and its frame as was possible.

The lock defied picking with the poor tools at their disposal, and when this had been proved Tom said:

“We can cut a hole through the door near the lock, big enough for a hand to get through, and maybe we can turn the lock that way.”

“It’s worth trying,” Ned declared. “We’ll work at it in shifts.”

Their captors seemed to have made up their minds to leave the prisoners alone, though voices and movements in the rooms below indicated that the three men were still on guard. Perhaps orders had come from the mysterious “Chief” not to attempt violence.

There was more than enough food in the supply which had been brought to provide a late supper and even breakfast for the captives, and there was a large jug of water.

Throughout the hours of the night, Tom Swift and Ned Newton toiled desperately to cut a hole through the door. With only pocket knives to work with, it was tremendously difficult labor.

It was long past midnight when Tom, whose turn it was at the task, uttered an exclamation of dismay.

“What’s the matter?” asked Ned, who had thrown himself on the bed to rest. “Break your knife or cut yourself?”