Thus it was impossible to guess where they were, or even to tell if they were alone or not.

"This is an outrage," said the doctor. "I protest against it. Is the author of a dozen immortal works to be treated like a naughty schoolboy?"

"We're prisoners," remarked Mont, "and it's no use hallooing. They're not going to eat us. This isn't an oven, and I think we are better here than up above."

"At least we had our liberty," continued the doctor, who was never satisfied or happy unless he was at work or grumbling.

"I've got a knife," said Stump boldly, "and I'll stick the first that comes near me. It's a regular pig-sticker, my knife, and I'll bet they feel it."

"Don't you do anything of the sort!" cried Mont. "You might get us all killed."

"It's very hard if a poor boy can't do something."

"You'll get it hot if anyone is listening to you. If you don't care for yourself, think of us."

Stump grumbled inaudibly, and Mont began to take the dimensions of the prison in which they were.

This he did by walking about, and he made it twenty feet long by ten wide. The walls were of iron, made of plates riveted together.