"My father said yesterday that you had a big brain and a strong will," he answered from his bed. "He said that you had a wonderful memory which only needed exercising. He said it after he looked over the list you made of the things you had seen in the Tower."

The Rat shuffled on his sofa and clasped his knees tighter.

"Did he? Did he?" he said.

He rested his chin upon his knees for a few minutes and stared straight before him. Then he turned to the bed.

"Marco," he said, in a rather hoarse voice, a queer voice; "are you jealous?"

"Jealous," said Marco; "why?"

"I mean, have you ever been jealous? Do you know what it is like?"

"I don't think I do," answered Marco, staring a little.

"Are you ever jealous of Lazarus because he's always with your father—because he's with him oftener than you are—and knows about his work—and can do things for him you can't? I mean, are you jealous of—your father?"

Marco loosed his arms from his knees and lay down flat on his pillow.