“How did he do that?” Charlie interrogated “Can you tell us, Joe?”
“Yes, I can, but——”
“Say, I’d rather have him tell us how he did this trick with the figures,” interrupted Harry. “Go on, Joe.”
“Well, it’s really very simple when you know,” said Joe. “You see the sum I made appear on the stone wasn’t the sum of the numbers you three fellows wrote down.”
“It wasn’t?” cried Tom, surprised.
“No,” went on Joe Strong, with a twinkle in his bright eyes. “I let Harry, Charlie and Henry each set down four figures on a piece of paper. Then I handed a piece of paper to Tom to add up the sum, only it didn’t happen to be the same piece that you three fellows used,” and Joe laughed.
“I just substituted one of my own,” resumed the boy wizard. “I had it in my pocket all ready, for I thought maybe I’d get a chance to play this trick to-day. I wadded up in a little ball the paper with the figures you boys set down, and slipped Tom one of my own. Of course I knew what my numbers were going to add up to—I had put down the figures myself, so I ought to know. They were like this:”
4,004
2,821
3,642