“Have you anything for me to do, aunt?”
“Not at present, Robert.”
“Then I’ll study a little.”
There was an unpainted wooden shelf which Robert had made himself and on it were half a dozen books—his sole library.
From this shelf he took down a tattered arithmetic and a slate and pencil, and, going out of doors, flung himself down on the cliff and opened the arithmetic well toward the end.
“I’ll try this sum in cube root,” he said to himself. “I got it wrong the last time I tried.”
He worked for fifteen minutes and a smile of triumph lit up his face.
“It comes right,” he said. “I think I understand cube root pretty well now. It was a good idea working by myself. When I left school I had only got through fractions. That’s seventy-five pages back and I understand all that I have tried since. I won’t be satisfied till I have gone to the end of the very last page.”
Here his aunt came to the door of the cabin and called “Robert.”
“All right, aunt; I’m coming.”