She swished the wastepaper basket, again almost full of scrap paper, so that the rays of the sun, passing through window pane and water-filled bowl, struck upon the loose papers. In a few minutes a light smoke began to rise from the basket. A bit of the paper turned brown slowly, and then curled up and broke into flame.
“Great Heavens!” gasped the principal. “John, put that out! The girl is a regular little firebug! Is that what you have learned from your dipping into physics and chemistry?”
He ran and pulled down the shade to shut out the sun. Then he turned with both his hands held out to the trembling girl.
“I see! I see!” he cried. “I should have seen it before. ‘Mother wit,’ indeed! Colonel Swayne is right. You are an extraordinarily smart girl. That is how the fire started before—and the fish were dead when you emptied the bowl of water upon the burning basket.
“Your young friend is freed of suspicion, Miss Belding. I congratulate her on having such a friend. I congratulate you—— Why, why! my dear child! You are crying?”
“Because I am such a dunce!” gasped Laura, through her tears, and with both hands over her face.
“Such a dunce?” demanded the amazed principal.
“Ye—yes, sir! I should have known what started the fire all the time. I should have seen it at once!”
“Why, pray?”
“Because it was a burning glass that started another fire in Bobby’s father’s store that very day—and I put it out by shutting out the sun. I should have seen this right then and there, and saved poor Bobby all this trouble. Don’t call me smart! I—I’m a regular dunce.”