“Why, I suppose just as if you were going to throw the ball straight. ‘The back of the hand being turned away from you.’”
“Yes.”
“‘In delivering the ball, bring the back of the hand underneath as the arm is dropped, letting the ball roll off the surface of the confining fingers, which imparts to it the rotary motion necessary to make it curve to the pitcher’s left.’ That sounds crazy to me!”
“Me too. But here goes!”
The ball shot away and the boys watched it eagerly. There was undoubtedly a slight tendency toward an out-curve, but certainly not enough to fool the stupidest batsman. But Tom was pleased.
“That’s the idea, all right,” he declared jubilantly. “Now we’ll try it again.” Sidney obligingly recovered the ball, which, luckily, had struck the fence instead of going through any of the numerous holes in it. He tossed it to Tom, and Tom again carefully and thoughtfully arranged his fingers about it, poised it over his shoulder, and swept it forward. But this time something was very wrong, for the ball swooped down to earth some fifteen feet distant, struck an empty tin can, and bounded off into the street.
“I’ll chase it!” said Tom.
“No, you stay there,” laughed Sidney, “and study about it. I’ll get it.”
“What I’d like to know,” said Tom, when Sidney was back once more, “is what makes it curve.”
“Why, it curves because you hold it so it will!”