A man would climb as far as a tree would allow, and when the tree bent from their weight, it would catapult the man into the air. I'm not sure how this must have looked, but it doesn't sound like a strong choice of behavior. In fact, it seems more than slightly dangerous. As if to emphasize my point, Martin writes that he "would have one capital swing". Climbing farther than before. He relates that the tree bent "to about a horizontal position" before "it snapped off as short as a pipestem", dropping him an estimated 40 feet to the ground. "I brought it with all the force of my weight and its own directly upon the top of my unthinking skull, which knocked me as stiff as a ringbolt, he says.
Kids, please don't try this at home...or anywhere else for that matter. It sounds like Martin's headache lasted for several days and he got in trouble to his behavior choice.