Pocket full of worms
The old man carried the worms in his pocket, while he puttered around, and sometimes he'd think of experiments for them. He'd stick his hand in his pocket, in the dirt there, and feel them, wiggling and waiting for experiments.
People worried about the old man, Mr. Darwin, the distinguished Victorian with the stately beard and reputation. He was acting strange. He was acting like a boy. He was always like that, a little, with the barnacles and the tests with the fermenting barrels of salt water, but those had been important. There had been a theory, a bid idea, something important, and this was just a ball of naked, wiggly worms. He kept them in his pocket.
He'd walk around with his worms and come up with silly, stupid tests. "Can worms hear?" he would wonder, and then he'd test it. He put them on top of a piano while his daughter was playing. She played, pounding away at her assigned scales, and he watched the worms closely, trying to see if they responded in any way. "Can you hear?" he would say, and his daughter would give him a look. He paid a kid from down the street to blow a whistle at the worms, and the little boy whistled and whistled as shrill as he could, wanting to earn his money, but the worms didn't seem to do anything. The old man put them under an upsidedown tub and paid the boy again to hit it with a spoon while he watched the worms. The boy was very excited by this, but he told the old man that the worms couldn't hear because they didn't have ears. But the old man said, "what if they have very small ears?" The boy never forgot that. He thought the old man was doddering, obviously, and everyone said so and worried about it, but the boy liked him a lot and always remembered that you didn't know if maybe the world is full of little tiny ears.
The old man did this for several years, and he even wrote a little book about worms. The Formation of Vegetable Mould Through the Action of Worms: With Observations on their Habits. He just thought it was interesting. It wasn't a very important book, but a couple of people read it and were interested in worms and that made him happy. That was the last book he wrote before he died.
The Reluctant Mr. Darwin, by David Quammen