The next day, as soon as school was over, Arthur, Chloe, and Raymond rushed back to the library. They couldn't wait to explore the secret room again. Miss Lily met them with a twinkle in her eye. “Ready for more adventures, my little discoverers?”
They hurried to the hidden door, which Miss Lily had left ajar just for them. The dusty notebooks seemed to hum with excitement, as if they knew the children were back to visit. Raymond immediately went back to the green leather journal Arthur had found.
“Listen to this!” Raymond exclaimed, reading from a page filled with careful handwriting and simple drawings. “It says, ‘To make a tiny spark of power, one might use… lemons!’”
Chloe giggled. “Lemons? Like the sour yellow fruit we put in lemonade?” Arthur looked puzzled. “How can a lemon make electricity? That sounds like a magical trick!”
The journal explained that some liquids, like the juice in a lemon, could help make a special kind of power when mixed with certain metals. It described using shiny copper coins and silvery zinc nails, pushed into the lemons, and connected with small wires.
“It’s a simple battery!” Miss Lily explained, joining them. “Long, long ago, clever scientists figured out that if you put different metals into something juicy and a little bit sour, a tiny bit of electricity could be made. It’s like a mini-power station inside a fruit!”
A lemon battery works because acids inside the lemon create a chemical reaction between two different metals, like copper and zinc, which makes electrons flow and creates electricity.
Arthur’s eyes lit up. “Can we try it? Can we make a lemon battery?” Chloe clapped her hands. “Oh, please, Miss Lily! It sounds like so much fun!” Raymond was already sketching the diagram from the journal.
Miss Lily, always eager to encourage their curiosity, smiled. “Why, of course! This library isn't just for reading; it's for discovering! Let's gather our supplies.”
They went to the local grocery store and bought a big bag of bright yellow lemons. Miss Lily found some old copper pennies and zinc-coated nails from her workshop. And from a craft store, they got tiny wires and a very, very small light bulb, no bigger than a pea.
Back in a quiet corner of the library, the friends carefully followed the instructions. First, they rolled the lemons on the table, gently squishing the juicy insides without breaking the skin. This made the juice move around, ready for the magic.
Then, they pushed a copper penny into one side of a lemon and a zinc nail into the other side. They made sure the penny and the nail didn't touch each other inside the lemon.