Grandpa Fenn's Workshop
The Telegraph
Long before phones, a message could cross the country in a flash. Grandpa has strung a wire from his workshop to the barn. He taps a key and the barn clicks back.
Grandpa Fenn's Workshop
Long before phones, a message could cross the country in a flash. Grandpa has strung a wire from his workshop to the barn. He taps a key and the barn clicks back.
Hold the key to send. A short press is a dot. A long press is a dash. Pause between letters.
Out in the barn, a tiny bell clicks twice. Poppy grins. Then she taps back.
A telegraph is a circuit. When the key goes down it closes the circuit. Electricity runs through the wire to the far end. A small magnet pulls a metal arm. Click.
When the key comes up the circuit opens. The click stops. A short click and a long click are all the code needs. Short is a dot. Long is a dash. Different dots and dashes make different letters.
Cut the wire and the circuit is open. The magnet never wakes up. No click, no message.
Toby taps the keyA key closes the circuit and the receiver clicks.
Dots and dashes make letters.
A cut wire means no message.
Big word for the day. Circuit. A complete path that electricity can travel around.
More machines are waiting on the bench.
Back to the Chain Reaction Bench