Science Expo 1870
Inside ElectricityMysteries of the DeepWondrous MaterialsMarine AdvancesInvestigating Failure
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Mirror Galvanometer Morse Telegraphic Apparatus Morse Telegraphic Key and Printing Telegraph Inside Electricity

When you see lightning illuminate the heavens and scorch the earth, you are witnessing electricity -- a natural phenomenon.

We now know that electricity and magnetism are bound together, such that moving a wire across a magnetic field will create a steady electric flow. Science has brought us dynamos that can generate electricity, and telegraphs that can carry electrical signals down a wire.

Long-distance telegraphy failed at first, because electrical pulses weakened as they traveled distances or through natural elements like water. A new device, the mirror galvanometer, has solved this problem by using a reflector to detect signals.

Arc Lamp Bain Electric Clock
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