Inductor and telescope: what they have in common

1. Step 1. Inductor — has part — Copper wire. A winding.
2. Step 2. Copper wire — is part of — Electrical telegraph. Communication lines.
3. Step 3. Electrical telegraph — evolved from — Optical telegraph. The electrical telegraph replaced semaphore lines.
4. Step 4. Optical telegraph — uses — Telescope. Signals were read through a telescope.

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