Dome and optical telegraph: what they have in common

1. Step 1. Dome — includes — Glass dome. A dome.
2. Step 2. Glass dome — has part — Mirror. A mirrored cone directs light into the hall.
3. Step 3. Mirror — is part of — Reflecting telescope. The primary mirror.
4. Step 4. Reflecting telescope — is a kind of — Telescope. A telescope.
5. Step 5. Telescope — is used in — Optical telegraph. Signals were read through a telescope.

Open Evothings