Armillary sphere and transformer: what they have in common
- Step 1. Armillary sphere — works like — Orrery. Both are mechanical models of the sky: the armillary sphere shows celestial circles, the orrery the planets' motion.
- Step 2. Orrery — evolved into — Planetarium. Models of the sky.
- Step 3. Planetarium — is made of — Concrete. Zeiss’s first dome was thin concrete.
- Step 4. Concrete — is material for — Nuclear power plant. The containment is concrete.
- Step 5. Nuclear power plant — has part — Transformer. Transformers step up the voltage so the plant's power can travel far.