Oil lamp and voltaic pile: what they have in common
- Step 1. Oil lamp — evolved into — Incandescent light bulb. The electric lamp replaced oil and gas lamps.
- Step 2. Incandescent light bulb — is part of — Torch (flashlight). A bulb (today an LED).
- Step 3. Torch (flashlight) — has part — Dry cell. Batteries.
- Step 4. Dry cell — evolved from — Voltaic pile. A convenient form of the galvanic cell.