Open-hearth furnace and typewriter: what they have in common

1. Step 1. Open-hearth furnace — is part of — Steel works. A steelmaking shop.
2. Step 2. Steel works — has part — Blast furnace. Blast furnaces.
3. Step 3. Blast furnace — has part — Bellows. Air was blown in by bellows, later by blowers.
4. Step 4. Bellows — is part of — Pipe organ. Bellows supply the air.
5. Step 5. Pipe organ — has part — Keyboard. Manuals were the first keyboards.
6. Step 6. Keyboard — is part of — Typewriter. The keys drive levers with type.

Open Evothings