Keyboard and oil well: what they have in common

1. Step 1. Keyboard — is part of — Linotype. A keyboard.
2. Step 2. Linotype — uses — Casting. It casts a line of type in metal.
3. Step 3. Casting — is used in — Cannon. Barrels were cast.
4. Step 4. Cannon — is part of — Ironclad. Artillery.
5. Step 5. Ironclad — is made of — Wrought iron. The armour is wrought iron.
6. Step 6. Wrought iron — is material for — Oil well. The casing pipes are iron.

Open Evothings