Harpoon and rolling mill: what they have in common

1. Step 1. Harpoon — has part — Rope. A line connects the head to the hunter.
2. Step 2. Rope — is part of — Block and tackle. The rope runs around the pulleys.
3. Step 3. Block and tackle — is part of — Overhead crane. A block and tackle.
4. Step 4. Overhead crane — is part of — Steel works. Overhead cranes.
5. Step 5. Steel works — has part — Rolling mill. Rolling mills.

Open Evothings