Quern and rolling mill: what they have in common

1. Step 1. Quern — evolved into — Gristmill. The mill mechanized hand-turned millstones.
2. Step 2. Gristmill — uses — Water wheel. A water wheel turns the millstones.
3. Step 3. Water wheel — is used in — Rolling mill. The first mills were turned by water.

Open Evothings