Inclined plane and bellows: what they have in common

1. Step 1. Inclined plane — evolved into — Screw. A screw is an inclined plane wrapped around a cylinder.
2. Step 2. Screw — is used in — Jack. A screw jack.
3. Step 3. Jack — has part — Check valve. Check valves.
4. Step 4. Check valve — is part of — Bellows. An air intake valve.

Open Evothings