Pneumatic tube pipe and rope: what they have in common

1. Step 1. Pneumatic tube pipe — is part of — Pneumatic tube. A network of tubes between stations.
2. Step 2. Pneumatic tube — uses — Compressed air. Air pressure.
3. Step 3. Compressed air — is used in — Dental drill. Compressed air.
4. Step 4. Dental drill — works like — Electric drill. The same task — spinning a drill bit; the foot-powered dental drill appeared before the electric drill.
5. Step 5. Electric drill — evolved from — Bow drill. The oldest rotary drilling tool.
6. Step 6. Bow drill — has part — Rope. The bowstring wraps around the drill.

Open Evothings