Ice cube trays and piston pump: what they have in common

1. Step 1. Ice cube trays — is part of — Ice machine. A tray for cubes.
2. Step 2. Ice machine — evolved into — Refrigerator. Machine-made cold.
3. Step 3. Refrigerator — is used in — Cold chain. Refrigerators.
4. Step 4. Cold chain — is used in — Vaccine. Cold storage.
5. Step 5. Vaccine — uses — Syringe. Injections.
6. Step 6. Syringe — works like — Piston pump. A syringe is a hand-operated piston pump.

Open Evothings