Insulin and davy lamp: what they have in common
- Step 1. Insulin — is used in — Insulin pump. It doses insulin.
- Step 2. Insulin pump — has part — Piston. The reservoir’s plunger.
- Step 3. Piston — is part of — Newcomen engine. Atmospheric pressure moves the piston.
- Step 4. Newcomen engine — uses — Coal mine. Pumping water out of mines.
- Step 5. Coal mine — uses — Davy lamp. Protection against methane explosions.