Cylinder and plumbing: what they have in common

1. Step 1. Cylinder — is part of — Piston pump. The piston moves in a cylinder.
2. Step 2. Piston pump — is part of — Fire pump. A fire pump is a piston pump.
3. Step 3. Fire pump — evolved into — Fire truck. A pump on a motor-vehicle chassis.
4. Step 4. Fire truck — uses — Fire hydrant. Connection.
5. Step 5. Fire hydrant — uses — Plumbing. Plumbing.

Open Evothings