Cistern and modem: what they have in common

1. Step 1. Cistern — uses — Gutter. Water is collected from roofs and squares.
2. Step 2. Gutter — is made of — Zinc. Galvanized steel.
3. Step 3. Zinc — is material for — Dry cell. A zinc can.
4. Step 4. Dry cell — uses — Electrochemical reaction. A chemical source of current.
5. Step 5. Electrochemical reaction — is used in — Fax. The paper darkened under current.
6. Step 6. Fax — has part — Modem. It transmits an image over a telephone line.

Open Evothings