Avsnitt 21

Maddie has a day out, starting by travelling on a tram. She finds out how it moves using electricity from wire cables above. Maddie jumps on board, and using her special cameras, she shows us how the tram stays in contact with the wire by making an electric circuit to give it the energy it needs. Next, Maddie finds out how maps are made . She meets a surveyor at a new housing estate, who uses a special satellite to mark new roads and houses on a map. Then she visits a mapmaking centre where they keep the Master Map and learns how cartographers make new maps of the UK.