Unit 3Week 17

How a canal lock lifts a boat

Watch water lift a boat on the Chesapeake and Ohio Canal.

A side view of a canal lock. A mule on the towpath pulls a coal boat. The lock is a box of water between lower water and higher water, with gates at each end. lower water higher water lock towline lock keeper paddle same level! going down Water did the lifting!

Keys: Space plays or pauses. Left and right arrows move one sentence. C turns captions on or off.

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