A Chain ferry is a type of water-borne ferry connecting two sides of a river between permanent landing places where the motive power is an engine pulling on a pair of fixed permanent link chains attached at each end rather than a propellor or similar mechanism.
They are very common where there is little other water-borne traffic which could get snagged in the chains, where the water may be too shallow for other options, or where they river current is too strong to permit the safe crossing of a ferry service not attached to the riverbanks.
The ferry platform uses a toothed or notched wheel to pull on the chain, lifting it from the river bed in front and dropping it back again as it crosses the river. Because of the two chains used -- one each side of the ferry - the alignment of the platform at each end of the journey is automatic and, especially for vehicle ferries, safer than a free-moving ferry might be in bad conditions.
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