<Li> Tamzine--a fishing boat less than 15 feet (4.6 m) in length; the smallest boat to take part in the evacuation and now preserved by the Imperial War Museum . </Li> <Li> Marchioness--built in 1923, in 1989 she was involved in a collision with Bowbelle on the River Thames with the loss of 51 lives . </Li> <Li> Clan MacAlister--a 6,900 - ton cargo ship from Glasgow, Scotland . It was the largest merchant vessel used during the evacuation, and was sunk off the beach on 29 May . As it sank, it happened to settle evenly to the bottom in shallow water with the decks above water, and thereafter served as an unintentional decoy target for German Stuka dive - bombers . The British Admiralty later estimated the Clan MacAlister saved over a million pounds (sterling) worth of shipping . </Li> <P> See also individual stations for more information in many cases . </P>

How did they sink the ships in dunkirk
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