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Thames Sailing Barge

The arms of Tower bridge had to be raised to let it through. In their heyday there were hundreds trading between the Thames and the coasts of East Anglia and Kent, sometimes further afield. The bridge would often not be raised for them - they were designed so that the mast could be quickly dropped while under sail, and they would "shoot" the bridges, relying on momentum to carry them through until they could raise the mast again. And all this with a crew of a man a boy and a dog !