Apart from treadwheels, medieval depictions additionally show cranes to be powered manually by windlasses with radiating spokes, cranks and by the fifteenth century additionally by windlasses formed like a ship’s wheel. To easy out irregularities of impulse and recover from ‘dead-spots’ within the lifting process flywheels are recognized to be in use as early as 1123. During the High Middle Ages, the treadwheel crane was reintroduced on a big scale after the technology had fallen into disuse in western Europe with the demise of the Western Roman Empire. The earliest reference to a treadwheel reappears in archival literature in France about 1225, followed by an illuminated depiction in a manuscript of most likely also French origin dating to 1240. In navigation, the earliest uses of harbor cranes are documented for Utrecht in 1244, Antwerp in 1263, Brugge in 1288 and Hamburg in 1291, while in England the treadwheel is not …

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