S Wyatt's design 'shewing the manner of bringing the King's Beam to the ship's side by means of a floating platform or wharf, for the purpose of ascertaining the king's duties'. The Port of London was once one of the busiest trading centres in the world, with cargo ships bringing goods up the River Thames from all corners of the globe. Customs officers needed efficient methods to calculate the duty on imports. Illustration from the 'Report from the Committee Appointed to Enquire into the Best Mode of Providing Sufficient Accommodation for the Increased Trade and Shipping of the Port of London', produced by the House of Commons and published in London in 1796.
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