Tonnage and poundage to be one of the complaints of his Long Parliament. The refusal of and subsequent disputes about tonnage and poundage rights is seen as one of the many events bearing responsibility for the English Civil War. Tonnage and poundage Tonnage and Poundage were certain duties and taxes first levied in Edward II's reign on every tun (cask) of imported wine, which came mostly from Spain and Portugal, and on every pound weight of merchandise exported or imported. Traditionally tonnage and poundage was granted by Parliament to the king for life until the reign of Charles I. Tonnage and poundage were
Tonnage for size, than could sailing ships. In addition to spaces taken up by boilers and steam engines, steamships carried extra fresh water for the boilers and coal for the engines. Thus, to move the same volume of cargo as a sailing ship, a steamship would be considerably larger than a sailing ship. Harbour dues are based on tonnage. In order to prevent steamships operating at a disadvantage, various tonnage calculations were established to minimize the disadvantage presented by the extra space requirements of steamships. Rather than charging by length, displacement, or the like, charges were calculated based on the viable