Moorsom System

The Moorsom System is a method created in the United Kingdom of calculating the tonnage or cargo capacity of sailing ships as a basis for assessing harbour and other vessel fees.Substantial portions of a steamship were required for boilers, machinery and coal, thus limiting the proportion of the ship's space available for cargo.In 1849, the United Kingdom appointed a Commission with Admiral George Moorsom as secretary to resolve these problems.The result was called The Moorsom System, which set forth the rules for the measurement of the internal volume of entire ship.The Commission sought to avoid a significant change in the fees charged to an existing vessel when the new system was implemented.
tonnageBuilder's Old MeasurementGross register tonnageShip measurementsLength overallLength between perpendicularsLength at the waterlineFreeboardLoad line (Plimsoll Line)Under keel clearanceAir draftGross tonnageCompensated gross tonnageNet tonnagePanama Canal/Universal Measurement SystemThames measurement tonnageNet register tonnageDeadweight tonnageTwenty-foot equivalent unitIntermodal containersDisplacementInclining testAngle of lollMetacentric height (GM)AframaxBaltimaxCapesizeChinamaxHandymax/SupramaxHandysizeMalaccamaxPanamaxPénicheSeawaymaxSuezmaxYamalmax