Ocean Freight Rates and Productivity, 1740–1913: The Primacy of Mechanical Invention Reaffirmed
证明19世纪新工业技术导致运费革命性下降，推翻了诺斯关于组织改进是主要节约来源的结论，指出金属船和蒸汽动力是运费下降的主因。
This article demonstrates that new industrial technology caused a revolutionary decline in nineteenth-century freight rates. This overturns Douglass North's well-known conclusion that organizational improvements were the dominant source of savings. While North's American freight rate series declines prior to the use of the metal steamship, British rates decline only modestly prior to 1850 and then rapidly as metal steamships come into use. Cotton freights dominate North's index and declined when cotton became more tightly packed for shipment. Metal ships and steam propulsion, however, caused a general decline in freight rates after 1850.