Tonnages, Medieval and Modern

Datos Bibliográficos

ID3230529
AutoresFrederic C Lane (Johns Hopkins University, autor de correspondencia)
Año1964
Volumen17
Número2
Páginas213-233
Fecha de publicación1964-12-01
Peer ReviewedSí
Open AccessSí
TipoARTICLE
RevistaThe Economic History Review (JOURNAL)
Identificadores de la revistaISSN: 0013-0117 • E-ISSN: 1468-0289
EditorialWiley (PUBLISHER • GB)
DOI10.1111/j.1468-0289.1964.tb00077.x
OpenAlexW2035471057
IdiomaEN
Citas recibidas18
Referencias citadas3

onnages are of prime importance in economic history not only in estimating changes in the shipping industry's own, employment of men and resources but also in estimating the relative importance of various trade routes and the relative prosperity of various periods. To evaluate the figures used in such comparisons it is essential to know what is meant by a 'ton'. Too often historical studies refer to 'tonnage' without making clear what is meant, although the word has meanings so different one from another that a ship's tonnage measured in a ton of one kind is often two or three times its tonnage measured in a different kind of ton. The ordinary man in the street thinks first of a weight. Perhaps in America he thinks first of the short ton of 2,000 lbs., but let us hope he thinks of what is called in Britain and America the long ton of 2,240 lbs., for long tons are the measure of weight used with reference to ships. The metric ton of Iooo kg. is practically the same as the long ton (I m.t. 2,240o6 lbs. avoirdupois and I long ton oIoI6 m.t.). The best way to compare medieval and early modern statistics of shipping, it will here be argued, is to convert them as far as possible into estimates of carrying capacity measured in metric tons, or into deadweight tonnage. Since conversion is often difficult, historians are justified in repeating what they find in their sources even if they are unable to say what kind of a 'ton' is meant, so long as they make clear what they are doing. Whenever the same unit is used for all the figures in a set, comparison may be valuable within the set. Wider comparisons, however, require identification of the units used and conversion to a common denominator.1 Unfortunately different kinds of modern

Archaeology · Colonialism, slavery, and trade · Global Maritime and Colonial Histories · History · Maritime and Coastal Archaeology