Tonnage
Tonnage names 2 different subjects across the 6 encyclopedias on this shelf. Each is set out below. 1 of them is described by more than one encyclopedia.
Tonnage tun'naj, the carrying capacity of a ship
Described by 2 of the 6 encyclopedias.
Aiton's Encyclopedia (1910)
tun'naj, the carrying capacity of a ship. Wharf dues, canal tolls, pilot's fees, towage, etc., are based on the tonnage, that is, the size, not the weight, of the ship. One hundred cubic feet are considered a ton. In 1873 a congress held at Constantinople fixed rules for computing the tonnage of ships passing through the Suez Canal . Allowance is made for the space occupied by the engine room and screw shaft. Otherwise the capacity is determined by measurement of the total length and depth and average width. To this must be added storage capacity above the main deck. The total is the registered tonnage of the ship. It is made a matter of official record, so that it is not necessary to measure a ship every time the master pays canal or port dues. In ships contracting to carry freight by the ton, charges are based on the space occupied. Unless otherwise agreed, forty cubic feet of freight are reckoned a ton. In railroad offices tonnage refers to the number of tons, by weight usually, of freight transported; in shipping circles tonnage has reference to cubic capacity only. The United States government levies a port duty of six cents a ton on transoceanic steamers coming into our ports. This tax is imposed upon the carrying capacity of a ship, and the ton, as spoken of in this connection, has no reference whatever to weight. The gross tonnage of a ship includes the cubical contents of the entire closed parts of the ship--everything which is sheltered from the weather. The Lusitania, for instance, has a gross tonnage of 31,500--which is to say that her cubical contents, without any deductions, are 3,150,000 cubic feet. The tonnage tax is computed upon the net tonnage , which represents the money-earning capacity of a ship. In reckoning the net tonnage of the Lusitania, deductions are made for the space taken by quarters for officers and crew, by the boilers and machinery, and by the coal bunkers . In the Lusitania these deductions amount to 71 per cent of the ship's cubical contents, and leave 913,500 cubic feet of capacity for cargo and passengers. Consequently the net tonnage of the Lusitania is 9,135. When the Lusitania enters New York harbor she is charged six cents a ton on this net tonnage. The fee for a single entry is $548.10. The present law provides that the maximum charge for a single ship shall be the equivalent of fees for five entries, regardless of the number of calls made during the year. Accordingly, the Lusitania pays $2,740.50 each year to the United States government for the privilege of entering New York harbor. The six cent tonnage tax brought into the treasury $884,377 from 4,937 boats in the fiscal year ending in 1909. According to Lloyd's Register for 1909-10 it appears that the ocean tonnage of the world amounts to 41,449,767 tons. Of this total 36,473,102 tons represent gross tonnage of steam vessels. In the following table all countries are included whose aggregate tonnage exceeds 100,000 tons: Steamers. Tons gross. Sailing ships. Tons net. British . . . . . 17,702,714 1,123,728 United States . . . . . 3,662,332 1,291,480 German . . . . . 3,889,046 377,667 French . . . . . 1,455,976 447,617 Norwegian . . . . . 1,388,423 605,201 Japanese . . . . . 1,150,858 1,942 Italian . . . . . 961,132 358,785 Dutch . . . . . 904,536 37,704 Russian . . . . . 760,785 211,612 Swedish . . . . . 774,288 148,510 Austro-Hungarian . . . . . 744,676 5,481 Spanish . . . . . 686,875 23,143 Danish . . . . . 677,098 65,060 Belgian . . . . . 268,459 3,296 Brazilian . . . . . 222,110 20,705 Turkish . . . . . 112,849 61,895 Chilian . . . . . 106,857 40,570 Portuguese . . . . . 69,878 36,104
Collier's New Encyclopedia (1921)
in regard to ships, a measure both of cubical capacity and of dead-weight carrying capability. The term, used by itself, may have reference severally to "builders' old measurement" tonnage (B. O. M.), "register" tonnage, "displacement" tonnage, "freight" tonnage, etc., each of which expressions is more or less current in shipping circles. From very early times in the history of shipping a scale of one sort or other must have been employed to determine the relative capacity or carrying power of different vessels, and in point of fact the term "tonnage" in this connection can be traced back for at least 500 years. In Great Britain the first Act of Parliament dealing with the subject was passed in 1422, a second was introduced in 1694, and a third in 1720, but the application of these was limited to particular classes of ships, or those employed in particular trades. "Displacement" tonnage is by general consent regarded as the fairest measure for the tonnage of naval ships since they are designed to carry certain maximum weights and to float at certain load lines are fixed with reference to the nations, nations, and since 1872-prior to which date the B. O. M. rule was the only one employed the tonnage of British naval ships has been based on the displacement principle. The United States navy has also adopted displacement tonnage; in fact, it is all but universally employed. "Freight" tonnage, a system of measurement commonly employed in connection with stowage by merchants and shipowners, although it has no legal capacity, is simply a measure of cubical capacity. A freight ton, or "unit of measurement cargo," simply means 40 cubic feet of space available for cargo, and is therefore two-fifths of a register ton. In connection with yachts tonnage is measured by special rules for the purpose of regulating time allowances in racing. These rules are numerous and varied almost as the yacht clubs and associations employing them, but the rule which has hitherto been most generally adopted in Great Britain is known as the "Thames Rule," and is simply a slight modification from the B. O. M. tonnage.
Tonnage AND POUNDAGE, certain duties on wine and other merchandise
Collier's New Encyclopedia (1921)
AND POUNDAGE, certain duties on wine and other merchandise, which began to be levied in England in the reign of Edward II. They were at first granted to the crown by the vote of Parliament for a limited number of years, and renewed on their expiry. The object of these imposts was said to be that the king might have ready money in case of a sudden emergency demanding it for the defense of the realm and the Charles II. and guarding of the sea. James II. obtained grants of tonnage and poundage for life, but William III. only for limited periods; and by three statutes of Anne and George I. these imposts were made perpetual, and mortgaged for the public debt. The Customs Consolidation Act of 1787 swept away tonnage and poundage and similar charges, and substituted a new and single duty on each article.
What Has Changed in the Last Century
Aiton's 1910 rule that "one hundred cubic feet are considered a ton" was scrapped by the 1969 International Convention on Tonnage Measurement of Ships, in force since 1982: gross and net tonnage are now dimensionless numbers derived from formulas on a vessel's total volume in cubic metres, so a ship's "tonnage" no longer converts to any number of cubic feet at all. The Panama Canal adopted its own universal measurement system in 1994, though Suez still levies on its own Suez Canal Net Tonnage, the descendant of the 1873 Constantinople rules Aiton's cites. Aiton's world total of 41.4 million tons afloat in 1909-10, with Britain holding 17.7 million of it, has become a merchant fleet of well over a billion gross tons registered mostly under the flags of Panama, Liberia and the Marshall Islands. Displacement tonnage for warships and the 40-cubic-foot freight ton, both described by Collier's in 1921, survive largely unchanged, the latter now usually stated as one cubic metre.
Written for this edition, 2026.