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ing (that is, within the limitations of the variations of build referred to in Tables A and B), through the intermediate element "displacement," the two Tables A and B thus establishing the mutual relations within the limits aforesaid, between builders' tonnage, gross register tonnage, and weight or cargo tonnage, with the power required to attain a given speed, thus enabling us to show the bearing of proportions of build as affecting mercantile steam transport economy.

In the first place, therefore, before entering on this exposition, and in consideration that persons generally, even amongst those who devote their time to popular and statistical studies, and to scientific pursuits, and even assume the responsibilities of legislation on shipping, are not familiar with the technical meaning of the terms "tonnage" and "burden," which are of such frequent recurrence in discussing the properties of shipping, as compared with the ordinary and unsophisticated meaning of those words, and are actually and unconsciously misled by those terms, when used technically in shipping sophistry, having a signification quite at variance with their ordinary meaning, I will endeavour to dispel this mystery by a few remarks in explanation of the terms "tonnage" and "burden," which, above all other terins, are most amenable to the foregoing singular imputation, namely, that their technical meaning is directly at variance with the ordinary signification of the said words: for example, ship's "tonnage" is not spelt with a u, "tunnage," and we all know that a "ton," as distinguished from "tun," popularly signifies 2240 lbs. weight, or 20 cwt., each cwt. being 112lbs. The ordinary accep tation of the word "ton" implies a unit of weight, not of measure. Thence it is popularly inferred that the "tonnage" of a ship means the number of tons weight which constitute the proper load of a ship; but what is a ship's tonnage as implied in the terms "tonnage O.M.," "tons burden," "register tonnage"? It has nothing whatever to do with weight. By the old law, termed "builders' measurement O.M.," which, though legally superseded in 1835, is still practically in use, and constitutes to this day the rule which, even in the Government service, generally regulates the builder's contract price of shipping, the measurement of this tonnage is regulated by the length of the ship and its breadth only, taking no cognizance of depth. It has nothing whatever to do with the load-draught of water for which a ship may be constructed. Provided that the length and breadth of two ships be the same, the builders' tonnage O.M. will be the same, though the load-draught of one ship be 30 feet and of the other only 3. This same tonnage, builders' measure O.M., is also frequently called by the equally delusive term "burden," though, as above shown, it has nothing to do with burden: for example, in shipping advertisements we see daily that "tons burden" is a designation by which ships are commonly advertised. It is true that Parliament abolished that law of tonnage, builders' measurement O.M., or the so-called "burden," in 1835, but nevertheless the Government have continued to uphold the rule (builders' measurement) as the base of their ship-building contracts, and ships, as respects their comparative size, are still only known to the world generally by their so-called tonnage or tons burden, or builders' measurement O.M. No steps having been taken by the Government to discontinue and forbid the use and adoption of the old law of measurement, though repudiated by statute in 1835, it has continued to prevail, and merchants, following the example of the Government, make it the general base of building contracts to the present day.

It is therefore submitted for the consideration of the British Association, that the statute abolition of tounage builders' measurement O.M., also called "burden," ought not to be permitted to lie dormant. It should be expressly

decreed that the said builders' measurement O.M. is not legally binding in any contract, either for the building, or freighting, or chartering of ships, and that the definition and measurement of "tonnage" shall be in accordance with the existing law, viz. the Merchant Shipping Act of 1854, subject to such amendments thereof and additions thereto as may be found necessary to render the Act complete for all the purposes of shipping registration.

And now, what is tonnage registration under the new law-the Merchant Shipping Act of 1854? To begin with: vessels constructed previously to 1854 are permitted, at the option of their owners, to retain their former tonnage or be measured under the new law, and be registered accordingly, and the statistics or Parliamentary returns of shipping do not show to what extent this privilege, of optionally withholding the former registration, has been acted upon; so that our present registration under the new law, the Act of 1854, is a mixed registration, and we do not know the ingredients thereof or their proportion; but the measurement under the new law of all ships built since May 1855, is an internal measurement, no notice whatever being taken of external measurement, or of the light draught line or constructor's load line, or any limitation thereof assigned by reference to "freeboard;" and consequently tonnage under the new law, the Act of 1854, does not give the weight-carrying capability of ships, nor any comparison thereof, if of different types of form, and of different build as respects the weight of the materials employed; but if the law does not give the weight-carrying capa bility of the ship, the question is what does it give? It gives an admissibly correct measurement of the internal capacity of ships, but calls this capacity "tonnage," giving a new signification to the word ton; for each 100 cubic feet of this internal space of the ship available for holding cargo is called a ton of tonnage. Tonnage is therefore a mere measurement of space, not of weight. Then, again, as regards cargo, even a ton of cargo is not always rated as 20 cwts. The freight of goods is charged either by measurement or by weight, and the same word "ton" is applied in all cases; 100 cubic feet constitute a ton of shipping; 40 cubic feet of some kinds of goods, and 50 feet of others, constitute a ton of measurement goods; and cargo is rated accordingly for freight, provided the said measure do not weigh a ton. 100 cubic feet of light goods may therefore be stowed in 1 ton of shipping, and be rated for freight at 2 tons; that is, a ship of 1000 tons register tonnage may be expected to stow 2500 tons of measurement cargo, or, better still, 1000 tons weight of heavy goods, and fill up with 2000 tons measurement of light cargo, and thus go to sea with this 3000 tons of freight, no limitation being assigned to draught. Such are the anomalies of tonnage, and yet we talk of statistics based on tonnage; and what is the consequence of this abuse of the word "ton"? Why, in times of war, our tonnage registration of shipping not only affords no reliable data, but actually deceives as to the capabilities of vessels for carrying ordnance and such like heavy military stores. Experience of the past three years has abundantly shown how great would be the advantage to the public if, in times-of war and emergency, when there is no time for the readmeasurement of shipping, and when shipping must be chartered or purchased at any price, our registration of shipping were available, like a tabular ready-reckoner, for giving the Government a correct idea of the capability of every ship for conveying weight of cargo, in addition to the present registration of capacity for holding cargo, and consequently a comprehensive view of the value of ships for military transport service embracing both weight and roomage. The statistical insufficiency of the present system of shipping registration as a record of the capability of ships, is shown by the following Table (A) :

Ships of 1000 tons Bds' Measure

TABLE A.-Showing approximately the extent to which the mutual relations of TONNAGE BUILDERS' MEASURE O.M., TONNAGE GROSS REGISTER NEW MEASURE under the Merchant Shipping Act of 1854, WEIGHT TONNAGE or Capability for carrying tons weight of Cargo, and LOAD DISPLACEMENT as regulated by some definite limit of Freeboard, are dependent on the proportions of Length, Breadth, and Depth that may be adopted in the construction of Ships of the same Nominal Tonnage.

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90'0 30.0

21.00 51.00 25000 20412 45412 15137 9863 77 12238 20939

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DER ON EN Register Tonnage (Gross).

Load Displacement.

**** 194 996 8963 Builders' Tonnage (O.M.).

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MUTUAL RATIOS OF TONNAGE AND LOAD DISPLACEMENT.

TONNAGE.

TONNAGE.

Bds' Measure O.M. Gross Register,

TONNAGE. Weight Tonnage,

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In this Table it will be observed that the twelve vessels, A, B, C, &c. to M, are all of the same builders' tonnage O.M., namely 1000 tons; that we have three vessels (A, B, C) whose length is four times the breadth of beam; three vessels (D, E, F) whose length is six times the breadth; three vessels (G, H, I) whose length is eight times the breadth; and three vessels (K, L, M) whose length is ten times the breadth; and that, in each set of three vessels, the load-draught of water is taken at two-thirds of the breadth, half the breadth, and one-third of the breadth; so that in this Table we have a gradation of proportions, the length varying from four times to ten times the breadth, and the load-draught varying from two-thirds to one-third of the breadth, which limits embrace nearly all the proportions of shipping in mercantile use. The arbitrary elements of construction on which the calculations (Table A) have been prosecuted, are explained in the various headings. It will be observed that the freeboard (column 5), or non-immersed depth above the load-draught line, has in each case been taken at onefortieth of the length, plus one-twelfth of the breadth of beam. There is no recognized rule for the determination of this element. Constructors of shipping follow their own rules or their own caprice in determining freeboard, or the position of the construction load-line. The above combined proportions of length and breadth have been adopted, as giving a progression, which, it is believed, will meet the ordinary allowance of freeboard at which loaded ships of all sizes are sent to sea. The various elements of construction (columns 7 to 16) are believed to be closely approximate to ordinary practice; and the ratios of nominal tonnage to actual weight-carrying capability, shown in columns 17 to 20, are therefore approximately such as would result from the ordinary build of shipping.

Now, on comparing the ratios which result from the constructive proportions of the ships A, B, C, &c., M, we have the following results:-1st, it ap pears (see columns 17 to 20), that, taking builders' tonnage at 100, the ratio of register tonnage varies from 85 to 51 in ships (A, B, C) of which the length is four times the beam, and from 94 to 63 in ships (K, L, M) of which the length is ten times the beam; that is, taking the extreme cases embraced within the limits of this Table, a ship of type K will have a register tonnage of 94 tons for every 100 tons builders' measure; but a ship of type C will have only 51 tons register for each 100 tons builders' measure. It also appears (see columns 17 and 19), with reference to builders' tonnage O.M., taken at 100, that the capability for carrying weight fluctuates from 131 tons weight down to 33 tons weight per 100 tons of builders' measure O.M., or a ship of 1000 tons builders' tonnage of the type A will have four times the weight-carrying capability that is afforded by a ship of 1000 tons builders' tonnage of the type M.

With reference to register tonnage (gross), new measure, under the Act of 1854, taken at 100, it appears (see columns 21 and 23) that the capability for carrying weight varies from 177 tons down to 52 tons per 100 tons of register tonnage; or a ship of 1000 tons gross register tonnage of the type A will have nearly 3 times the weight-carrying capability that is afforded by a ship of 1000 tons gross register tonnage of the type M.

With reference to weight tonnage, or the capability of ships to carry weight, it appears (see columns 25, 26, 27) that, with the proportions of ship A, each 100 tons of weight-carrying capability will require a vessel of 76 tons builders' measure Ö.M., or 65 tons gross register tonnage; but with the proportions of ship M, each 100 tons of weight-carrying capability will require a vessel of 303 tons builders' measure O.M., or 191 tons gross register tonnage.

With reference to the mutual relation of the load displacement and weight tonnage, it appears (see columns 29 and 32) that with the proportions of ship A, each 100 tons of load displacement will give 57 tons of weight tonnage, but with the proportions of ship M, each 100 tons of load displacement will give only 29 tons of weight tonnage; that is, a ship of 1000 tons load displacement, on the type of ship A, will carry double the weight that would be carried by 1000 tons of displacement on the type of ship M.

It might possibly be objected that the foregoing variations, which have all been calculated with reference to ships of 1000 tons builders' measure O.M., are not applicable to vessels of a different magnitude; therefore, to test the validity or otherwise of this remark, the same constructive elements have been applied to a ship X of 20,939 tons builders' measure O.M., and 25,000 tons load displacement, the length of this ship X being six times the beam, and the load-draught one-third of the beam, this type or proportion being the same as that of ship F. On comparison of the ships X and F (see columns 29, 30, 31 and 32), it will be found that the ratios of builders' tonnage, register tonnage, weight tonnage, and load displacement, are closely similar throughout: for example, in ship F, each 100 tons load displacement gives 42 tons of weight tonnage, but in ship X each 100 tons of load displacement gives 39 tons of weight tonnage. Hence we may infer that the results of these calculations, showing the extent to which the weight-carrying capabilities of ships is irrespective of the nominal tonnage, whether it be builders' tonnage O.M., or gross register tonnage N.M., and is approximately dependent on the constructor's proportions of build, admit of general application to vessels of all sizes of the types referred to in Table A. Surely the above exposition is sufficient to establish the necessity of some legislative enactment under which builders' tonnage O.M., and register tonnage N.M., should not be permitted to co-exist as recognized measurements of the mercantile capabilities of shipping. Under existing circumstances, it is respectfully submitted for the consideration of the British Association, that a clause be introduced into the Merchant Shipping Act, that the only legal signification of the word "tonnage" shall be the measurement prescribed by the said Act, and that no other signification of that term shall be legally binding in commercial transactions. Also, that the capability of ships for carrying weight, as measured with reference to some determinate freeboard, be made an item of registration.

The ratios above set forth, as expressing the weight-carrying capability of ships, include the whole weight available for engines, boilers, coal, consumable stores, and cargo; so that, as applied to steam-ships, these ratios, as respects weight-tonnage for cargo chargeable for freight, assume a new phase of great importance as affecting mercantile steam transport economy; and, for the purpose of inquiring into the modification thus introduced, the following Table B has been calculated, showing the mutual relations of displacement, power, and speed, for vessels up to 25,000 tons load displacement, the speed varying from 6 knots up to 25 knots per hour.

The element "Load Displacement" being common to both Tables A and B, we have, by the aid of these Tables combined, the means of showing the mutual relations between builders' tonnage O.M., gross register tonnage N.M., weight-tonnage, load displacement, speed, and power of all vessels within the limits of the types or proportions of build referred to in Table A, and thus showing to what an extent mercantile transport economy by steam is affected by the proportions of length, breadth, and depth to which steam ships may be built. For example: let us compare a ship of the type D, namely, length six times the beam, and load-draught two-thirds the beam,

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