lining on the timbers at the stern, and divide the length into the same number of equal parts into which the length of the tonnage deck is divided, as above directed; measure (also at the middle of its height) the inside breadth of its space at each of the points of division, also the breadth of the stem and the breadth at the stern; number them successively 1, 2, 3, etc., commencing at the stem; multiply the second and all the other even-numbered breadths by 4, and the third and all the other odd-numbered breadths (except the first and last) by 2; to the sum of these products add the first and last breadths; multiply the whole sum by one-third of the common interval between the breadths, and the result will give in superficial feet the mean horizontal area of such space; measure the mean height of such space, and multiply by it the mean horizontal area, and the product will be the cubical contents of the space; divide this product by 100, or by 2.83 if the measurements are taken in meters, and the quotient shall be deemed to be the tonnage of such space, and shall be added to the other tonnage of the ship ascertained as aforesaid; and if the ship has more than three decks, the tonnage of each space between decks above the tonnage deck shall be severally ascertained in manner above described, and shall be added to the tonnage of the ship ascertained as aforesaid. ART. 7. If there be a break, a poop, or any other permanent closed-in space on the upper deck available for cargo or stores, or for the berthing or accommodation of passengers or crew, the tonnage of such space shall be ascertained as follows: Measure the internal mean length of such space in feet, and divide it into two equal parts; measure at the middle of its height three inside breadths, namely, one at each end and the other at the middle of the length; then to the sum of the end breadths add four times the middle breadth, and multiply the whole sum by one-third of the common interval between the breadths; the product will give the mean horizontal area of such space; then measure the mean height, and multiply by it the mean horizontal area; divide the product by 100, or by 2.83 if the measurements are taken in meters, in order to obtain the tonnage of such space. ART. 8. In measuring the length, breadth, and height of the general volume of the ship or that of the other spaces, reduce to the mean thickness the parts of the ceiling which exceed it. When the ceiling is wanting, or when it is not permanently fixed, the length and breadth are reckoned from the frame of the ship. RULE II.-For measuring the gross tonnage of laden ships. ART. 9. When ships have their cargo on board, or when for any other reason their tonnage cannot be ascertained by means of Rule I, proceed in the following manner: Measure the length on the upper deck from the outside of the outer plank at the stem to the aftside of the sternpost, deducting therefrom the distance between the aftside of the sternpost and the rabbet of the sternpost at the point where the counterplank crosses it. Measure also the greatest breadth of the ship to the outside of the outer planking or wales. Then, having first marked on the outside of the ship on both sides thereof, the height of the upper deck at the ship's sides, girt the ship at the greatest breadth in a direction perpendicular to the keel from the height so marked on the outside of the ship, on the one side, to the height so marked on the other side, by passing a chain under the keel; to half the girth thus taken add half the main breadth; square the sum, multiply the result by the length of the ship taken as aforesaid; then multiply this product by the factor 0.17 in the case of ships built of wood, and by the factor 0.18 in the case of ships built of iron. The product will give approximately the cubical contents of the ship, and the general tonnage can be ascertained by dividing by 100 or by 2.83, according as the measurements are taken in English feet or in meters. ART. 10. If there be a break, a poop, or other permanent covered and closed-in spaces (as defined in the general principles) on the upper deck, the tonnage of such spaces shall be ascertained by multiplying together the mean length, breadth, and depth of such spaces, and dividing the product by 100 or 2.83, according as the measurements are taken in English feet or meters, and the quotient so obtained shall be deemed to be the tonnage of such space, and shall be added to the other tonnage in order to determine the gross tonnage or total capacity of the ship. 61861-13- -27 DEDUCTIONS TO BE MADE FROM THE GROSS TONNAGE IN ORDER TO ASCERTAIN THE NET TONNAGE.1 ART. 11. To find from the gross tonnage of vessels as above set forth the official, or net register tonnage, either for sailing vessels or for steamships, the following mode of operation must be resorted to: SAILING VESSELS. ART. 12. For sailing vessels deduct the spaces exclusively and entirely occupied by the crew and the ship's officers, those taken up by the cookhouse and latrines exclusively used by the ship's officers and crew, whether they be situated above or below the upper deck; the covered and closed-in spaces, if there be any situated on the upper deck, and used for working the helm, the capstan, the anchor gear, and for keeping the charts, signals, and other instruments of navigation. Each of the spaces deducted as above may be limited according to the requirements and customs of each country, but the deductions must never exceed in the aggregate 5 per cent of the gross tonnage. ART. 13. The measurement of these spaces is to be effected according to the rules set forth for the measurement of covered and closed-in spaces on the upper deck; the result, obtained by deducting the total of such allowances from the gross tonnage, represents the net or register tonnage of sailing vessels. STEAMSHIPS. ART. 14. For vessels propelled by steam or any other mechanical power deduct: 1. The same spaces as for sailing vessels (art. 12) with the limitation to 5 per cent of the gross tonnage. 2. The spaces occupied by the engines, boilers, coal bunkers, shaft trunks of screw steamers, and the spaces between decks and in the covered and closed-in erections on the upper deck surrounding the funnels, and required for the introduction of air and light into the engine rooms, and for the proper working of the engines themselves. Such deductions can not exceed 50 per cent of the gross tonnage. ART. 15. The measurement of the spaces allowed for, both in sailing vessels and in steamships (sec. 1 of art. 14), is to be effected according to the rules set forth in articles 12 and 13 for sailing vessels. Spaces for which allowances are made in steamships only (sec. 2 of art. 14) are measured according to the following rules: SHIPS HAVING COAL BUNKERS WITH MOVABLE PARTITIONS. ART. 16. In ships that do not have fixed bunkers, but transverse bunkers with movable partitions, with or without lateral bunkers, measure the space occupied by the engine rooms, and add to it, for screw steamers 75 per cent, and for paddle steamers, 50 per cent of such space. By the space occupied by the engine rooms is to be understood that occupied by the engine room itself and by the boiler room together with the spaces strictly required for their working, with the addition of the space taken up by the shaft trunk in screw steamers and the spaces between decks which inclose the funnels and are necessary for the admission of air and light into the engine rooms. These spaces are measured in the following manner: Measure the mean depth of the space occupied by the engines and boilers from its crown to the ceiling at the limber strake; measure also three, or, if necessary, more than three breadths of the space at the middle of its depth, taking one of such measurements at each end and another at the middle of the length; take 1 Extract from the final report of the International Tonnage Commission assembled at Constantinople in 1873. SEC. 17. It is recommended that a penal provision shall be enacted to the effect that if any of the permanent spaces which have been deducted shall be employed either for the use of merchandise or passengers, or in any way profitably employed for earning freight, that space shall be added to the net tonnage, and never more be allowed as a deduction. the mean of such breadths; measure also the mean length of the space between the foremost and aftermost bulkheads or limits of its length, excluding such parts, if any, as are not actually occupied by or required for the proper working of the engines and boilers. Multiply together these three dimensions of length, breadth, and depth, and the product will be the cubical contents of the space below the crown. Then find the cubical contents of the space or spaces, if any, between the crown aforesaid and the uppermost or poop deck, as the case may be, which are framed in for the machinery or for the admission of light and air, by multiplying together the length, depth, and breadth thereof. Add such contents as well as those of the space occupied by the shaft trunk to the cubical contents of the space below the crown; divide the sum by 100 or by 2.83, according as the measures are taken in feet or meters and the result shall be deemed to be the tonnage corresponding to the engine and boiler room which serves as basis for the deductions referred to. If in any ship in which the space aforesaid is to be measured, the engines and boilers are fitted in separate compartments, the contents of each shall be measured separately in like manner, according to the above rules, and the sum of their several results shall be deemed to be the tonnage of the engine rooms which serves, as aforesaid, as basis for the total deductions. SHIPS WITH FIXED COAL BUNKERS. 'ART. 17. In ships with fixed coal bunkers, measure the mean length of the engine and boiler room, including the coal bunkers. Ascertain the area of three transverse sections of the ship (as set forth in the rules given in arts. 3 and 4 for the calculation of the gross tonnage) to the deck which covers the engine. One of these three sections must pass through the middle of the aforesaid length, and the two others through the two extremities. Add to the sum of the two extreme sections four times the middle one, and multiply the sum thus obtained by the third of the distance between the sections. This product divided by 100, if the measurements are taken in English feet, or by 2.83 if they are taken in meters, gives the tonnage of the space in question. If the engines, boilers, and bunkers are in separate compartments, they are separately measured, as above set forth, and the results are added together. In screw steamers the contents of the shaft trunk are measured by ascertaining the mean length, breadth, and heighth, and the product of the multiplication of these three dimensions divided by 100 or 2.83, according as the measurements are taken in English feet or in meters, gives the tonnage of such space. The tonnage of the following spaces between decks, and in the covered and closed-in erections on the upper deck, is ascertained by the same method, viz: (a) The spaces framed in round the funnels. (b) The spaces required for the admission of light and air into the engine rooms. (c) The spaces, if any, necessary for the proper working of the engines. ART. 18. Instead of the measurement of fixed bunkers, the rules for bunkers with movable partitions as set forth in article 16 may be applied. ART. 19. In the case of tugs the allowances are not limited to 50 per cent of the gross tonnage; all the spaces occupied by machinery, boilers, and coal bunkers may be deducted. Nevertheless, if such vessels are not exclusively employed as tugs, the deductions in question can not exceed 50 per cent of the gross tonnage. ADDITIONAL DEDUCTIONS ALLOWED BY THE SUEZ CANAL COMPANY. The company allows the following spaces to be included in the deductions specified at article 12 of the regulations for the measurement of tonnage, provided the deductions do not, in the aggregate, exceed 5 per cent of the gross tonnage: (a) The chart room, even when also used as the captain's cabin. When, however, the captain's accommodation comprises several rooms, one of which is the chart room, that room alone is deducted; but, in all cases, the room used as the chart room, must, if it is to be deducted, be situated on the upper deck. (b) Cabins of the ship's doctors, if actually occupied by them. (c) A mess room, if there is one, for the exclusive use of the officers and engineers; or, if they exist, two mess rooms, one of them for the exclusive use of the officers, the other one for the exclusive use of the engineers. A mess room, if there is one, for the exclusive use of the petty officers. No deduction is allowed for the officers' mess room in ships having passenger accommodation, which are not also provided with a passengers' mess room. (d) All spaces fitted as bathrooms, or lavatories, for the exclusive use of the ship's officers, engineers, and crew, with the exception of such of the said bathrooms as is available for passengers when no bathroom for their exclusive use is provided. (e) All spaces specially provided for the storage of electric searchlights and wireless telegraphy appliances, on condition that they are situated on the upper deck. The above specified spaces can only be deducted if they bear a distinctly visible and permanent indication of their exclusive appropriation. MEASUREMENT OF DECK SPACES. For vessels fitted with superstructure the following rules,' which concern only such spaces as are excluded from the national tonnage, are applied: I.-Ships with one tier of superstructures only. 1. Poop, bridge, forecastle. The following exemptions are allowed: (a) Such length of the poop measured from the inside of the stern timber, at half height of the said poop, as shall be equal to one-tenth of the full length of the ship. (b) The portion of the bridge in way of the air spaces of the engine and boiler spaces, it being understood that such air spaces are not considered to extend beyond the forward bulkhead of the stokehold and the after bulkhead of the main engine room. (c) Such length of the forecastle measured from the inside of the stem at half height of the said forecastle, as shall be equal to one-eighth of the full length of the ship. (d) In each of the above three cases of superstructures, such portions in the walls of the ships as are in way of openings not provided with any means of closing and corresponding to one another. 2. Poop and bridge combined, or forecastle and bridge combined.—In each of these combined spaces the following exemptions are allowed: (a) That length only which corresponds to the openings of the engine room and boiler spaces as specified in (b) above. (b) Such portions as are in way of openings not provided with any means of closing and corresponding to one another. 3. Shelter decks. In the case of shelter decks the portions in way of openings not provided with any means of closing and corresponding to one another. Such air spaces as are situated within the shelter deck must be measured into the engine-room space and deducted together with 75 per cent of their volume. II.—Ships having more than one tier of superstructures. (a) The exemptions prescribed in paragraphs 1, 2, and 3, above, are applicable in their entirety to the lower tier only. (b) Trers above the lower tier are only allowed the exemption of such portions as are in way of openings in the side plating of the ship not provided with any means of closing and corresponding to one another. REMARK. Should a vessel at any time transit with merchandise of any kind, or bunker coal, or stores of any description, in any portion whatever of any exempted space, the whole of that space is added to the net tonnage and can nevermore be exempted from measurement. 1 Supplementary rules added in 1904. |