FIGURE 3.--Forecastle. Yaa at E nage of double bottom tanks available for cargo may be obtained by multiplying the liquid-capacity weight by the proper conversion factor to get tons of 100 cubic feet. § 135.86 Portion of aggregate tonnage of hatchways. The cubical contents of hatchways shall be obtained by multiplying the length and breadth together and the product by the mean depth taken from the top of beam to the underside of the hatch cover. From the aggregate tonage of the hatchways there shall be deducted one-half of 1 percent of the vessel's gross tonnage, exclusive of hatchways, and only the remainder shall be added to the gross tonnage of the ship, exclusive of the tonnage of the hatchways. FIGURE 1.-Poop. ka a ay on and ladders leading to spaces below. national registry, provided that system is When used as smoking rooms or for any substantially similar to Moorsom sysother purposes than companion houses, tem of measurement as set forth in the parts so used shall be measured and $ $ 135.142-135.241. included in gross tonnage. § 135.142 Use of Moorsom system as set § 135.88 Domes, skylights, and air forth in this part. shafts. In countries that have not adopted the Domes, skylights, and airshafts shall Moorsom system of measuring spaces be exempt from measurement. When within vessels, the cubical contents of there is an opening in the floor of a any of the spaces included in gross tonsuperstructure immediately below a sky nage shall be ascertained according to light, the exemption shall include the the Moorsom system as set forth in the space between the skylight and the open following sections: $'$ 135.171–135.182 for ing in the floor of the superstructure im the measurement of empty vessels; mediately under the skylight. The re $'$ 135.211–135.213 for laden vessels; mainder of the superstructure shall be § 135.241 for open vessels. included in the measurement. The RULES FOR MEASUREMENT OF GROSS space, in addition to the skylight, that TONNAGE OF EMPTY VESSELS may be exempted by this section is that indicated by A, B, C, D in Figure 12, $ 135.171 Length taken tonnage which follows. deck. FIGURE 12.-Open spaces between skylight and The length for the admeasurement of opening. ships having one or more decks is taken on the tonnage deck, which is: Skylights (a) The upper deck for vessels having one or two decks. (b) The second deck from below for Rooms receiving light from Skylights vessels having more than two decks. SPACES AVAILABLE FOR PASSENGERS NOT § 135.172 Measurement of length, in TO BE EXEMPTED general. § 135.111 Spaces for use of passengers Measure the length of ship in а. not exempted. straight line along the upper side of the Spaces for the use or possible use of tonnage deck from the inside of the in ner plank (average thickness) at the passengers shall not be exempted from side of the stem to the inside of the midmeasurement except as stated in § 135.82 ship stern timber or plank there, as the case may be (average thickness) deduct$ 135.112 “Passengers" defined in case ing from this length what is due to the of army and navy auxiliary ships. rake of the bow in the thickness of the In case of army and navy transports, deck and what is due to the rake of the colliers, supply ships, and hospital ships, stern timber in the thickness of the deck, as defined in $$ 135.1–135.3, the terms and also what is due to the rake of the stern timber in one-third of the round “passengers” shall include all officers, enlisted men, and other persons who are of the beam; divide the length so taken not assigned to duty and who are not into the number of equal parts required duly inscribed on the ship's rolls. by the following table, according to the class in such table to which the ship SYSTEM FOR MEASUREMENT OF CUBICAL belongs: CONTENTS OF SPACES INCLUDED IN GROSS (a) Class 1. Ships of which the tonTONNAGE nage deck is, according to the above $ 135.141 Use of Moorsom system as ap measurement, 50 feet long or under, into plied in any country in measuring four equal parts. vessels for national registry. (b) Class 2. Ships of which the tonThe cubical contents of the spaces in nage deck is, according to the above cluded, by this part, in gross tonnage measurement, above 50 feet long and not may, in any country where the Moor exceeding 120 feet, into six equal parts. som system of measurement has been (c) Class 3. Ships of which the tonadopted, be ascertained under that sys nage deck is according to the above tem as applied in measuring vessels for measurement, above 120 feet long and (a). not exceeding 180 feet, into eight equal parts. (d) Class 4. Ships of which the tonnage deck is, according to the above measurement, above 180 feet long and not exceeding 225 feet, into 10 equal parts. (e) Class 5. Ships of which the tonnage deck is, according to the above measurement, above 225 feet long, into 12 equal parts. $ 135.173 Measurement of length in case of break in double bottom. In the case of a break or breaks in a double bottom, the length of the vessel is to be taken in parts according to the number of breaks, and each part divided into a number of equal parts according to the class in the above table to which such length belongs. § 135.174 Finding of transverse area of ship at each point of division of length. Then the hold being first sufficiently cleared to admit of the required depths and breadths being properly taken, find the transverse area of the ship at each point of division of the length or each point of division of the parts of the length, as the case may require as follows: Measure the depth at each point of division, from a point at a distance of one-third of the round of the beam below the tonnage deck, or, in the case of a break, below a line stretched in continuation thereof, to the uper side of the floor timber (upper side of the inner plating of the double bottom) at the inside of the limber strake, after deducting the average tickness of the ceiling which is between the bilge planks and the limber strake. § 135.175 Finding of transverse area of ship at each point of division of length; manner of taking depths in certain cases. In the case of a vessel contructed with longitudinal framing, the depths are to be taken to the upper edge or inner surface of the longitudinal frames, where no double bottoms exist. In the case of a ship constructed with a double bottom, the depth shall be taken to the upper side of the inner plating of the double bottom, and that upper side shall, for the purposes of measurement, be deemed to represent the floor timber of the vessel. This rule for measuring the depth of the hold applies to double-bottom ships hav ing top of double bottom not horizontal. Subject to the provisions of $ 135.85 regarding the exemption of double-bottom spaces, if any tank or compartment between the inner and outer plating of the double bottom is used or fitted for the carrying of cargo, the tonnage of the whole of such tank or compartment shall be determined and included in the gross tonnage of the vessel. § 135.176 Finding of transverse area of ship at each point of division of length. If the depth at the midship division of the length does not exceed 16 feet, divide each depth into five equal parts; then measure the inside horizontal breadth at each of the four points of division, and also at the upper point of the depth, extending each measurment to the average thickness in that part of the ceiling which is between the points of measurement. Number these breadths from above (i.e., numbering the upper breadth 1, and so on down to the fifth breadth); multiply the second and fourth by 4, and the third by 2; add these products together, and to the sum add the first breadth and the fifth. Multiply the quantity thus obtained by one-third of the common interval between the breadths, and the product shall be deemed the transverse area of the upper part of the section; then find the area between the fifth and lower point of the depth by dividing the depth between such points into four equal parts, and measure the horizontal breadths at the three points of division and also at the upper and lower points, and proceed as before, and the sum of two parts shall be deemed to be the transverse area; but if the midship depth exceed 16 feet, divide each depth into seven equal parts instead of five, and measure, as before directed, the horizontal breadths at the six points of division, and also at the upper point of the depth; number them from above, as before; multply the second, fourth, and sixth by 4, and the third and fifth by 2; add these products together, and to the sum add the first breadth and the seventh. Multiply the quantity thus obtained by one-third of the common interval between the breadths, and the product shall be deemed to be the transverse area of the upper part of the section; then find the lower part of the area as before directed, and add the two parts together, and the sum shall be deemed to be the transverse area. 265 § 135.177 Finding of transverse area of under the tonnage deck. The tonnage ship at each point of division of of this volume is obtained by dividing it length; vessels in which double bot by 100, if the measurements are taken in tom is horizontal, or in which there English feet, and by 2.83 if the measureis no double bottom. ments are taken in meters. The multiSections 135.174-135.178 apply to ves plier 0.353 may be used instead of the sels with double bottoms, the tops of divisor 2.83. which have a rise from the middle line to § 135.180 Computation of tonnage beeach side. In vessels in which the top tween decks above tonnage deck. of the double bottom is horizontal, or in If the ship has a third deck the tonwhich there is no double bottom, the nage of the space between it and the tondepths are to be divided by 4 or 6 (instead nage deck shall be ascertained as folof 5 or 7), according to whether their lows: Measure in feet the inside length midship depths do not or do exceed 16 of the space at the middle of its height feet respectively. In such cases no sub from the plank at the side of the stem to division of the lower part is to be made. the lining on the timbers at the stern, $ 135.178 Finding of transverse area of and divide the length into the same numship at each point of division of ber of equal parts into which the length length; manner of taking depths and of the tonnage deck is divided, as above breadths in certain cases. directed; measure (also at the middle of In the case of ships built on the Isher its height) the inside breadth of the wood system the depths are to be taken space at each of the points of division, to the upper edge of the longitudinal also the breadth at the stem and the frames, where no double bottom exists. breadth at the stern; number them sucIn vessels built of concrete the depths cessively 1, 2, 3, etc., commencing at the and breadths shall be taken to the inner stem; multiply the second and all the edge of the main frames. It is to be other even-numbered breadths by 4, and noted that § 135.177 provides that in ves the third and all the other odd-numsels without double bottoms no subdi bered breadths (except the first and last) vision of the lower part of the transverse by 2; to the sum of these products add area is to be made. On ships built with the first and last breadths; multiply the transverse frames without double bot whole sum by one-third of the common toms the depths are to be taken to the interval between the breadths, and the top of the transverse frames, and no result will give in superficial feet the subdivision of the lower section is neces mean horizontal area of the space; meassary. ure the mean height of the space, and multiply by it the mean horizontal area, $ 135.179 Computation of tonnage. and the product will be the cubical conNumber the transverse sections or areas tents of the space; divide this product respectively 1, 2, 3, etc., No. 1 being at the by 100 (or by 2.83 if the measurements extreme limit of the length at the bow, are taken in meters) and the quotient or of each part of the length, and the last shall be deemed to be the tonnage of number at the extreme limit of the length the space, and shall be added to the tonat the stern or the extreme limit at the after end of each part of the length; nage of the ship ascertained as aforesaid; then, whether the length be divided ac and if the ship has more than three cording to the table into 4 or 12 parts, as decks, the tonnage of each space between in classes 1 and 5, or any intermediate decks above the tonnage deck shall be number, as in classes 2, 3, and 4, multiply severally ascertained in the manner dethe second and every even-numbered scribed in this section, and shall be added area by 4, and the third and every odd to the tonnage of the ship ascertained as numbered area (except the first and aforesaid. last) by 2; add these products together, $ 135.181 Measurement of permanently and to the sum add the first and last, if covered or closed-in spaces on they yield anything; multiply the quan above upper deck. tity thus obtained by one-third of the If there be a break, a poop or any common interval between the areas, and other permanently covered or closed-in the product will be the cubical contents space on or above the upper deck (as of the space, or cubical contents of each defined in $ $ 135.61–135.63) the tonnage part if the ship is measured in parts of such space shall be ascertained as or |