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of the length of the vessel, deduct 85 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

85 of the length of the vessel, deduct 80 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

1% of the length of the vessel, deduct 70 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

of the length of the vessel, deduct 55 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

1 of the length of the vessel, deduct 40 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

When the engine and boiler openings are protected only by a long raised quarter-deck, a less reduction in freeboard will be allowed.

(b) For intermediate lengths of erections the amount of the reduction in freeboard should be ascertained by interpolation.

(c) The above scale of allowance is prepared for vessels having long poops or raised quarter-decks 3 ft. high for vessels having a length of 100 ft., 4 ft. high at a length of 250 ft., and 6 ft. high at a length of 400 ft. and upwards. Intermediate lengths in proportion. For raised quarter-decks of less height the length allowed is to be in proportion to the standard of height.

(d) It is to be understood in the application of this scale of allowance for erections on deck to vessels with long poops or with raised quarter-decks and bridge-houses combined, that the deduction is a maximum deduction, applicable only to vessels of these types in which the erections are of a most substantial character, the deck openings most effectually protected, and the crew are either berthed in the bridge-house, or the arrangements to enable them to get backwards and forwards from their quarters are of a satisfactory character. For other vessels of the same class the amount of the deduction should be fixed only after a careful survey. Also such vessels when employed in the Atlantic trade will require to have specially provided greater freeboard than that given in the tables.

(e) A sufficient number of clearing ports, as large as practicable and with shutters properly hung, should be formed in the bulwarks of these vessels, between the forecastle and the bridge-house for the purpose of speedily clearing this part of the deck of water.

12. When the erections on a vessel consist of a top-gallant forecastle, a short poop having an efficient bulkhead, and bridge-house disconnected, the latter in steamers covering the engine and boiler openings and being efficiently enclosed with an iron bulkhead at each end, a deduction may be made from the freeboard given in the tables according to the following scale:

(a) When the combined length of the erection is:

100

19% of the length of the vessel, deduct 75 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

100

90 of the length of the vessel, deduct 70 per cent of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

of the length of the vessel, deduct 60 per cent of the difference between the freeboards in Tables A (after correction for sheer) and Tables C.

70% of the length of the vessel, deduct 50 per cent of the difference between the freeboards in Tables A (after correction for sheer) and Tables C.

100

60 of the length of the vessel, deduct 40 per cent of the difference between the freeboards in Tables A (after correction for sheer) and Tables C.

100

of the length of the vessel, deduct 32 per cent of the difference between the freeboards in Tables A (after correction for sheer and length) and Tables C (after correction for length).

13. When the erections on a vessel consist of a top-gallant forecastle and bridge-house only, the latter in steamers covering the engine and boiler openings and being efficiently enclosed with an iron bulkhead at each end, a deduction may be made from the freeboard given in the tables according to the following scale:

(a) When the combined length of the erections is:

of the length of the vessel, deduct 30 per cent of the difference between the freeboards in Tables A (after correction for sheer and length) and Tables C (after correction for length). of the length of the vessel, deduct 24 per cent of the difference between the freeboards in Tables A (after correction for sheer and length) and Tables C (after correction for length).

10

of the length of the vessel, deduct 10 per cent of the difference between the freeboards in Tables A (after correction for sheer and length) and Tables C (after correction for length).

14. When the erections on a steam vessel consist of a short poop or raised quarter-deck of a height not less than that laid down in paragraph 11 and top-gallant forecastle only, the

former being enclosed at the fore end with an efficient bulkhead, and when the engine and boiler openings are entirely covered either by the poop or raised quarter-deck or by a strong iron or steel deck-house enclosing the machinery casings, a deduction may be made from the freeboard given in the tables according to the following scale:

When the combined length of the erection is:

of the length of the vessel, deduct 32 per cent of the difference between the freeboards in Table A (after correction for length) and Table C (after correction for length).

of the length of the vessel, deduct 24 per cent of the difference between the freeboards in Table A (after correction for length) and Table C (after correction for length).

of the length of the vessel, deduct 16 per cent of the difference between the freeboards in Table A (after correction for length) and Table C (after correction for length).

of the length of the vessel, deduct 8 per cent of the difference between the freeboards in Table A (after correction for length) and Table C (after correction for length).

For erections which cover less than of the length of the vessel, the allowance should be in proportion to that for covered. When, however, the engine and boiler openings are not entirely covered by the poop or quarter-deck or by a strong iron or steel deck-house, the allowance for erections should be I of that provided by the foregoing scale.

15. When a steam vessel is fitted with a top-gallant forecastle only, the reduction of freeboard is to be in accordance with the preceding paragraph for a poop not covering the engine and boiler openings and a forecastle of the same combined length.

When there is a short poop only, or a raised quarter-deck of a height not less than that laid down in paragraph 11, enclosed at the forward end with an efficient bulkhead and covering the engine and boiler openings, the deduction from the freeboard is to be half the allowance that is given for a poop or quarterdeck of the same character and a forecastle having the same combined length. When the poop or raised quarter-deck does not cover the engine and boiler openings of the foregoing

allowance is to be given.

16. When the erections on a sailing vessel consist of a short poop and top-gallant forecastle only, the former enclosed at the fore-end with an efficient bulkhead, the deduction from the freeboard given in the tables should be according to the following scale:

When the combined length of the erection is:

of the length of the vessel, deduct 10 per cent of the reserve

buoyancy, or 12 per cent of the freeboard required for the flushdecked vessel after correction for length;

of the length of the vessel, deduct 8 per cent of the reserve buoyancy, or 10 per cent of the freeboard required for the vessel flush-decked after correction for length;

of the length of the vessel, deduct 6 per cent of the reserve buoyancy, or 8 per cent of the freeboard required for the vessel flush-decked after correction for length;

of the length of the vessel, deduct 4 per cent of the reserve buoyancy, or 6 per cent of the freeboard required for the flush-decked vessel after correction for length. In cases where less than of the length of the vessel is covered by erections, the allowance should be in proportion to that given for erections covering } of the length.

17. When a sailing vessel is fitted with a top-gallant forecastle only, the reduction in reserve buoyancy should be one-half that prescribed by the previous paragraph for the case where, in addition to the forecastle, the vessel is fitted with a poop of the same length. When there is a poop only, the allowance is to be half of that which in this paragraph is given for a forecastle only of the same length.

18. SHEER. The tables are framed for vessels having a mean sheer of deck measured at the side, as shown in the following table:

LENGTH OVER WHICH SHEER
IS MEASURED.

100 150 200 250 300 350 400

Mean Sheer in Inches Over the
Length Specified.

Flush-deck Vessels.-Sheer to be measured abreast stem and sternpost..

Vessels having short poops and forecastles.-Sheer to be measured at points distant the length

20 25 30 35 40 45 50

of the vessel from each end..... 14 18 22 26 30 34 38

Vessels having short forecastles only. -Sheer to be measured abreast the sternpost and at a point distant the length from the stem.

141 18 23 27 31 35 40

(a) In flush-deck vessels and in vessels to which paras. 11 and 12 apply, when the sheer of deck is greater or less than the above and is of a gradual character, divide the difference in inches between it and the mean sheer provided for by 4 and the result in inches is the amount by which the freeboard amidships should be diminished or increased according as the sheer is greater or less. (b) In vessels having short poops and forecastles, and in those having short forecastles only, the freeboard should be corrected in respect of the excess or deficiency in reserve buoyancy due to variations in sheer from the standard amount over the length uncovered by substantial erections, as provided in the above table. One-fourth the difference between the mean sheer specified and that measured as described is approximately the amount by which the freeboard should be modified in respect of sheer.

(c) The divisor 4 is to be used when the sheer is of a gradual character, and is not strictly applicable either to those cases in which the sheer is suddenly increased at the bow or stern, or to those in which it does not maintain its normal rate of increase to the ends of the vessel.

(d) In all cases the rise in sheer forward and aft is measured with reference to the deck at the middle of the length, and where the lowest point of the sheer is abaft the middle of the length, one-half the difference between the sheer amidships and the lowest point should be added to the freeboard specified in the tables for flush-deck vessels and for vessels having short poops and forecastles only.

(e) Where, as in some instances, vessels fitted with long poops or raised quarter-decks connected with bridge-houses have the deck line rising rapidly from amidships to the front of the bridge, and from that point onwards gradually approaching the normal sheer line, the freeboard may be slightly modified in consideration of the increase of height of deck in the "well."

(f) In flush-deck vessels and in vessels having short poops and forecastles the excess of sheer for which an allowance is made shall not exceed one-half the total standard mean sheer for the size of the ship.

(g) No decrease should be made in the freeboard of spar- and awning-deck vessels, in respect of excess of sheer.

19. ROUND OF BEAM. In calculating the reserve of buoyancy an allowance has been made of one-quarter of an inch for every foot of the length of the midship beam for the round up. When the round of the beam in flush-decked vessels is greater than given by this rule divide the difference in inches by 2 and diminish or increase the freeboard by this amount. For vessels with erections on deck the amount of the allowance

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