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the length, breadth, and depth of hold, the quotient is 0.72, or the coefficient of fineness.

If we now refer to Table A at 17.0ft. moulded depth, and trace the line opposite the coefficient 0.72 to the column corresponding with this depth, it is found that the winter freeboard given for a first-class steam vessel without erections, whose length is twelve times the moulded depth, is 2ft. 11in., corresponding with a reserve buoyancy of 25 per cent. of the total bulk.

9. Vessels of Extreme Proportions.-For vessels whose length is greater or less than that of the vessel of the same moulded depth for which the tables are framed, the freeboard should be increased or diminished as specified in the footnote to the tables. Thus, if the vessel in the example, clause 8, were 224ft. long, the winter freeboard required would be 2ft. 11in. plus zin., or 3ft. rin. For steam vessels coming under paragraphs 11 and 12 with enclosed erections extending over 6-10ths, or more, of the length of the vessel, the correction for length should be one-half that specified in Table A.

10. Breadth and Depth.-In framing the tables it has been assumed that the relation between the breadth and depth is such as to ensure safety at sea with the freeboard assigned when the vessel is laden with homogeneous cargo; for vessels of less relative breadth, the freeboard should be so increased as to provide a sufficient range of stability, or other means adopted to secure the same.

11. Erections on Deck.-For steam vessels with top-gallant forecastles having long poops, or raised quarter-decks connected with bridge-houses, covering in the engine and boiler openings, the latter being entered from the top, and having an efficiently constructed iron bulkhead at the fore 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 poop, or raised quarterdeck, bridge-house, and top-gallant forecastle is

95-100ths of the length of the vessel, deduct 90 per cent. of the difference between freeboards in Tables A (after correction for sheer) and Tables C.

9-10ths 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.

85-100ths 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.

8-10ths 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.

7-10ths 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.

6-10ths 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 quarterdecks 3ft. high at a length of 100ft., 4ft. high at a length of 250ft., and 6ft. high at a length of 400ft. and upwards. Intermediate lengths in proportion. For raised quarterdecks 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 cleaning 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 erections is

95-100ths 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.

90-100ths 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.

80-100ths 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.

70-100ths 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.

60-100ths of the length of the vessel, deduct 40 per cent. of the difference between the freeboards in Table A (after correction for sheer) and Tables C.

50-100ths 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). 40-100ths of the length of the vessel, deduct 25 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—

5-10ths 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). 4-10ths 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). 3-10ths of the length of the vessel, deduct 19 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 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:

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

4-8ths of the length of the vessel, deduct 32 per cent. of the difference between the freeboards in Tables A (after correction for length) and Tables C (after correction for length).

3-8ths of the length of the vessel, deduct 24 per cent. of the difference between the freeboards in Tables A (after correction for length) and Tables C (after correction for length). ·

2-8ths of the length of the vessel, deduct 16 per cent. of the difference between the freeboards in Tables A (after correction for length) and Tables C (after correction for length).

1-8th of the length of the vessel, deduct 8 per cent. of the difference between the freeboards in Tables A (after correction for length) and Tables C (after correction for length).

For erections that cover less than 1-8th of the length of the vessel, the allowance should be in proportion to that for 1-8th 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 6-10ths 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 para. 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 quarter-deck 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 6-10ths of the foregoing allowance is to he 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 erections is—

4-8ths 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.

3-8ths 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.

2-8ths 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.

1-8th of the length of the vessel, deduct 4 per cent. of the reserve buoyancy, or 6 per cent. of the freeboard required for the flushdecked vessel after correction for length. In cases where less than 1-8th of the length of the vessel is covered by erections the allowance should be in proportion to that given for erections covering 1-8th 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:

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(a) In flush-deck vessels and in vessels to which clauses 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 of or deficiency in reserve buoyancy due to variations in sheer from the standard amount over the length uncov

ered by substantial erections, as provided in the above table. Onefourth 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 of 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."

(ƒ) 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-deck vessels is greater or less 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 should depend on the extent of the main deck uncovered. This rule for round of beam does not apply to spar or awningdeck vessels.

20. As a general illustration of the way in which the tables should be used in modifying the freeboard on account of erections on deck, extreme proportions and variations in sheer, the following may be taken as an example:

A vessel is 234 ft. long, 29ft. broad, and has a moulded depth of 17ft. the coefficient of fineness being '72. Suppose the vessel to have a poop and bridge-house of the united length of 121ft., and a forecastle 20ft. in length, and let the sheer forward, measured at the side, be 4ft. 6in., and aft 2ft. 1in.

Freeboard by Tables A if of normal length, without erections, and with the normal amount of sheer

The mean she by rule is 33 4in, or 6in. less than that in the vessel, and the reduction n freeboard is 6in. divided by 4

Freeboard of vessel without erections and with 39 in. mean sheer...
Freeboard by Tables C as awning-decked

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Difference

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