But when the day of the ocean tramps (freighting steamers, so called) came, some scientific naval architects figured out a freeboard for them much less than the old rule of three inches of side to the foot depth of hold. The consequence was that many of these steamers sailing in the winter season went to the bottom or were never more heard of, and the death rate amongst English seamen began to multiply. The natural effect of this was the Plimsoll agitation about unseaworthy ships, resulting in the act of Parliament establishing a load mark, beyond which a captain or owner could not load his vessel without canceling his agreement with the seamen who signed articles on the ground of a freeboard satisfactory to them. It was provided by the merchant shipping act of 1875 that every British ship, upon her being entered outwards from any port in the United Kingdoin, be marked with a load. line, to be an expression of the owner's intention as to the loading of his ship for the voyage out and home. Below is a diagram illustrating freeboard marks, such as have been in use in certain steamship lines. Owners may obtain from the board of trade a maximum load-line in salt water, which is duly marked upon the sides of each vessel. In the winter season-extending from the 1st October to the 31st March-vessels must not be loaded within from 2 to 4 inches of the maximum load-line, the amount of variation to be as fixed by the board of trade in their certificates. SUMMER LOADING (April 1 to September 30).-In salt water, the summer load-line is the line (a) across the center of the disk; in fresh water, the summer load-line is indicated by the base of the letters B and T on the sides of the disk. These letters are so placed as to rest upon an imaginary line corresponding to the distances above the line (a) enumerated in column B of the table below. In summer, therefore, the steamers may be loaded in fresh water until the water touches the bottom of the letters B and T. WINTER LOADING (October 1 to March 31).-In salt water, the winter load-line is below the line (a), as in column C; in fresh water, the winter load-line is indicated by the top of the letter S on the disk, which is so placed that the upper part is suspended from an imaginary line corresponding to the distances below line (a) enumerated in column D of the table below. In winter, therefore, steamers may be loaded in fresh water until the water touches the top of the letter S. Various rules for ascertaining the freeboard that would be safe to adopt in different kinds of vessels and various trades were advanced for the benefit and guidance of ship-owners. The formulæ for some of the more important of these are given here. ** The dimensions, &c., are expressed in the formula as follows: L-length as shown by the register, B=breadth as shown by the register, D=depth of hold, T=ton nage below deck, W-weight capacity, F-freeboard in inches. First, the old Lloyd's rule depending only upon the depth of hold, may be mentioned as one of the best known. It stands as follows: For flush-decked ships: Inches of freeboard to foot depth of hold=3 or F=3 D. For spar-decked ships: 3 3D Inches freeboard to foot depth hold=or F=' 2 The old rule adopted by the surveyors of the Liverpool Underwriters' Association varied somewhat irregularly between 2.25 inches to the foot depth of hold at 10 feet and 4 inches at 26 feet. It may be expressed by the following formula: Inches freeboard to foot depth hold=12+D 10 or F (12+D) D = 10 In 1869 a modified scale was adopted for iron vessels, which may be formulated thus: D2 Second, were the rules based on other linear dimensions than depth. One of these was that suggested by the council of the Institution of Naval Architects in 1867. This rule takes mostly into account stabilility at angles of inclination. The formula for ships whose length was five breadths of beam or less is: Ships whose length was over five breadths of beam: Mr. E. Withy, ship-builder, in 1873, taking the rule of the Institution of Naval Architects as his guide, suggested the following amendments thereto. He would adhere to a system which should give every ship 30 per cent. of free-side to that portion of the hull under deck; and considering, that the longer a ship the greater the proportion of freeboard she should have, he recommended that ships of 13 to 14 depths: 5 per cent. more side inches. 14 to 15 depths: 10 per cent. more side inches. 15 to 16 depths: 15 per cent. more side inches. 16 and upwards: 20 per cent. more side inches. He would deduct for shorter vessels 12 to 11 depths: 5 per cent. more side inches. Mr. Withy advised that allowance be made for rise of sheer, and also for all water-tight deck erections. The buoyancy line may be calculated up to the lowest point of the under side of the main deck. As the inside of the hull is broader above than below the water, the percentage of space to be measured off for spare bouyancy to depend upon form. Mr. R. Duncan, ship builder, of Port Glasgow, a member of the Insti tution of Naval Architects, suggested, in 1875, that certain allowances should be made for flush-deck vessels. His formula would be: T The suggestion of Mr. Duncan applies as an amendment to the rule of the Institution of Naval Architects. The two taken and compared together afford food for consideration by those who have to study the question. As a practical example of the working of the rule propounded by the Institution of Naval Architects, the following outline may suffice to make the scale understood: For ship of 32 feet beam, 160 feet long, 4 feet freeboard; For a length of 256 feet, 7 feet freeboard; the beam remaining the same; but as the addition of a spar-deck on long vessels might be considered an equivalent or substitute for the increased freeboard required for extra length, a complete spar-deck would leave the freeboard of these extra lengths at the original height of 4 feet. Third. Of the third class of rules, which are those that attempt to take the volume of the ship as a basis, that of Mr. Moorsom, then surveyor-general of tonnage in England, is perhaps the most noteworthy. It was promulgated with a view to enable any one to estimate the dead weight capacity of vessels from their tonnage, rather than for freeboard purposes. Mr. Moorsom, twenty or thirty years ago, collected data from shipowners and masters, and, as the result of his inquiries, framed the fol lowing rule, expressing the dead weight capacity by W. Fourth. A fourth class of rules are those proposing to determine freeboard of volume by means of the relation of the registered dimensions to the registered tonnage. The idea expressed in rules of this class is that the measure of fineness of the ship may be obtained as follows, C standing for the coeffi cient of fineness: Mr. Martell, of the Lloyd's Registry of British and foreign shipping, occupied many pages of figures in the reduction of his rule. The tables for iron steamers may, it is said, be stated in the following formula: Freeboard in inches to the foot depth of hold When C equals .75 the formula becomes Freeboard in inches to foot depth of hold = 80 52-D and when C is more than .75 the sign of the last fraction is minus. Freeboard under this rule is made to depend upon two quantities, depth of hold and fineness. This holds good for ships of a length not exceeding eight times the beam. From eight to ten breadths in length the freeboard is increased by a percentage of itself thus determined: The freeboard of steamers is reduced under this rule for spar-decks and deck-houses by the use of the following fractional multipliers: For light spar-decks, . For awning-decks, fo For long poops, For short poops or long raised quarter-decks, 1 A sheer is assumed of 14 feet in 100. When there is more the sum of the excess at the ends of the vessel is divided by 12, the quotient to be deducted from the freeboard. For iron sailing vessels, the following formula gives the freeboard of the Lloyd's tables: Inches of freeboard to the foot of hold The Liverpool Registry also proposed its rules, and various other scientific institutions, but enough has been given to show how complicated this question has been, and how the doctors disagree in their diagnosis of the case. A safe rule for finding freeboard in case of iron steamers is thought to be obtained by the following formula only by a proper allowance being made for extreme length. This simple rule may be expressed as follows: "Freeboard in inches to be equal to twice the depth of hold in feet added to one fourth of the excess of length above 200 feet." But on account of the variety of types of vessels, the load-line tables of the Board of Trade and different scientific bodies were not found satisfactory, and a committee representing the Board of Trade and the ship owners and the Lloyd's Association was appointed by Mr. Chamberlain to consider whether fixed rules or tables for determining the loading of merchant ships could be adopted without unduly interfering with trade, and if So, what tables shall be adopted and what direction given to officers assigned to enforce these rules? The committee, which commenced its labors in January, 1884, after a lengthy and exhaustive investigation of the whole subject, have come to the unanimous conclusion that the use of fixed tables may be enforced without unfair interference with the operations of trade, and have adopted four sets of tables for adjusting a freeboard for flush-deck, spar-deck, and awning-decked steamers, and for sailing vessels. The committee are said to be of opinion that in applying the tables prepared for the different classes of ships, the exercise of good judgment will be necessary in dealing with vessels of inferior quality, or in poor condition, or with those of peculiar or extraordinary build. The principle is to be insisted on that inferior vessels shall not undergo more strain to the square inch, amidships, than that which the material of first-class ships have to undergo. The Lloyd's Register and the Liverpool Register have recently amalgamated, and the society whose indorsement would be necessary, are said to favor the conclusions of the new load line committee, so that it may be said that the recommendations are practically adopted. Annexed are the new freeboard tables: DEFINITIONS. Length. The length of the vessel is measured on the load-line from the fore side of the stem to the aft side of the stern-post in sailing vessels, and to the aft side of the after post in steamers. Breadth.-The breadth used in obtaining the cofficient of fineness is the extreme breadth measured to the outside of plank or plating as given in the register book, or on the certificate of the ship's registry. Depth of hold. The depth used in obtaining the coefficient of fineness is the depth of hold as given in the register book, or on the certificate of the ship's registry. This dimension is subject to modification in determining the coefficient of fineness as explained in clause 4. Coefficient of fineness.-The coefficient of fineness in one, two, and three deck and spar-deck vessels is found by dividing 100 times the gross registered tonnage of the vessel below the upper deck by the product of the length, breadth, and depth of hold. In awning-deck vessels the registered depth and tonnage are taken below the main deck. Molded dep h.-The molded depth of an iron or steel vessel, as given in the tables, is the perpendicular depth taken from the top of the upper deck beam at side, at the middle of the length of the vessel, to the top of the keel and the bottom of the frame at the middle line, except in spar and awning deck vessels, in which the depth is measured from the top of the main-deck beams. In wooden and composite vessels the molded depth is taken to be the perpendicular depth from the top of the upper deck beam at the side of the vessel amidships to the lower edge of the rabbet of the keel. The form at the lower port of the midship transverse section of many wooden and composite vessels being of a hollow character, as in cases where thick garboard strakes are litted, the molded depth in such instances should be measured from the point where the line of the flat of the bottom continued cuts the keel. Freeboard. -The molded depth, taken as above described, is that used in the tables for ascertaining the amount of reserve buoyancy and corresponding freeboard in vessels having a wood deck, and the freeboard is measured from the top of the wood deck at side, at the middle of the length of the vessel. EXPLANATION. In the following tables the word “freeboard" denotes the height of the side of a ship above the water-line at the mid lle of her length, measured from the top of the deck at the side, or, in cases where a water-way is fitted, from the curved line of the top of the deck contiuned through to the side. The freeboards and the corresponding percentages of reserve buoyancy necessary for flush-deck steamers not having spar or awning decks, for awning-deck steamers, and for flash-deck sailing vessels, are given in Tables A, C, and D for vessels of these classes and of various dimensions and proportions. The freeboards necessary for spir-deck steamers are given in Tables B. The latter are determined by cons derations of structural strength, and they denote the limitations to depth of loading which are thereby imposed upon first-class vessels of this type. The freeboards aul percentages of reserve buoyancy thus obtained being in excess of what would otherwise be required, the amounts of such percentages are not given in Tables B. The exact freeboard required for a given ship belonging to any of the classes comprised in Tables A, C, and D, may be calculated by constructing a displacement scale to the height of the deck to which the freeboard is measured, so as to give the whole external volume up to the upper surface of that deck. The percentage of the total |