Tons. Deck. Beam. Proportion. {Dido 734 120 ft. 37 ft. 6 in. 3.20 English {Pilot 492 105 33 6 3.13 Navy. {Alert 358 95 30 4 3.16 American {Damascus 694 150 32 6 4.60 Merchantmen. {Rajah 531 140 30 0 4.66 These may, perhaps, be considered the extremes of ship-building; and between these there is every grade of difference. TONNAGE AND CARRIAGE OF MERCHANT VESSELS.--The amount a vessel will carry in proportion to her tonnage, depends upon whether, and to what extent, she is full or sharp built. A sharp-built vessel of 300 tons' measurement, will carry just about her tonnage of measurement goods. A sharp-built vessel of 200 tons or under would probably carry less than her measurement; if over 400 tons, she would increase gradually to fifty per cent. above her measurement. A sharp-built vessel of 600 tons, is generally rated at 900 tons carriage. A full-built vessel of 300 tons, after the latest model of American freighting vessels, will carry 525 tons, or seventy-five per cent. above her measurement; and one of 500 tons would carry full double her measurement. The following table may give a pretty fair average. TONS OF MEASUREMENT GOODS. Tonnage. Full built. Sharp built. 300 (.75) 525 (.00) 300 400 (.80) 725 (.40) 560 500 (1.00) 1000 (.50) 750 600 (1.33) 1400 (.50) 900 PROPORTIONS OF SPARS.--There is no particular rule for sparring merchant vessels; some being light, and others heavy sparred; and some having long topmasts and short lower masts, and others the reverse. The prevailing custom now is, to spar them lightly; the main yard being a little less than double the beam; and the others proportioned by the main. Most merchant vessels now have the yards at the fore and main of the same size, for convenience in shifting sails; so that the same topsail may be bent on either yard. The following table, taken from the "Seamen's Manual," will show the average proportions of the spars of merchant vessels of the largest class, as formerly built.