Ballast

33   There is no specific rule for the quantity required; as a general rule, say half the ship's tonnage, builder's measurement; see the article trim. Never take sand where stone is to be obtained; but if compelled to take it, adopt every means to prevent its entering the limbers or pumps, by protecting them with pitched canvas, matting, &c. and by caulking the ceiling, or covering it with old mats or sails. Some masters lay a trunkway each side the keelson, to allow the water to run freely to the pump-well. When sand is shipped wet, allowance must be made for drainage, by bringing the vessel well down; a cubic foot of wet sand weighs 118lb, of dry 88.6; specific gravities 1.9 and 1.42. To avoid the shifting of ballast, or even of coal, especially in sharp-built ships, when bad weather is expected, the hold is sometimes fitted with ballast stanchions and boards. The lower ends of the stanchions are set in at the keelson, and the upper lashed to the beam, a few feet from the side; five or six on each side, with planks lashed or nailed fore and aft to the stanchions, 12 or 18 inches apart; the ballast is thus divided into three portions, which prevents the possibility of shifting; the stanchions for a ship of 300 ton should be about 8 inches. The use of flat wood stanchions, as wide as the beam, may answer the same purpose, and leave more space for stowage. Sand or damp gravel should be covered with boards to receive bale goods; the dampness from sand will injure sugars or other similar goods in boxes, stowed on beds, in consequence of the settlement of the beds; it will reach and inevitably spoil lucifer matches, although stowed at a distance from it, and it stains the exterior of cases and casks -- the hoops of which are oxydized by it. With sand ballast or any similar article liable to saturation, too much reliance should not be placed on the apparent quantity of leakage indicated by the sounding rod.

34   It has been suggested by Mr. HAYWARD, LLOYDS' Agent at Madeira, that whem [sic] pumps become choked with sand ballast at sea they should be taken up and closed at foot, and that an aperture should be made at a convenient distance above, so as to draw the leakage off free from sand, which, through its specific gravity, is always most troublesome in the bottom. Capt. BRAITHWAITE of the Moodkie, took in 100 ton of sand ballast when he left Hull in December, 1860, and having encountered heavy weather, with much pumping, had not more than 60 or 65 ton left on arrival in Wingoe Sound, Norway. He attributes the safety of his ship to the height of her keelson, which prevented the sand from silting to leeward; and he determined next time to put 40 ton of stone or rubbish under the sand ballast.

35   In some Colonial and other ports sand only is to be had; and when in the tropics, it becomes so dry that it is often driven into and through the bale sacking, by the force of the wind, as the vessel rolls, much injury of the contents; it is also liable, in this state, to render the cargo quite unsafe, from the rolling and shifting which ensues; it may become necessary to make the sand more solid, by wetting it. Copper dross is sometimes used, its weight is advantageous, but it stains the cargo unless covered with plank; shingle or lead is better; the common buhr stone answers the double purpose of ballast and dunnage. Other kinds of ballast are mentioned in connection with the various articles of freight. When a ship has a cargo of light goods, such as wools, madders, cork, &c. and she is ballast with heavy goods, the freight of the latter is usually only one-third of the rate payable on a full cargo of the like description of goods. At Amsterdam a last of ballast is 2,000 lb. At Madras a load consists of 120 baskets of sand, according to a fixed price, at the average of 3½ fanams, 12 of which go to a rupee.

Transcribed by Lars Bruzelius

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