The Seaman's Friend. Richard Henry Dana
Placing the Masts.—For a full-built ship, take the ship's extreme length and divide it into sevenths. Place the foremast one seventh of this length from the stem; the mainmast three sevenths from the foremast, and the mizzenmast two sevenths from the mainmast. If a vessel is sharp-built, and her stem and stern-post rake, her foremast should be further aft, and her mizzenmast further forward, than the rule of sevenths would give. A common rule for placing the foremast, is to deduct three fifths of a ship's beam from her length, for the curvature of the keel forward, which is called the keel-stroke, and place the mast next abaft the keel-stroke.
Size of Anchors and Cables.—Various rules have been adopted for the weight of a ship's anchors. A vessel of 100 tons will generally have a best bower of 6 cwt. and a small bower of 5 cwt.; the weight of both being eleven pounds to a ton of the vessel. As a vessel increases in size, the proportion diminishes. A vessel of 700 tons will usually carry a best bower of 27 cwt. and a small bower of 24 cwt.; the weight of both being seven and a half pounds to a ton of the vessel. The stream should be a little more than one third the weight of the best bower. The anchor-stock should be the length of the shank; its diameter should be half that of the ring, and its thickness one inch at the middle and half an inch at each end for every foot in length. Chain cables are usually ninety fathoms in length, for large-sized vessels, and sixty for small vessels, as schooners and sloops. The regulation of the United States Navy for chain cables, is one inch and a half for a sloop of war, and one and a quarter for brigs and schooners. In the merchant service, a ship of 400 tons would probably have a best bower cable of one and five sixths, and a working bower of one and a quarter inches. A ship of 700 tons would have a best bower of one and five eighths, and a working bower of one and a half inches. Chain cables have a shackle at every fifteen fathoms, and one swivel at the first shackle. Some have two swivels; and formerly they were made with a swivel between each shackle.
Lead-lines.—The hand-lead weighs usually seven pounds, and the hand-line is from twenty to thirty fathoms in length. The deep-sea-lead (pro. dipsey) weighs from fourteen to eighteen or twenty pounds; and the deep-sea-line is from ninety to one hundred and ten fathoms. The proper way to mark a hand-line is, black leather at 2 and 3 fathoms; white rag at 5; red rag at 7; wide strip of leather, with a hole in it, at 10; and 13, 15 and 17 marked like 3, 5 and 7; two knots at 20; 3 at 30; and 4 at 40; with single pieces of cord at 25 and 35.
The deep-sea-line has one knot at 20 fathoms, and an additional knot at every 10 fathoms, with single knots at each intermediate 5 fathoms. It sometimes has a strip of leather at 10 fathoms, and from 3 to 10 is marked like the hand-line.
Log-line.—The rate of a ship's sailing is measured by a log-line and a half-minute glass. The line is marked with a knot for each mile; the real distance between each knot being, however, 1/120 of a mile, since a half-minute is 1/120 of an hour. A knot being thus the same portion of a mile that a half-minute is of an hour, the number of knots carried off while the glass is running out will show the number of miles the vessel goes in an hour. Many glasses, however, are made for twenty-eight seconds, which, of course, reduces the number of feet for a knot to forty-seven and six tenths. But as the line is liable to stretch and the glass to be affected by the weather, in order to avoid all danger of a vessel's overrunning her reckoning, and to be on the safe side, it is recommended to mark forty-five feet to a knot for a twenty-eight second glass. About ten fathoms is left unmarked next the chip, called stray-line. The object of this is that the chip may get out of the eddy under the stern, before the measuring begins. The end of the stray-line is marked by a white rag, and the first knot is forty-five or forty-seven feet from the rag. A single piece of cord or twine is put into the line for the first knot, one knot for the second, two for the fourth, three for the sixth, and so on, a single piece of cord being put in at the intermediate knots.
Ballast and Lading.—A ship's behavior, as the phrase is, depends as much upon the manner in which she is loaded and ballasted, as upon her model. It is said that a vessel may be prevented from rolling heavily, if, when the ballast is iron, it is stowed up to the floor-heads; because this will bring the ship back, after she has inclined, with less violence, and will act upon a point but little distant from the centre of gravity, and not interfere with her stiff carrying of sail. The cargo should be stowed with the weightier materials as near as possible to the centre of gravity, and