and the shrouds should also have another set up. This is to be done only when the rigging is fresh put over the mast-head. It must be remembered, that the dead-eyes, with a shroudLaid rope, should be turned in with the sun, and with a hawserlaid rope, turned in against the sun. The lanyard must be so rove, that the end part will come up on the same side with the standing part of the shroud. It is best to keep the eyes of the shrouds as far aft on the mast-head as convenient; by which means, the foremost catharpin will be clear of the mast. A top ought to be got up side-ways, as that will render it more easy. In this case, the girtline blocks must be lashed on the fore and after part of the mast-head. The following tables will furnish much useful information respecting cordage. A Cordage table, shewing how many fathom, feet, and inches of a rope of any size under 14 inches, makes an hundred weight; with the construction of the table, and rules to calculate the weight of ropes to any large circumference. The Use of the Cordage Table. The letters I. F. F. I. at the top of the table signify Inches, Fathoms, Feet, and Inches. The first column being the girt or circumference of the rope in inches and quarters, and the other three the fathoms, feet, and inches that make up an hundred weight of such rope. One example will make it plain. Suppose I desire to know how much of a 7 inch rope will make an hundred; find the 7 in the 5th column under I. or inches girt of the rope, and against that in the 6th, 7th, and 8th columns you find 9 | 5 | 6; which shows, that in a rope of 7 inches, 9 fathom, 5 feet and 6 inches is required to make an hundred weight and so in a 9 inch rope, 6 fathoms makes an hundred weight and in a 3 inch rope 54 fathoms makes an hundred weight, &c. The construction of this table is from hence : A rope of 1 inch about required 486 fathoms to make up an hundred weight; and, as the superficial content of all circles are in proportion to the squares of their diameters, (and consequently to the squares of their circumferences) it will follow, that as a rope of 1 inch in circumference, whose square is also 1, has 486 fathoms to an hundred weight; 486 divided by the square of the circumference or girt of any other rope, the quotient will give the number of fathoms in an hundred weight. As for example, in a nine inch rope, 9 times 9 is 81, by which divide 486, the quotient is 6, the fathoms in an hundred weight: and so for a 3 inch rope, 3 times 3 is 9, by which divide 486, the quotient is 54 fathoms to an hundred weight, as in the table; and where there is a fraction in the division, it may be reduced to feet and inches; 6 feet being a fathom, and 12 inches being a foot. Suppose a cable 16 inches in circumference and 120 fathoms in length. 16 inches. 16 96 16 4)256(64 hundred weight at 112 pounds to the 24 hundred weight. 16 A table showing the Weight of any Cable or Rope of a hundred and twenty Fathoms in Length, and for every half Inch from three Inches to twenty four in circumference. I chose to instance in a cable of the length above mentioned, because yarn set at two hundred fathoms, will, in the laying of a cable, work up or shorten to a hundred and twenty fathoms ; cable laid ropes working in about two parts in five, but if it is a half cable, or a part of a cable of any other length, the weight of a hundred and twenty fathom being found by the table, the weight of any lesser part is easily found in proportion to its length. THE USE OF THE TABLE. The first column marked I. for Inches, is the thickness or circumference of the cable to every half inch from 3 to 24; the second and third, marked C. Q. for Hundreds and Quarters, are the hundreds and quarters that it will weigh if 120 fathoms in length. As for instance, suppose a cable of fourteen inches and an half; look against 144 in the fourth column, and you find against it in the other column, 52 | 2; which shews that 120 fathom of cable of 14 inches and a half about, will weigh 52 hundred two quarters, or 52 hundred and an half; and so in others. And any of a lesser length, will weigh in proportion. The construction of this table is from hence, that as all cables are solid bodies, and may properly come under the denomination of cylinders; and as such the weight of cables of any determinate length will be in proportion to the squares of their circumferences. From this foundation, experience has formed this general brief rule, viz: Multiply the thickness of the cable by itself, and one fourth of that product is the weight of 120 fathoms. As for instance, suppose a cable of 12 inches, 12 times 12 is 144, the quarter of which is 36, the weight of 120 fathom of a cable of 12 inches; as you see in the table. This table gives the utmost weight of cables of the length and size proposed, and something, though inconsiderably, differs from the foregoing. As for instance, in the foregoing table, 6 fathom of a 9 inch rope makes an hundred weight, and consequently 120 fathom should be just 20 hundred weight, but in this it makes 20 hundred and one quarter; but the difference is inconsiderable, and the cables never exceed the weight here proposed. The annexed table will be found very accurate and useful, in which every rope was weighed, or accurately estimated. Cables, of what thickness soever, are generally formed of three ropes twisted together, which are then called strands; each of these is composed of three smaller strands, and those last of a certain number of rope-yarns; this number is therefore greater or smaller, in proportion to the size of the cable required. All cables ought to be 120 fathoms in length; for which purpose, the threads or yarns must be 180 fathoms, inasmuch as they are diminished one third in length by twisting. The number of threads also of which each cable is composed being always proportioned to its length and thickness, the weight and value of it are determined by this number. Thus a cable of 10 inches in circumference ought to consist of 485 threads, and weigh 1940 lbs. and on this foundation is calculated the following table : |