248 



CORDAGE. 



from this material will float almost like cork, 

 and when used as a cable ascends in a rising 

 curve from the anchor to the surface of the 

 water, instead of forming a dependent or sink- 

 ing curve, as is the case with less bouyant ma- 

 terial. Fresh water rots it, but salt water ap- 

 Eears to have a preservative effect. It is still 

 irgely used by native sailors in the Indian 

 Ocean. In preparing it for manufacture, the 

 husks are soaked for some time in water and 

 then beaten to separate the fibers from the 

 dust with which they are surrounded. 



Cotton is much used for the smaller ropes, 

 rarely larger than three or four inches in cir- 

 cumference. It is comparatively weak, and 

 retains moisture to an extent that renders it 

 liable to rot. But it is easy to handle, is 

 much used under cover, and to some extent 

 on ship-board when not likely to be subjected 

 to severe strains. 



Hemp ( Cannabis sativa) of the common com- 

 mercial variety may be regarded as the rope- 

 maker's staple. Asia is the native habitat of 

 the plant, but it is now extensively cultivated 

 all over Europe, and to a considerable extent 

 in America. The plant usually matures at a 

 height of eight or ten feet, but has been known 

 to grow as high as seventeen feet. The steins 

 are dried, beaten, and crushed in a hemp-mill, 

 and then subjected to fermentation in water or 

 moisture, and afterward beaten with mallets 

 or passed through a machine called a " break." 

 The fibers are separated from the bark and 

 other waste substances, and are then hackled 

 or combed into hanks or skeins, and packed in 

 bundles of about 200 pounds each, for ship- 

 ment. Good hemp-fiber is yellowish-green, 

 smooth, glossy, and without odor. Russian 

 and Italian hemp are considered the best for 

 the general purposes of rope-making. Ameri- 

 can hemp is dark gray, and, while strong, will 

 not stand the weather so well as the European 

 varieties. 



Hair is readily made into ropes by the ordi- 

 nary processes of manufacture. It is used to 

 some extent for lariats or tether ropes, and for 

 various parts of harnesses and bridles, usually 

 in sparsely settled or uncivilized countries. 



Jute is prepared from the fibers of corchorus 

 olitorus and corchorus capsularw. The cord- 

 age is very inferior in quality, and is only used 

 when strength and durability are of no account. 

 The main use of the fiber is in coarse textile 

 fabrics, such as bagging, and floor-cloths. 



Leather or Hide. The hide is cut into strips 

 when green, and laid up by hand or by ma- 

 chinery into small rope. It is used sparingly 

 on board ship, where its toughness enables it to 

 stand friction better than hemp, but it is only 

 about one third as strong. It is also used for 

 lariats or lassos. 



Manila (Afusa textilis) is chiefly grown in the 

 Phillipine Islands, and derives its commercial 

 name from the capital town. It is often called 

 " Manila hemp," but is, in reality, derived from 

 the stalk of a species of banana. Rope made 



from this substance is more buoyant than com- 

 mon hemp ; is more pliable, causes less fric- 

 tion, and endures moisture better. Its strength, 

 when new, is about equal to that of hemp. It 

 is very extensively used by American rope- 

 makers, and has largely taken the place of 

 common hemp for maritime purposes. 



Moss. The long moss that grows on trees in 

 the Southern United States is often made up 

 into coarse rope for various uses, mainly in 

 sparsely settled regions, where it is difficult or 

 impossible to procure the commercial article. 

 It is, of course, merely a make-shift, as it pos- 

 sesses neither strength nor durability. 



Phorminin Hemp is derived from the leaves of 

 the Phormium tenax of New Zealand, a plant 

 allied to the lily family. The leaves grow to a 

 length of nine feet in their native habitat. 

 When the fibers are carefully selected, the 

 product is second only to manila for beauty 

 and strength. During the civil war in America 

 it came largely into use, mainly as an adulter- 

 ant of manila, and the inferior quality of cord- 

 age thus produced is said to have brought the 

 material into discredit. 



Silk has, at times, been made into ropes of 

 great beauty and strength, but their cost is so 

 great that they are merely articles of curiosity 

 or luxury. 



Sisal, also called "sisal hemp," is the fiber of 

 a plant closely allied to the American aloe or 

 century-plant. The commercial name refers 

 rather to the product than to the plant that 

 yields it. The fibers of the various agaves 

 are extracted from the thick leaves by pound- 

 ing. They are most familiar in the "grass" 

 hammocks commonly sold in the shops. 



Sunn Hemp (Crotolaria juncea), known also 

 as Bengal hemp. It is grown in many differ- 

 ent provinces of Hindustan and in the Sunda 

 Islands. The best comes from Comercolly, 

 and is very strong, white, and durable. It is 

 the product of a papilionaceous plant allied to 

 the pea family. 



The whole art of cordage -making rests 

 upon the mechanical principle that causes two 

 or more single hair-like fibers, when twisted 

 and laid side by side, to wind around each 

 other on being released. The familiar device 

 of twisting a piece of cord, doubling it upon 

 itself, and then allowing the two parallel parts 

 to relieve their unnatural torsion by twisting 



FIG. 1. AN EGYPTIAN ROPE-WALK, 1500 B. C. 



around each other, exhibits the fundamental 

 principle of the rope-maker's art. Long ex- 

 periment has established to a nicety the exact 

 degree of torsion necessary to secure the best 



