252 



CORDAGE. 



COREA. 



a twist contrary to its own strands (the strands 

 in this case being right-handed, three stranded 



FIG. 6. THE LAY OF CORDAGE. 



rope). This kind of rope requires an extra 

 twist to harden it and render it impervious to 

 water, but this detracts from the strength of 

 the fiber; besides, it stretches considerably 

 under strain. Plain laid rope, moreover, con- 

 tains more yarns than hawser-laid. Their rela- 

 tive strength is as 8'7 to 6. A new process 

 gives a cord substitute for binding-wire, used 

 by farmers, of which $11,000,000 worth was 

 used in the United States in 1888. 



About $25,000,000 are invested in the manu- 

 facture of cordage in the United States. About 

 8,250 spindles are in use, including those used 

 for rope and twine. The consumption of 

 hemp is 104,000,000 pounds annually, repre- 

 senting an equal weight of the finished prod- 

 uct. It is impossible to ascertain even approxi- 

 mately the relative proportions of the different 

 sizes and qualities. 



White rope. This term is commonly applied 

 to all rope made of untarred hernp. It is the 

 strongest cordage adapted to ordinary use. 



Back-handed Rope. In this the strands are 

 given the same twist as the yarns, right-hand- 

 ed that is. Of course this must be a forced 

 process, since they tend to twist together left- 

 handed. When closed, therefore, they form a 

 left-handed rope. It is more pliable than the 

 plain laid and is less likely to kink. 



Four varieties of hard-service rope are used 

 in the United States Navy, namely, hemp, ma- 

 nila, hide, and wire. The sizes furnished in 

 the equipment of a man-of-war range from 

 1J inch (15 thread) to 10 inches inclusive. 



A rope-yarn of medium size should sustain 

 a weight of 100 pounds, but owinjr to una- 

 voidable inequalities in distributing strains the 

 strength of a finished rope can not be fairly 

 estimated by multiplying the number of yarns 

 by 100. The difference in the average strength 

 of a yarn differs with the size of the rope, thus 

 in a li-inch rope the strength for each yarn 

 may be estimated at 104 pounds, while in a 12- 

 inch rope it is equal only to 76 pounds. 



The navy rules for ascertaining the breaking 

 strain of Government rope are as follow : 



White rope or untarred hemp. Multiply the square 

 of the circumference in inches by 1371'4. 



Tarred hemp. Use 1044-9 as the multiplier. 



Manilarope. Use 783'7 as the multiplier. 



The answers will nearly equal the breaking-strain 

 in pounds. 



Iron-wire rope. Multiply the weight in pounds per 

 fathom (6 feet) by 4480. 



Steel-wire rope. Use 7098 as the multiplier. The 

 answers will be in pounds as before. 



The square of half the circumference gives the 

 breaking-strain of inferior plain laid rope in tons. 

 This is a safe rule and easy to remember ; but no 

 cordage should be subjected to a strain of more than 

 one third its estimated strength. 



To ascertain the weight of common plain laid, 

 tarred rope, multiply the square of the circumference 

 by the length in fathoms, and divide by 4'24. The 

 answer will be in pounds. 



i'OKE.l, a monarchy in eastern Asia. The 

 reigning monarch, Li-Hi, succeeded King 

 Shoal Shing in 1864. The Government is an 

 hereditary monarchy of an absolute type, 

 modeled on that of China. No important step 

 is taken in the affairs of Corea without the 

 consent of the Chinese Government. The 

 suzerainty of China has been acknowledged by 

 Corea since the seventeenth century, and the 

 dependent relation is stated in the Chinese- 

 Corean frontier trade regulations. The reve- 

 nue is principally paid in grain, and depends 

 upon the state of the harvests. In 1886 the 

 customs duties amounted to $160,278, and they 

 were estimated to exceed $200,000 in 1887. 

 There is a standing army of about 2,000 offi- 

 cers and men, constituting a royal guard, who 

 are armed mostly with breech-loading rifles. 



Area and Population. The estimated area is 

 82,000 square miles, with a population of 10,- 

 528,937, of whom 5,312,323 are males, and 

 5,216,614 females. The capital, Seoul, has 

 about 250,000 inhabitants. In 1887 there were 

 about 3,700 foreign residents in Corea, consist- 

 ing of 3,000 Japanese, 600 Chinese, and 100 

 others, mainly Germans, Americans, British, 

 French, and Russians. The language of the 

 country ia intermediate between Mongolo- 

 Tartar and Japanese. 



Commerce. The values of the imports and 

 exports for three years were as follow: 



The principal imports in 1886 were cotton 

 goods of the value of $1,300,613 ; metals, chief- 

 ly copper, $64,718; rice, $586,543; silk, 25,- 

 318; dyes and colors, $38,660; kerosene-oil, 

 $20,207. Rice is not usually an article of im- 

 port, but the deficiency caused by a bad har- 

 vest in 1885 had to be supplied from abroad. 

 The leading exports were cowhides, of the 

 value of $382,066, and beans, valued at $51,733. 

 The Government has a monopoly of the prod- 

 uct of ginseng, which is exported overland to 

 China to the value of $400,000 annually. The 

 chief agricultural products are rice, millet, 

 beans, and jute. Japan controls the greater 

 part of the foreign trade, and in 1886 imported 



