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CABLES

by winding them round a special reel or drum. Hemp cables, moreover, have for long been almost wholly superseded by chain cables; the introduction of steam on board ship having brought in its train the powerful steam windlass wherewith to manipulate the heaviest chains and anchors required.

Chain cables are made in links, the length of each being generally about 6 diameters of the iron of which it is made, and the breadth about 31⁄2 diameters. There are two distinct kinds of chain cables - the stud-like chain, which has a tie or stud welded from side to side, and the short-link or unstudded chain. The cables for use in the mercantile service are made in 15-fathom lengths, but in government contracts chain cables are required to be made in 12-fathom lengths, with one swivel in the middle of every alternate length, and one joining-shackle in each length. Besides the ordinary links and joining-shackles, there are end-links, splicing-tails, mooring-swivels, and bending-swivels. The sizes of chain cables are denoted by the thickness of rod iron selected for the links. The following table gives certain ascertained quantities concerning the cables in ordinary use:

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Compared with the strength of hempen cable, a chain cable of one inch diameter of rod is equivalent to a hemp cable 102 inches in circumference; 14 inches, to 131⁄2 inches; 11⁄2 inches, to 16 inches; 134 inches, to 18 inches; and 2 inches, to 24 inches. In navigation a cable's length is a nautical measure of distance equaling 120 fathoms, or 720 feet, by which the distances of ships in a fleet are frequently estimated. This term is often misunderstood. In all marine charts a cable is deemed 607.56 feet, or one tenth of a sea mile. In rope-making the cable varies from 100 to 115 fathoms; cablet, 120 fathoms; hawser-laid, 130 fathoms, as determined by the British admiralty in 1830. According to Ure a cable's length is 100 to 140 fathoms in the merchant service. The wire rope used for submarine telegraphy is also called a cable. See CABLES, SUBMARINE.

Cables, Submarine, specially constructed ropes of wire, hemp, and gutta-percha, or other water-proofing and protecting materials, laid on ocean or river beds for the purpose of providing means of electrical communication across large bodies of water.

Until the discovery of gutta-percha such communication was impossible, as water is so good a conductor of electricity that the submersion of current-carrying wires was dependent upon complete insulation. In this gum, however, such a perfect insulator was found that submarine communication all over the world became merely a question of time, experience, and necessity. In 1843 Prof. S. F. B. Morse suggested electrical communication between the United States and Great Britain, but it was not until more than 20 years had passed

Vol. 3-22

that practical telegraphy across the Atlantic Ocean was established.

Early Cab.es.-The first under-water cables were short ones laid across rivers; later the English Channel was electrically "bridged" in this manner. In 1852 Dover and Ostend were connected by a cable 75 miles long and containing six wires. In 1854 Sweden and Denmark, Italy and Corsica, and Corsica and Sardinia were linked. In the same year the New York, Newfoundland, and London Telegraph Company was incorporated, mainly through the efforts of Cyrus W. Field and Peter Cooper, of New York, for the purpose of laying a cable between Newfoundland and Ireland, a distance of about 2,000 miles. It received a charter from the Newfoundland legislature, with an exclusive right for 50 years to establish a telegraph between the American continent and Europe via Newfoundland. In 1856 Cape Ray and Cape Breton were united, as well as Prince Edward's Island and New Brunswick. The same year Mr. Field organized the Atlantic Telegraph Company. It was supported by both the United States and British governments, but the results of its efforts were discouraging for several years. In August 1857 an attempt was made to lay a cable by the American frigate Niagara and the British ship-of-war Agamemnon, but about 300 miles from the Irish coast the cable parted, owing to a strain caused by a sudden dip of the seabottom. In 1858 the same two ships, each with half the cable on board, steamed to a point in the Atlantic midway between Valentia, Ireland, and Heart's Content, Trinity Bay, Newfoundland, spliced the cable, and, steering in opposite directions, safely landed the ends at their destinations on 5 August. The cable was 2,500 miles in length, weighed about one ton per mile, and cost $1,256,250. It was composed of seven copper wires encased in gutta-percha, which in turn was surrounded by a covering of hemp saturated with oil, pitch, and beeswax; the whole being protected by an outer sheath composed of 18 strands of seven iron wires each. cable was practically useless. The current was Despite the success in laying, however, the so weak that a message of 90 words from Queen Victoria to President Buchanan took 67 minutes to transmit, and after a few more messages the cable ceased to transmit signals. Two more cables were laid in this year to connect Great Britain with the Continent,- one to Holland and the other to Hanover; and 1859 saw, among other cable connections, the joining of England with Denmark and France, and of Malta with Sicily. In 1860 a cable was laid between France and Algiers, and in 1861 Malta was connected with Alexandria, and Batavia with Singapore. Failures were met with in attempts to lay cables through the Red Sea and from Falmouth to Gibraltar, and these, with the ill-success of the Atlantic cable, caused great disappointment to the promoters of the latter enterprise. Capital seemed to have made up its mind that a successful cable across the Atlantic was impossible. In 1865, however, another cable of 2.300 miles, and weighing 4000 tons, was shipped on the Great Eastern, and was successfully paid out for 1.065 miles from Valentia, when it broke, and was abandoned after vain attempts to grapple the lost end. The following year the Great Eastern sailed with a lighter

CABLES

but stronger cable of 2,370 miles and laid it successfully. She then grappled the lost cable of the year before, recovering it from a depth of two miles, spliced it, and completed the task by landing the end at Heart's Content.

Advance in Cable-Laying. With two cables now linking America and Great Britain, confidence was restored, and the manufacture and successful laying of submarine cables went on at a rapid rate. In 1869 a line was laid from Brest, France, to St. Pierre, Newfoundland (a distance of 3,100 miles), by a French company. In 1873 a cable joined the cities of Lisbon and Pernambuco, and in 1874 and 1875 two more cables were laid between Valentia and Heart's Content. The latter weighed less than_900 pounds per mile. Another line from Penzance, Cornwall, to St. Pierre, 2,920 miles, was laid in 1879, and one from England to Panama in 1882.

Meanwhile an incident had occurred which greatly influenced the expansion of submarine cable systems. In 1870 the British government purchased the entire land telegraph system of the British Isles, and the capital thus liberated, about $50,000,000, was largely reinvested in submarine cable ventures. In 1872 a number of small competing companies with lines through the Mediterranean were consolidated into the Eastern Telegraph Company, and in the following year the Eastern Extension, Australasian, and China Telegraph Company was formed by the amalgamation of companies owning cables farther east. Since then the Eastern, Eastern Extension, and Associated Cable companies have become practically one immense organization.

In 1884 John W. Mackey and James Gordon Bennett organized a cable system across the Atlantic from Valentia to Torbay, N. S., in the interests of the Commercial Cable Company and the New York Herald. Consolidation of competing companies followed as a matter of course, and now there are practically, besides the French lines, but two competing cable companies in the north Atlantic field-the AngloAmerican and the Commercial Cable companies. There are now 15 cables between North America and Europe, some of which run into New York harbor. The cables of 1858, 1865, and 1866 are "dead," and three others have but a brief tenure of life. Nine are "alive" and active.

Recently another great cable-laying boom has set in. France proposes to connect its colonies by a system under its own control. A German cable has been laid from Emden, Germany, to New York, via the Azores, which works in conjunction with the Commercial Cable Company. That company has recently laid its fourth cable connecting New York and London, via Canso, the Azores, and Waterville in Ireland.

Pacific Cables.- In the Pacific Ocean the Commercial Company has constructed a cable 6.912 miles long, and costing $12.000.000, laid from San Francisco, via Honolulu, the Midway Islands, and Guam. to Manila, in the Philippines, with an ultimate extension to Shanghai or Hong Kong. The first section,

from San Francisco to Honolulu. 2.413 miles, was opened 1 Jan. 1903. This section is the most hazardous on the route, depres

sions of 5,160 and 5,269 fathoms having been encountered, and the profile displaying mountains of immense elevation and valleys of corresponding depth. A level plain, with an average depth of 2,700 fathoms, extends throughout the second section, from Honolulu to the Midway Islands; the bottom being of soft mud and extremely favorable for cable-laying. Thence toward Guam an average of 3,200 fathoms is found, and favorable conditions are maintained throughout. The last section is similar in its profile to the first, though the depth averages less, being from 1,400 to 2,700 fathoms. The sea-bed is extremely irregular in outline, with many reefs and depressions.

The cable is built around a core formed of copper wire insulated by gutta-percha, around which layers of jute yarn are wound. This, in turn, is sheathed in small cables, each formed of several strands of steel wires. An outer covering of jute yarn, the whole saturated with a bituminous compound, binds together the conducting and protecting wires in one solid mass. The landing of the shore end of the cable at San Francisco was effected thus: A section of 61⁄2 miles was cut from the main cable on board the cable-steamer Silvertown, and loaded on a tender, which steamed toward the shore. On approaching the line of breakers, which were heavy, the shore end was floated on balloon buoys placed every 10 fathoms, and a team of 12 horses dragged it ashore, where it was spliced to the permanent shore conn ection, and the tender returned to the Silvertown, en board which the shore section was respliced to the main cable. The cable-ship then started for Honolulu in the evening of 14 Dec. 1902.

The Silvertown was specially built for cablelaying purposes. On this trip she carried 2.413 nautical miles of cable, weighing 4,807 tons. She arrived off Honolulu on 25 December and landed the shore end by buoying the cable; but she employed no tender or horses. Two spider-sheaves were sent ashore, and fixed by sand anchors about 60 yards apart. A haulingline was paid out from the ship, reeved through the sheaves, and brought on board again. One end of this line being attached to the cable, and the other to the picking-up gear, the engines were started and the cable was dragged toward the shore.

Another Pacific cable is being constructed jointly by the governments of Great Britain, Canada, and Australia across the Pacific from Vancouver to Fanning Island, Fiji Islands, Norfolk Island, and thence to New Zealand and Australia. It will be about 8,000 miles long, and the 3,600 mile stretch from Vancouver to Fanning Island will be the longest single section in the world. This new cable brings the Australasian colonies 10,000 miles nearer to Canada than they were before, and there is now completed a British telegraph girdle of the world which touches foreign territory only at Madeira and St. Vincent, in the Cape Verde Islands, both belonging to Britain's old ally, Portugal.

Mention has already been made of the consolidation of competing lines in the Mediterranean and the East into the Eastern Telegraph Company. To this huge organization belongs a marvelous network of submarine cables practically all the cables from Land's End, in England, through the Mediterranean to Suez,

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CABLE STEAMER "ANGLIA" LAYING SHORE
Cape Verde Islands, 10th February, 1900.

Photographed by F. B. Foy.
END OF THE NEW CAPE-OF-GOOD-HOPE CABLE AT ST. VINCENT,
This is the second section of the 15,000-mile cable line to Australia.

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