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THE STANDARD DICTIONARY OF FACTS 



THE GREAT SHIP CANALS OF THE WORLD 



* Minimum width, or width at bottom, given wherever possible, t Cost of construction to state. 



Caoutchouc (koo'chook), commonly called 

 India rubber, or elastic gum. A highly elastic 

 substance, obtained from the milky sap of 

 the Siphonia Elastica, and other aboraceous 

 plants. It is colorless and almost transparent 

 in the pure state, but as ordinarily met with it 

 varies from yellowish-brown to black. It is a 

 non-conductor of electricity. Its composition is 

 not definitely known; it is, nevertheless, a hy- 

 drocarbon. From its softness, impermeability 

 to water, etc., it is used in the manufacture of 

 many articles. It is easily dissolved by purified 

 naphtha obtained from coal-tar, which does not 

 change its properties, and the solution has been 

 most extensively employed to give a thin cov- 

 ering to cloth, so as to render it impervious to 

 moisture. It is also used for over-shoes, and, 

 when dissolved in oil, forms a flexible varnish. 

 Caoutchouc is principally obtained from South 

 America, whence it is usually imported in the 

 form of pear-shaped bottles, which are formed 

 by allowing the juice to flow from the tree over 

 a mould of clay, then drying by exposure to the 

 sun or to the smoke of burning fuel, after which 

 the clay in the inside is moistened with water 

 and picked out. Vulcanized India rubber. In 

 its ordinary state, India rubber becomes rigid 

 by cold, and soft by heat; hence it loses its 

 value in hot or cold countries; but when com- 

 bined with a little sulphur, at a temperature of 

 320 F. (this process, invented in this country 

 by Mr. Goodyear, being termed vulcanization), 

 it becomes highly elastic; it is not affected by 

 the most intense cold, nor by a temperature less 

 than that which is sufficient to char it ; moist- 

 ure, however long continued, seems to produce 

 no action upon it; and it is unaffected by any 

 of the ordinary solvents, such as grease, oils, 

 ether, turpentine, naphtha, or acid solutions. 

 In this state it is very largely employed in the 

 arts. Subjected to a higher degree of heat, and 

 for a longer time, it is converted into Hard India 

 rubber, Ebonite, or Vulcanite, and in this con- 

 dition it can be employed in the place of bone 

 and wood for a great number of articles, such as 

 knife-handles, combs, cups, and boxes. 



Celluloid is an artificial substance exten- 

 sively used as a substitute for ivory, bone, hard 

 rubber, coral, etc., having a close resemblance 

 to these substances in hardness, elasticity, and 

 texture. It was invented by J. W. and Isaac 

 Hyatt in 1870. It is composed of cellulose or 

 vegetable fibrine reduced by acids to pyroxyline 



(or gun-cotton), camphor is then added, and 

 the compound molded by heat and pressure 

 to the desired shape. It is used chiefly for such 

 articles as buttons, handles for knives, forks, 

 and umbrellas, billiard-balls, backs to brushes, 

 piano keys, napkin-rings, opera-glass frames, etc. 

 It can be variously colored. Manufactures of 

 celluloid now run into millions of dollars annually. 

 Charcoal, a term applied to an impure 

 variety of carbon, especially such as is produced 

 by charring wood. One kind of it is also ob- 

 tained from bones; lampblack and coke are also 

 varieties. Wood charcoal is prepared by piling 

 billets of wood in a pyramidal form, with vacu- 

 ities between them for the admission of air, and 

 causing them to burn slowly under a covering 

 of earth. In consequence of the heat, part of 

 the combustible substance is consumed, part is 

 volatilized, together with a portion of water, 

 and there remains behind the carbon of the 

 wood, retaining the form of the ligneous tissue. 

 Another process consists in heating the wood in 

 close vessels, by which the volatile parts are 

 driven off, and a charcoal remains in the retorts, 

 not so dense as that obtained by the other pro- 

 cess. Wood charcoal, well prepared, is of a 

 deep-black color, brittle and porous, tasteless 

 and inodorous. It is infusible in any heat a 

 furnace can raise ; but by the intense heat of a 

 powerful galvanic apparatus it is hardened, and 

 at length is volatilized, presenting a surface 

 with a distinct appearance of having undergone 

 fusion. Charcoal is insoluble in water, and is 

 not affected by it at low temperatures; hence, 

 wooden stakes which are to be immersed in 

 water are often charred to preserve them, and 

 the ends of posts stuck in the ground are also 

 thus treated. Owing to its peculiarly porous 

 texture, charcoal possesses the property of ab- 

 sorbing a large quantity of air or other gases at 

 common temperatures, and of yielding the 

 greater part of them when heated. Charcoal 

 likewise absorbs the odoriferous and coloring 

 principles of most animal and vegetable sub- 

 stances, and hence is a valuable deodorizer and 

 disinfectant. Water which, from having been 

 long kept in wooden vessels, as during long 

 voyages, has acquired an offensive smell, is de- 

 prived of it by filtration through charcoal pow- 

 der. Charcoal can even remove or prevent the 

 putrescence of animal matter. It is used as 

 fuel in various arts, where a strong heat is re- 

 quired, without smoke, and in various metal- 



