Page:The New International Encyclopædia 1st ed. v. 05.djvu/629

CRANE. 539 CBANE. always in a V-formatron, ami the extraordinary 'clanees' with which some accompany couitshij), have Ijivn observed lor centuries and have caused a large body of myth and folklore to grow up about, the bird during classical and niedia'val times. On this point, consult C de Kay, Bird Godn (^ew York. 1808). The remote breeding of the Euro]iean crane {Orus ynis) in Lapland and along the northern border of Russia was little known until the mystery was solved by J. Wolley in 1853, who discovered among other new facts that the young run about as soon as they leave the egg, and that the sitting bird would not carry away eggs that had been handled, as had been commonly be- lieved. The birds make their nests on the ground in the marshy plains that border the Arctic Sea. The whole account (Ibis, London, 1859) is ex- ceedingly interesting, and is largely quoted by Stejneger in the Standard yatural History, vol. iv. (Boston, 1885). Other cranes of the Old W'in-ld are the nortlnxest African crowned or Balearic crane (Bafearica paroiiiiia) , which has a top-knot like that of a peacock; and the smaller Numidian crane or demoiselle {Grus rirr/o), which in summer resides and breeds from Turkey eastward to China, and which is the one most famous for its dancing. The JIanchurian crane {(Irus viridirostris) is especially common in winter in Korea., where it is trapped in large numbers and sold to the Chinese and .Tajianese, who are especially fond of it, and endow it with many folklore qtialities. The large Australasian crane {Grus Ausfralasiana) is one of the most consi)icuous birds of that region, and is known to the Australians as 'native companion' because of its friendly disposition. It will sometimes fol- low the plowman, picking up the insects he turns out of the soil. Consult Blyth, Natural History of the Cranes (London, 1881). American cranes are of three species. The greatest is the whooping crane (Grus Amcri- c-jiia), which is larger than the European crane, and is seldom seen except on the Western plains, where it has become rare. Two others are also species of the Western interior, and are diminish- ing in ntmibers; one is the sand-hill crane (Grus Mcxicana ) , and the other the little brown crane {Grus Canadensis) — both until recently regarded as one species. Consult Cones. Birds of the Xortha-est (AA'ashington, 1874). See Plate of Cranes, etc. CRANE (.S. cran, cornoch, OHG. cranuh. chraiiili. Ger. Kraiiich, crane; connected with Welsh. Corn., Bret, riaran. OChurch Slav, s/i era t'?, Lith. gfrire, Clk. y^pavoi, i/cranos, crane; so called from the resemblance of the arm of the machine to the neck of the bird). A term used in mechanics to designate a hoist which can also move the load in a horizontal or lateral di- rection. Cranes are divided into two classes, as to their motions — viz. rotary and rectilinear — and into four groups as to their motive power — viz. hand, when operated by manual power ; power, when driven by power derived from line shafting: steam, electric, hydraidic, or pneu-- matic, when driven by an engine or motor at- tached to the crane, and operated by steam, elec- tricity, water, or air transmitted to the crane from a fixed source of stipply: locomotive, when the crane is provided with its own boiler or other generator of power, and is self-propelling, usually being capable of both rotary and recti- VoL. v.— 35. linear motion. Kolary and rei'tilinear cranea are thus subdivided: (1) Swing craiu's, having rotation but no trolley motion: ('J) jib eraiu's, having rotation and a trolley traveling on the horizontal jib; (3) column cranes, identical with the jib crane, but rotating around a lixed col- umn, which usually supports a lloor or roof above; (1) derrick cranes, identical with jib cranes, except that the head of the mast is held in jiosition by guy rods, instead of by attach- ment to a roof or ceiling; (5) pillar cranes, liav- ing rotation only, the i)illar or colunui being supported entirely from the foundations; (li) pillar jib cranes, identical with the last, except in having a jib and trolley moti(m ; (7) walk- ing cranes, consisting of a pillar or jib crane mounted on wheels and arranged to travel longi- tudinally upon one or more rails; (8) locomo- tive cranes, consisting of a pillar crane mounted on a truck, and provided with a steam-engine capaljle of propelling and rotating the crane, and of hoisting and lowering the load: (9) bridge cranes, having a fixed bridge s])anning an opening and a trolley moving across the bridge; (10) tram cranes, consisting of a trunk or short bridge, traveling longitudinally on overhead rails and without trolley motion : (11) traveling cranes, consisting of a bridge, traveling longi- tudinally on overliead tracks, and a trolley mov- ing trausver.sely on the bridge; (12) gantries, consisting of an overhead bridge carried at each end by a trestle traveling on loiigiludinal tracks on the ground, and having a trollej^ moving on the bridge: (13) rotary bridge cranes, combin- ing rotary and rectilinear movements and con- sisting of a l>ridge pivoted at one end to a central pin or post and supported at the other end on a circular truck, provided with a trolley moving on the bridge. Cranes are built of wood and iron, but at the present time cast iron and steel are employed nearly exchisively. Hand cranes are employed for handling comparatively light loads, and the manual power is usually applied by means of a crank or cranks operating a windlass, around the drum of which the hoisting rope is wound and unwound. For heavy loads some form of mechanical power is always employed, which is applied through a suitable train of mechanism for performing the various movements of hoisting, rotation, and horizontal travel. A great variety of stich mechanisms are in connnon use for eacli of the principal kinds of motive power, and for details the reader should consult special treatises on hoisting machinery. Cranes are built with capacities of from a few himdrcd pounds to as much as 150 tons. The traveling crane in (he 12-inch gim shop at the Washington Navy-yard has a capacity of 150 tons; the span of the bridge is 59t^ feet; the maxinnun travel of the trolley lengthwise of the bridge is 44 feet 2 inches, and its traveling speed is from 25 to 50 feet per minute: the efl"ective lift is 40 feet, with four speeds of hoist: the speed of travel of the bridge is from 30 to 60 feet per minute. The Finnisston Qtiay. at Glasgow, Scotland, is equipped with a pillar crane of 150 tons ca- ])acity. The jib is formed of two steel tubes, each 39 inches in diameter and 90 feet long: the ra- dius of sweep for heavy lifts is 05 feet: the jib and its load are counterbalanced by a weight of 100 tons; and in a test a 130-ton load was lifted at a rate of 4 feet per minute, and a complete