Page:The New International Encyclopædia 1st ed. v. 17.djvu/200

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KOAD AND STREET MACHINERY. 180 ROADS AND RAILROADS. Stone oh Kock riiU.siiKHS are useil to hioak stone into small sizes for macadam or the upper portion of tolford roads and for use in ])reparing concrete. (See Gki.nuing and Crishi.nu JIa- rmxERY.) Screens are for separating broken .'.tnne into various sizes. (See Ore-Ukessing.) Further operations connected with getting out 'tone for road work are treated under Quarry- ing, atone-spreaders are used to distribute broken stone in layers of regular thickness on mad surfaces. The machine consists of a wagon, on which is mounted a box whose forward end may be raised to give the bottom any desired slope, and of a trailing box reaching to the ground, having a scraper attached to its bottom and rear. By adjusting this scraper the depth of the stone may be regulated at will. Sprinklers are used to moisten earth and stone used in road construction, and to lay the dust on completed streets. Their most common form is a cylindrical tank, mounted on four wheels, and with the sprinkler proper attached to the rear of the wagon. The sprinkler is a perforated tube, or tubes, adjusted to throw the water out in a snray, or shower, at the rear and sides. Sometimes special street railway cars are equipped with sprinklers, for wate/ing the por- tion of the streets between and for a little space each side of the tracks. About 1895 a street-car sprinkler was introduced which waters a half of tiie full width of the street at a time, by means of a swinging arm attached to tlie side of the car. Scrapers tor Cleaning Streets are employed to remove stiff' mud from roads and streets, and particularly from broken-stone roads. They con- sist of a series of steel or iron teeth, or long curved blades 3 to 5 inches wide, attached to a framework in such a manner that they will yield to and pass over irregularities in road and street surfaces without tearing up the stone or other material. They pile up the mud at one side. Street Sweepers of many types are employed to collect street dust and dirt for removal. Most of them consist of a revolving broom, mounted diagonally beneath and at the rear of a four- wheeled truck. The ordinary sweepers throw the dirt out to one side, in a continuous heap or row. In recent years various pick-up siceepers have been invented and to a rather limited extent introduced. Most of them throw the dirt on to a conveyor actuated by the revolutions of the axis of the wagon, and one type picks up the dirt by means of an exhaust fan, driven by an engine mounted on the machine. Nearly all the sweep- ing machines are drawn by horses, including the one just described, but toward the close of the nineteenth century the introduction of self-pro- pelled sweepers was begun. Scarifiers, for loosening the surface of macad- amized roads prior to re-surfacing, are used quite extensively in England. They consist of teeth, tines, or drills, attached to a special machine or to a road roller in such a way as to tear up the surface to a slight depth, by actions similar to plowing, drilling, or hammer blows, according to the machine. In the United States the same end is attained by fastening spikes to steam road- rollers, or by means of specially shaped plows. The use of broken stone for road surfaces de- pends very largely upon the development and use of two of the classes of machinery described in this article, road rollers and stone crushers. The first practical road roller was niade in France, in 17.S7, by .M. (le Cessart, Inspector-General of Bridges and Roads. It was made of cast iron, was three feet in diameter and eight feet wide. In 1817 a road roller was patented in England by Philip H. Clay, and in 1825 another English patent on a road roller was granted to John Biddle. Various writers place the beginnings of the continuous use of road rollers in both France and England during the period 1830-40. Some credit the French engineers with being pioneers in this respect, in 1820. Steam road rollers, Aliich have now largely replaced horse rollers where the use of the former is feasible, were first patented in France early in 1850, by Louis Le- nioine, of Bordeaux. A roller weighing ten long tons (22,400 pounds) was immediately built. It was used in Bordeaux, and in 1800 it was also used in Paris. In 1863 V. Clark, of Calcutta, India, and VV. F. Batho, of Birmingham. Eng- land, patented a steam road roller, and in 1864 .a machine built after their patent was shipped from Birmingham to Calcutta. Several other rollers of this type followed in England, the most successful of which, judging from its subsequent wide ado])tion, was that of Aveling and Porter, of Rochester, England. This firm seems to have combined, in 18(i5, a road traction engine with rollers, substituting the latter, on very broad wheels, for the ordinarv wheels of the engine. In 1867 the same finn'made a 30-ton (67.200 pounds) roller for Liverpool, a weiglit which is now considered excessive. Since 1880 several American steam rollers have been introduced. Tlie fir.st stone-crushing machine was invented by Eli Whitney Blake (q.v. ), of Connecticut, in 1852-57. It was introduced in England in 1860 and has since been used, with or without modi- fications, all over the world. It was a jaw crusher. Other types of crushers have been in- troduced since then, but few, if any, have been so extensively used. See Grinding and Crush- ing Machinery; Ore-Dressing ; Pavements; Quarry', Quarrying ; and Road. Consult: Byrne, Hifihway Construction (New York and London, 1000) ; and Aitken, Roadmakinp and Maintenance (London and Philadelphia, 1000). ROAD-RUNNER. A curious and interesting ground-cuckoo ( Oeococcyx Californianus ) of the Southwestern United States, also called 'chapar- ral-cock,' 'snake-killer,' and "paisano.' It is nearly two feet long, of which the tail is about one-half. The plumage is bronzy or coppery green, changing to dark steel blue on the head, everywhere except on the rump streaked with white or tawny: under parts soiled whitish, streaked with black on the throat, breast, and sides. The road-runner is notable for its swiftness of foot, for, aided by its wings, it is said to equal the speed of a horse. It is almost omnivorous, but reptiles and mollusks form a large part of its diet. The nest is a flimsy structure of twigs in a bush, and the white eggs are 6 to 9 in number. Like other cuckoos, the incubation begins as soon as one egg is laid, so that fresh eggs and young birds may be found in the same nest. It is said that road-runners can be domesticated, and then make very interesting pets. Another species {Geococcyx affinis) inhabits Southern Mexico and Guatemala. Consult Cooper, Birds of Cali- fornia (San Francisco, 1870). See Plate of Cuckoos. ROADS AND RAILROADS, Military. Militarv roads are of two general classes: