Page:Collier's New Encyclopedia v. 08.djvu/92

LEFT ROADS 66 ROANOKE with a movable scraper, by means of dation is obtained the laying of a base, which the depth of stones may be reg- the best material being concrete of grav- ulated. el and lime, gives durability to the road. Sprinklers are used for spreading wa- On this base the actual roadway is laid ter, oils and various tarry preparations with a slight inclination from the center on the surface of roads, in order to lay to the sides for the purpose of drainage, dust and produce a more even and less Before the time of Macadam it was cus- easily pulverized surface. They consist tomary to use broken stones of different of a tank, mounted on wheels, carrying sizes to form the roadway, the conse- a perforated pipe behind. Modern sprin- quence being that in course of time the klers are sometimes fitted with steam smaller stones sank, making the road boilers for heating the liquid, and with rough and dangerous. Macadam early air compressors, by means of which the in the 19th century (see Macadam) in- material may be forced through nozzles troduced the principle of using stones fn a spray. of uniform size from top to bottom. The Sweepers and Scrapers, used in clean- general superintendence of roadways is Ing streets, are of various types. The usually exercised by the government of a sweepers usually consist of a cylindrical country, but it intrusts the execution brush, which revolves as the framework of its enactments to local authorities, on which it is mounted is hauled along. Highways are public roads which every More elaborate machines pick up the citizen has a right to use. They are dirt as it is swept by the brush, some constituted by prescription, by act of leg- by means of a conveyor, others by means islature, or by dedication to the public of a suction device, similar to the well- use. What is known as the rule of the known vacuum cleaner. Most of these road is that in passing other horsemen machines are horse drawn, but motor or carriages, whether going in the same vehicles are also in use. Scrapers may or the opposite direction, the rider or consist of a row of curved blades at- driver must pass on the right hand of tached to movable rods which enable the the other rider or driver. Automobiles blades to yield to irregularities in the and bicycles are subject to the same re- surface of the road. Small, manual strictions and are entitled to the same types are familiar, as well as larger privileges as ordinary vehicles, horse-drawn machines. _, _, . ______ _, . x, , Scarifiers are used in loosening the ROANNE France, a town m the de- surface of macadam roads, when under partment of the Loire, important as a repair. They are of various patterns, railroad junction, situated on the left but consist essentially of metal spikes bank of the Loire, 42 miles N. W. of which scrape or drill into the road to a Lyons. In connection with the railroads depth sufficient to loosen the surface. lar £e machine shops and engineering The spikes are sometimes fixed to the works. are located here. Other impor- f ront of steam rollers. * ant. industries are copper and iron foundries, dye works, and textile mills. ROADS, artificial pathways formed Pop. about 37,000. through a country for the accommoda- BOANOKE, a city in Roanoke co., tion of travelers and the carriage of Va-. on the Ro anoke ri ver, and on the commodities. Though the Romans set Norfo i k and Western and Virginian rail- an example as road-builders, some of roads; 56 miles W- of Lynchburg. It their public highways being yet service- is in a section rich in iron mining and able, the roads throughout most of Eu- f arm mg interests. Here are a high rope were m a wretched condition till school> the Virginia College (women) toward the > end of the 18th century. Re bekah Sanitarium and six hospitals- France was in advance of other countries i mproV ed sewer system, waterworks, in road making; m England a decided street rai]road and electric light plants, improvement of the highways only began Nat i nal and State banks, several ho- rn the 19th century. When diversities tels? and dailv> wee kly, and monthly of level are necessary, road engineers fix periodicals. It has large machine shops, the degree of inclination at the lowest ro ]ii n g m in S) Dott le works, tobacco fac- possible point. Telford estimated the tories? locomotive and car works, iron maximum inclination of a road to be 1 and steel wor ks, canning factories, spoke m 24 but, except in extreme cases, it vs f acto ries, saw and planing mills, coffee considered better that it should not ex- and snice mills> and many sma n er in- ceedl m 50. The angle of repose, or dustr ies. Potj. (1910) 34,874; (1920) maximum slope on which a carriage will qq g^. stand, has been estimated at 1 in 40. A properly constructed road, besides a ROANOKE, a river of the United foundation, consists of two layers, an States, in Virginia and North Carolina, upper and an under. After a good foun- It flows chiefly S. E., and after a course