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Show THE IDEAL ROAD. A Suiiiiiiuiy of the Ks.iay That Took the IVmisylvania l iiivi,rity l'ii.e. The first prize offered by the University Univer-sity of Pennsylvania for the best essay on road construction and maintenance was won by Engineer Henry Irwin. The Chicago Herald thus condenses it: First, as to location and construction. In the older states, where few new roads are required, Air. Irwin thinks the question ques-tion of location would generally become one of alteration and alignment, when hills are met with, rather than of complete com-plete uew location. In locating highways high-ways in hilly country it will generally be found advantageous to follow along water courses, and the advantage of having the road run close to quarries from which good road metal may be obtained ob-tained should also be kept in view. As to grades, the steepest grades that should be allowed on a public road is one in twelve, and the length of such a steep hill should not be more than 100 feet, in order that "a horse may not be overworked before reaching the top with a heavy load. A grade one in fifteen may be permitted permit-ted for about 200 feet in length, but should be avoided. A long stretch of perfectly level road should also be avoided, if possible, as surface water requires re-quires a fall of at least one in 120, or one inch in ten feet. Drainage is one of the most important items in roadmaking. It is almost impossible impos-sible to make a good road on a wet, yielding yield-ing soil, except at the expense of having hav-ing a concrete foundation. Money spent in securing a good, firm, dry : roadbed will stive a vast amount of trouble iu attempting to maintain a good surface and to keep it clean. All roads should have a ditch or drain about four feet deep on each side. Culverts to carry the drainage across the road should, if possible, be made uf stone, as timber does not last long .and the caving in of wooden culverts is a common cause of accidents. . In all cases they should be made larger than r.ulii-cient r.ulii-cient to discharge the greatest known or estimated quantity of water which has to pass through them, and 'their slope should not be less than one in 120. Small culverts up to about 2 feet 6 inches square may be built of dry stone. Across all level lands the crown of the road should be raised at least one foot above the surface of the ground; And in country roads, where extreme economy econ-omy may bo necessary, the central part of the roadway may be macadamized for a width of only eight feet, and the i entire roadway may be less than twenty feet wide, tin roads for " considerabta traffic tne macadamized portion" "should be sixteen feet wide, thus leavin g space enough for vehicles to pass-witb out always al-ways going into the same track and wearing the roadway ino ruts. -. When a bank ha.3 to bo made of soft clav u is well to lay two inch planks over tiie roadbed before placing the stone on it, a3 the clay can then consolidate consoli-date before the wood rota away sufficiently suffi-ciently to let the stones get out of level. The slopes of all cuttings or banks should be sown with grass seed to prevent pre-vent their being washed away by rain or damaged by frost. The roadbed when brought to the required grade should be rolled several times and a roller of not less than ten tons in weight should be used. If gravel is used the gravel should first be screened so as to remove all stones of more than 24 inches in diameter; the remainder should be screened again to remove all earthy matter and the small gravel which may be less than three quarters of an inch iu diameter. The gravel should be put on in layers, the bottom layer four or five inches thick and well rolled, and the next layer three or four inches, also well rolled. . If a roller is not obtainable the first layer should be allowed to remain till packed together by traffic before the second layer is spread. When ruts appear they should be immediately filled iu, and traffic directed over all parts' of the road by putting logs or large stones on the parts most traveled over till the whole surface becomes consolidated. Under the head of maintenance of roads Mr. Irwin treats at length of "Cleaning the roadbed," "Repairing the surface" and "Cleaning out the drains or water courses at the edges of the roadway." On macadamized roads, where horse machines are not nsed, hand machines, such asre used in 'Eu-rope, 'Eu-rope, are most economical. These scrapers are used by two men and are about five feet wide. Two menVith a scraper can clean more road surface than four men with hoes, as the action of the machine is continuous. It is not well to clean a macadamized road too closely or to sweep it too clean either of mud or dust, as the stone's may get loose on the surface. On the country roads, when, repaired, no road scrapings should be put on the new stone, as it will prevent it from binding and become a yielding, uneven surface. The best time to apply the stone is during wet weather in the spring and fall. The cleaning out of drains and water tables should be done in the spring beforethe spring thaw sets in, and in the fall all weeds and grass in the ditches should be cut and the culverts cul-verts and ditches left in good shape for the winter. , . The following table gives the approximate approxi-mate percentages which can he drawn on the level over various descriptions of roads as compared with what-can bo drawn on an iron track, and in itself presents an unanswerable argument for good roads. t . . c ' r - . -Per cent. Ob an iron track '. 10U On a good stone track U On asphalt 00 On bust block stone 30 On common block stone.... 20 On good Telford-Macadam t On common Macadam 13 On cobblestqna 10 On gravel over earth |