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Show ROAD MODELS The exhibit of road models shown for ; the first time in 1909 by the Office of ' Public Roads in the department at the ' Alaska-Yukon-Pacific Exposition has been in active service ever since. Hundreds Hun-dreds of thousands of people have seen these models at a dozen or more of the big agricultural expositions, and they have traveled much of the length and '. breadth of the United States on demonstration demon-stration trains. A comprehensive ex-! i hibit is now being made at the Panama-1 Pacific Exposition at San Francisco, Cal. People who have seen these miniature min-iature model roads not only appreciate the beneficent effects of improved roads but at the same time understand the methods of their- construction. In order that these models may have a still greater usefulness, they have been photographed and form the basis of illustrations il-lustrations of a United States Department Depart-ment of Agriculture Bulletin No. 220, "Road Models." The models, as a rule, are constructed construct-ed on a scale of one inch to a foot, so that each model is one twelfth the size of the actual road which it represents. ! Among the later methods of road I buildings which are pictured and de-I de-I scribed are the brick, concrete, asphalt- block, maeadem, sand-clay, gravel, and ! earth roads. Still other models show the processes of maintenance, resur-! resur-! facing, and bituminous macadam construction con-struction by the mixing and penetration penetra-tion methods. Recent additions to the j series illustrate road location and road-1 road-1 side treatment, drainage, strengthening strengthen-ing unstable foundations, etc. The history of ro. d construction, dealing with the early mitnods em ployed in Itily and France, is followed ! with discussions and illustrations of the I most modern ways of road building. . With the widely varing conditions in I the United Slates the scope of road . building is necessarily large, and in 1 many sections roads must be constructed construct-ed largely of the material at hand. The bulletin, Road Models,"is applicable to a wide range of conditions. In the section dealing with earth roads the subject ef the split-log drag is treated as follows: A suitable drag can be made from a log 7 or 8 inches in diameter and from 6 to 8 feet long. It should be carefully split and the halves ' with the flat sides vertical and facing to the front, connected by stakes. The halves, though of the same length, are : joined so that one end of the rear half . is from 16 to 20 inches nearer the cen-; cen-; ter of tne road than the corresponding i end of the front half. An ordinary j trace chain and a set of double trees I are then attached in such manner that j when the horses move forward the : drag will be pulled along the road at an ' angle of about 45 degrees, with the forward end nearest tne ditch in order to move the earth toward the road center. The drag should be light enough to be lifted by one man. The best material ma-terial is dry red cedar, though red elm ; and wslnut are excellent, while box I elder, soft maple elm, or willow are ! superior to oak, hickory, or ash. A platform is usually placed on the cross stakes to strengthen the drag and fur- ; nish a place for the diiver to stand. After a little practice a man can learn how best to shift his weight so as to make the drag cut, spread, and pack the earth properly. Filling the ruts by dragging up one side of the road and the other is all that should be undertaken the first time, but this should be repeated after each heavy rain. As a mile of road can be dragged in a few hours, this method of maintainance is simple and inexpensive. If the drag is used in conjunction with the road machine, fairly good earth roads can be built at a small expense. Dragging is done for 50 cents per mile in some parts of the country. At this rate a mile of earth road can be dragged once a month for $6 annually. Some remarkable remark-able results have accomplished with the drag without the aid of the road machine, ma-chine, j |