Railroads 179 cross. The people there are as civilized as those in Massachusetts, Illinois, and New York, but they are so few in number that it does not pay to build railroads to carry their scanty freight. How plains and mountains influence the number of railroads. On a relief map of California notice how largely the railroads are lim- ited to the low, level regions of the coast and the great central valley or plain. In the first place, the mountains have too sparse a popula- tion to provide much railroad business, while the plain is thickly settled and productive. Second, railroads are extremely expensive among mountains. The grades, curves, bridges, cuttings, and tunnels make it cost ten, twenty, or even fifty times as much to build a mile of rail- road in the mountains as in the plains. Moreover, the mountain railroad is relatively long because of the windings, and the expense of running trains is great not only because much coal is needed, but be- cause of wear and tear, and low speed. How natural resources attract railroads. Among the mountain railroads of the world a large number have been built to open up nat- ural resources, such as minerals. For example, the Leadville road in Colorado is famous as the highest in the United States. The rail- road would scarcely have been built if it had not been for the silver and lead ores that attracted large numbers of miners. Elsewhere mountain railroads have often been built to tap resources of lumber in rugged regions that would otherwise have no good lines of communica- tion. The woods of northern Maine contain many such roads. Another resource of rugged regions is the scenery. Many people will pay more than the ordinary rate of fare in order to enjoy it; 0D. Dickie F1g. 130. Nine pairs of horses are hauling four wagon loads of wool to market, across the Wyo- ming sage-brush. Which would be the better substitute — a railroad train or a motor truck?