The important result of the growth and improvement of railways was the great reduction in the cost of transportation. At the close of the period before the war it had been demonstrated that railroads could economically carry high grade freight such as flour, live stock, lighter manufactured goods and general merchandise, but as yet they had been unable to compete successfully with waterways for the transportation of grain, and the carriage for long distances of such low-grade freight as coal and ore had not been attempted. As the railway developed, however, its use was extended, and it was soon found that there was no commodity so cheap that it could not be profitably handled. Accompanying the extension of the service to include all kinds of bulky freight there was an uninterrupted decline in the general level of rates on all classes of goods, resulting from the increased efficiency of roads, the stress of competition, and above all from the tremendous increase of traffic. The rate per ton per mile decreased from 1.92 cents in 1867 to 0.73 of a cent in 1900. This reduction of transportation charges was one of the most potent factors determining the course of economic progress. Field, mine, forest and store were linked together into a unified whole; raw materials could be concentrated at any point and there was practically no limit to the extent of the market for finished commodities. The increase of the tonnage of railway freight from less than 20,000,000 tons in 1860 to almost 600,000,000 tons in 1900 is the best index of the growth of internal trade during this period. As the railways increased in importance, transportation on most of the inland waterways declined. Nearly 1,700 miles of canals were abandoned between 1860 and 1900. After 1880 there was a gradual decrease of nearly all canal and river traffic. The Great Lakes were practically the only inland waterway that retained an important position in internal trade. The unusually favorable conditions prevailing for the growth of traffic on these bodies of water enabled their commerce to thrive and expand at a rate which compared favorably at all times with the growth of railway traffic.