National Geographic : 1923 Apr
FIVE MODERN MEANS OF AMERICAN TRANSPORTATION The rivers of the country carry a considerable tonnage; coal moves down the Ohio and the Mississippi from Pittsburgh toNew Orleans at a fraction of the rail cost. The electric lines of the country, urban and iriterurban, carry some ten billion passengers annually. Over the improved highways of the United States, motor cars cover billions of miles. The canals were our first important freight arteries, and astraffic problems increase are expected to come into their own again. The railways, as the years come and go, will probably beforced torelinquish low-class freight to the canals and find themselves kept busy handling high-class commodities.