The application of the double and the triple expansion principle has been quite as successful with locomotive as with marine engines in saving fuel and gaining power--that is, it has decreased the cost per ton-mile of hauling freight and likewise the cost of transporting passengers. Enlarged "fire-boxes," or furnaces,[15] enable steam to be made more rapidly and to give higher speed.[16] Only a few years ago forty-eight hours was the scheduled time between New York and Chicago; now there are about forty trains a day between these two cities, several of which make the trip in twenty-four hours or less. =Railway Development.=--The railway as a common carrier, having its right by virtue of a government charter, dates from 1801, when a tramway was built between Croydon and Wandsworth, two suburbs of London. The rails were iron straps, nailed to wooden stringers. The charter was carefully drawn in order to prevent the road from competing with omnibus lines and public cabs. When the steam locomotive succeeded horse-power, however, there followed an era of railway development that in a few years revolutionized the carrying trade in the thickly settled parts of the United States and Europe. Short, independent lines were constructed without any reference whatever to the natural movement of traffic. There seemed but one idea, namely, to connect two cities or towns. Indeed, the absence of a definite plan was much similar to that of the interurban electric roads a century later; local traffic was the only consideration. At first an opinion prevailed that the road-bed of the railway ought to be a public highway upon which any individual or company might run its own conveyances, on the payment of a fixed toll; indeed, in both Europe and the United States, public opinion could see no difference between the railway and the canal. The employment of a steam-driven locomotive engine, however, made such a plan impossible, and demonstrated that the roads must be thoroughly organized. At the close of 1850 there were nearly four hundred different railway companies in England; in the United States about a dozen companies were required to make the connection of New York City and Buffalo. A few of these paid dividends; a large majority barely met their operating expenses, defaulting the interest on their bonds; a great many were hopelessly bankrupt. =Consolidation of Connecting Lines.=--Between 1850 and 1865 a new feature entered into railway management, namely, the union of connecting lines. This was a positive advantage, for the operating expenses of the sixteen lines, now a part of the New York Central, between New York and Buffalo were scarcely greater than the expenses of one-third that number. The service was much quicker, better, and cheaper. In England the several hundred companies were reduced to twelve; in France the thirty-five or more companies were reduced to six in number.