By October, 1832, seven coaches, belonging to various proprietors, were doing fifty journeys a week between different places on the line; so that thus far the original idea of Parliament, in enforcing against railways the principle of a common user of their lines by the public, had appeared to be warranted. A year later, however, the railway company, finding, as Jeans tells us, that it would be more convenient and more advantageous for them to take the whole carrying trade in their own hands and supersede the horses by steam locomotives, bought out, on what were considered generous terms, {228}the interests of the four coach proprietors then carrying passengers on their own account on the lines. Actual experience had thus nullified the expectation that a railway would be simply a rail-road upon which anyone would be able to run his own conveyances as on an ordinary turnpike road. From October, 1833, the whole of the passenger traffic (then undergoing rapid expansion) was conducted by the company. In April, 1834, the directors, who had by this time acquired some other and better engines, announced that they had commenced to run, six times a day, both "coaches" (for passengers) and "carriages" (for goods) by locomotives; and this date, probably, marks the final disappearance of the horse as a means of traction for passenger traffic on public railways in England, though the word "coaches," introduced into the railway vocabulary under the circumstances here narrated, has remained in use ever since among railway men as applied to rolling stock for passenger traffic. Unlike its predecessors in Surrey, and though facing various difficulties at the outset, the Stockton and Darlington line attained to a considerable degree of prosperity. After undergoing various extensions from time to time, and playing a leading part in the industrial expansion of the district it served, it was incorporated into what is now the North-Eastern Railway system. Summing up the respects in which the Stockton and Darlington line had carried forward the story of railway development, we find that it (1) established the practicability of substituting locomotive for horse traction on railways; (2) introduced the provision of waggons by the railway company, instead of leaving these to be found by carriers and traders; (3) proved that railways were as well adapted to the transport of passengers as they were to the carriage of goods; (4) showed by actual experience that the idea of a common user of railways was impracticable; and (5) prepared the way for the eventual recognition, even by Parliament itself, of the principle that transport on a line of railway operated by locomotives must, in the nature of things, be the monopoly of the owning and responsible railway company.