"The Swansea Canal belongs to the Great Western Railway Company. It is a narrow canal, 16½ miles in length, and has 36 locks. The traffic has diminished ... for reasons similar to those given with respect to the Glamorganshire Canal." Much more, however, than the provision of locks was necessitated by the physical conditions of a country naturally unsuited for artificial waterways. In some instances the canals were taken across broad valleys by means of viaducts designed to allow of the waterway being maintained at the same {305}level; and certain of the works thus carried out were, in their day, deservedly regarded as of considerable engineering importance. The Chirk aqueduct, which carries the Ellesmere Canal across a 700-feet stretch in the Ceriog valley, and at a height of 70 feet above the level of the river, and the Pontcysyllte aqueduct, 1007 feet long, which takes the same canal over the river Dee, are spoken of by Phillips, in his "General History of Inland Navigation" (1803), as "among the boldest efforts of human invention in modern times." Elsewhere the canals had to pass along high embankments or through deep cuttings. Canal tunnels of up to three miles in length were not infrequent, though some of these were made so narrow--in the interests of economy--that they had no towing-path, the boats being taken through by men who lay on their backs on the cargo, and pushed against the sides of the tunnel with their feet. Alternatively, it was sometimes possible to avoid rising ground or deep valleys, necessitating locks, by making wide detours in preference to taking the shortest route, as a railway would do. Thus the distance by canal between Liverpool and Wigan is thirty-four miles, as compared with a distance of only nineteen by rail. From Liverpool to Leeds is 128 miles by canal and eighty by rail. These windings made the canal compare still more unfavourably with the railway when it was considered that the speed of transport on the former was only about two and a half miles an hour, without counting delays at the locks; and of these there are, between Liverpool and Leeds, no fewer than ninety-three. But just because these engineering works had been so bold and so costly, or left so much to be desired in regard to length of route, and just because so many physical difficulties had had to be overcome, it may well have happened that when what was universally considered a better means of transport was presented, general doubts arose as to the wisdom and practicability of reconstructing, in effect, the whole canal system to enable it to compete better with the railways in catering for that through traffic for which the canals themselves were so ill adapted.