We have here the first suggestion of any approach to a real system of inland communication, as applying to the country in general, which had been attempted since the Romans made the last of their great roads in Britain. Apart from the natural limitations of navigable rivers, the turnpike roads so far constructed had been chiefly designed to serve local interests, and successive rulers or Governments had either failed to realise the importance of carrying out a well-planned scheme of inland communication, embracing a great part even if not the whole of the country, or had been lacking in the energy, or the means, to supply what had become one of the greatest of national wants.
There was thus all the more credit due to the little group of far-sighted, enterprising and patriotic individuals whose names I have mentioned that they should themselves have undertaken work which was to have an important influence on the industrial and social conditions of the country. Yet the nature of the conditions under which the Trent and the Mersey section of the Grand Trunk system was made afforded an early example of the physical difficulties attendant on canal construction in England which were to be a leading cause of the decline of canals as soon as the greater advantages of the railway and the locomotive had been established.
Canals were superior to rivers in so far as they could be taken where rivers did not go, and could be kept under control in regard to water supply without the drawbacks of floods or droughts, of high tides, or of being silted up by sand or mud. It is, indeed, reported that when, after he had made a strong pronouncement in favour of canals, James Brindley was asked by a Parliamentary Committee, { 174}"Then what do you think rivers are for?" he replied, "To supply canals with water."
On the other hand, water would not flow up-hill in canals any more than in rivers, and in the making and operation of canals there was, literally as well as figuratively, a great deal of up-hill work to do.
Between the Mersey and the Trent there were considerable elevations which formed very difficult country for water transport. These elevations had to be overcome by the gradual rising of the canal, by means of locks, to a certain height, by the construction, at that point, of a tunnel through the hills, and by a fresh series of locks on the other side, to allow of a lower level being reached again. The rise of the Trent and Mersey Canal from the Mersey to the summit at Harecastle, near the Staffordshire Potteries, was 395 ft., a final climb of 316 ft. being made by means of a flight of thirty-five locks. Through Harecastle Hill there was driven a tunnel a mile and two-thirds in length, with a height of 12 ft. and a breadth of 9 ft. 4 in.[25] South of this tunnel the canal descended to the level of the Trent, a fall of 288 ft., by means of forty locks. In addition to this the canal, in its course of 90 miles, had to pass through four other tunnels and be carried across the river Dove by an aqueduct of twenty-three arches and at four points over windings of the Trent, which it followed to its junction therewith at Wilden Ferry.