For a great part of its route the Grand Canal runs through a level and marshy district. In some places, indeed, the canal becomes merged in the lakes and swamps which surround it. In other places, however, where there appears to be a special risk of inundation, the banks of the canal are well faced with stone. The canal, before leaving the lakes in the southern part of Shanting, used to run nearly parallel with that stream for more than a hundred miles, and between it and the New Salt River for a great part of that distance. This river, formerly described as one well adapted for navigation, has now become completely silted up, and at Kiafung the difference of level is so trifling that the siltage there has been enough to turn the current into the river Wei and elsewhere. At the opening of the canal there is a sluice nearly 100 yards across, through which the water is said to rush into the river like a mill-race. There is, however, a makeshift sort of appearance about the canal works generally. The banks are in many places constructed of earth, strengthened with sorghum stalks and strongly bound with cordage; and Davis, in speaking of the attempt made to repair the damage caused by the inundation of the Yellow River in this way, remarks very justly that if the science of a Brunel[133] could be allowed to operate on the Yellow River and Grand Canal, “a benefit might be conferred on the Chinese that would more than compensate for all the evil we have inflicted with our opium and our guns.”
At about 70 miles from its mouth the Grand Canal reaches the Yellow River, and between the Yellow and Yantsz’ rivers, a distance of 90 miles, it is carried largely upon a raised work of earth, kept together by retaining walls of stone, which are in some places not less than 20 feet above the surrounding country. The width of the channel at this point is about 200 feet, and the current is stated to be three miles an hour. South of the Hwang-ho there are several large towns below the level of these walls, which would be overwhelmed with destruction if they were to give way. From these towns—the principal being Hwai-ngang and Pauying—the canal falls to the Yantsz’, and at Yangchan its level is again below that of the houses on either side. Every stream or lake whose waters can be led into it has a connection with the canal, which has several inlets into the great river Yantsz’, whence navigation is possible for a distance of 2900 miles. East of Chin Kiang the canal leaves the Yantsz’, and proceeds through a rich and fertile country, highly cultivated, and supporting an enormous population, Suchan and Hangchan being among the principal towns on its banks.