THE GROWTH OF THE YANGTZE DELTA 35 



. The silting up of the old channels, the Nan Ta Men or 

 South Great Channel, was between Kan Shan and the Che 

 Shan, the Pleh Tse Men or Middle Channel, was between 

 Che Shan and Ho Chuang Shan, and the North Channel 

 was north of Ho Chuang Shan, is probably due more to the 

 Yangtze silt rushing in on the flood tide and encountering 

 the ebb and fresh water discharge of the Chien Tang Kiang. 

 My recent investigations in the Hangchow Bay indicate 

 a very slow accretion as a total resultant of the many forces 

 at play. In many places erosion, in others accretion, but the 

 latter predominating. 



The Bore is the result of the delta-building in the Bay. 



Eesume 



I could add many other points — that I have gone into 

 — re the origin of the Whangpoo and the Tai-Hu, but space 

 dees not permit me to do so and most data I have are 

 already published in the reports mentioned. 



Ee viewing the various evidences, hydrological and 

 hydrographical, geological and historical, as well as the 

 actual processes of to-day, in regard to the growth of the 

 delta — I venture to say, and believing not to be far out — 

 that the delta below Chinkiang has been built up in the 

 last 10,000 years, or at most 20,000, and that the plain 

 form. At this rate, some 1,000-1,200 years from now the 

 Yangtze Cape will be at Gutzlaff and the familiar Island cliff 

 will then be a hill on the plain. The same length of time 

 will probably elapse before the Tsungming Island, or a new 

 island outside it, has enveloped Sha-Wei-Shan, the rock and 

 lighthouse which every northbound ship is now guided by. 



Prophency is a thankless task and probably 1,000 years 

 hence — if some members of the Eoyal Asiatic Society — which 

 I hope will then continue to exist — were to look up the 

 records of this lecture they may have cause to reflect upon 

 what foolish prognostications have here been attempted. 

 It is, however, interesting and useful to make an effort to 

 form some idea of what is going on around us. As Edkins 

 says "the same causes which have gradually produced this 

 great alluvial plain, on which Shanghai and all the other 

 cities on the plain were built, are still in operation gradually 

 forming fresh land to the seaward, filling up old channels 

 originating new ones, and by degrees increasing the eleva- 

 tion of the land." Without overflowing its banks and de- 



