256 Through the Yang-tse Gorges 



960 miles from the sea, just 244 times that of tiij Tifames 

 at London. 



The comparison of the sediment, annually brought down 

 by the respective rivers at these two points, is as 2,000,000 

 cubic feet to 5,000,000,000, or as i to 2500. Taking the 

 drainage area of the Yang-tse at 600,000 square miles, and 

 estimating the sediment discharge as above, both Captain 

 Blakiston's and Dr. Guppy's figures give a rate of subaerial 

 denudation for the whole catchment basin, of about one 

 foot in 3000 years. Estimating four-fifths of this amount of 

 sediment as employed in raising the banks and filling up the 

 expanse of its inferior valley while inundated by the summer 

 floods, the remaining one-fifth is sufl5cient to create annually 

 a fresh island in the Pacific one mile square, and fifty 

 fathoms deep. The rapid rate at which the coast-line is 

 gaining on the ocean, startling ocular evidence of which is 

 presented to every old resident of Shanghai, is thus not 

 surprising. In the very near future the innumerable rocky 

 islands, which fringe the coast, and which now stand out of 

 the shallow muddy waters of the estuary, will look down 

 upon embanked paddy fields, precisely as the hills inland 

 from Shanghai now stand out from the fields, which have 

 been raised by the same process in recent geological times. 



It seems to me a matter of no doubt, that in quite recent 

 times the Yang-tse River, upon leaving the moimtains, 

 discharged its waters into the ocean through a series of 

 lakes, the remains of which still occupy a considerable 

 portion of the valley in winter, and which in summer are 

 enlarged by the floods to almost their original surface area. 

 The first of these lakes is comprised within the boundaries 

 of the present province of Hu-peh, and at the highest floods, 

 which occur every eighth or tenth year, making sport of 

 the numberless huge embankments, the whole country is 



