162 SPARKS FROM A GEOLOGIST'S HAMMER. 



equal to all the New England and Middle States of our 

 Union. 



Since tbe time of Yu, the Hoang Ho has made exten- 

 sive changes in its bed not less than eight times previously 

 to the last change. The great delta has been cut in every 

 direction. Sometimes the exclusive outlet of the river 

 has been by one or more mouths in the Gulf of Pe-chili; 

 at others it has been exclusively in the Yellow Sea; and 

 at still others the river has had outlets in both directions. 

 The Yang-tse has participated to some extent in these 

 wanderings. In the meantime the Yellow Sea and the 

 Gulf of Pe-chili have been filling up with sediments. In 

 many places the shore-line has traveled one hundred feet 

 per year for the last two thousand years. In other places 

 the change is not over thirty feet per year. A recent 

 writer calculates that the sediments of the three great 

 rivers of China would fill the Yellow Sea and the Gulfs 

 of Pe-chili and Lian Tung in 24,000 years.* 



The increase of land is probably in part due to a slow 

 rising of the eastern border of the continent. Such a ris- 

 ing is felt at numerous places. The island of Tsung-Ming 

 at the mouth of the Yang-tse, which now has a population 

 of half a million, did not exist in the fourteenth century. 

 Beaches of recent shells are seen in the south of China, 

 many feet above the present sea-level. Similar beaches 

 are found on the Japanese -islands from fifty to one thou- 

 sand feet above the sea. On the island of Formosa, such 

 beaches occur at an elevation of 1,100 feet. A Dutch fort, 

 built in 1634, upon an island detached from Formosa, is 

 now some distance inland, and stands in the center of a 

 large city. 



*H. B. Guppy, Nature, xxii, 448. Mr. A. Woeikoff thinks this period should 

 be extended to 28,000 years. (Nature, xxiii, 9.) 



