Ch. XX.] 



SILTING UP OF ESTUARIES. 



517 



By the exclusion of the sea, thousands of acres in the in- 

 terior have become cultivated lands ; and, exclusive of smaller 

 pools, upwards of sixty freshwater lakes have been formed, 

 varying in depth from fifteen to thirty feet, and in extent 



from one acre to twelve hundred."* 



Yare, and other 



rivers, frequently communicate with these sheets of water ; 

 and thus they are liable to be filled up gradually with lacus- 

 trine and fluviatile deposits, and to be converted into land 

 covered with forests. Yet it must not be imagined, that the 

 acquisition of new land fit for cultivation in Norfolk and 

 Suffolk indicates any permanent growth of the eastern limits 

 of our island to compensate its reiterated losses. No delta 

 can form on such a shore. 



Immediately off Yarmouth, and parallel to the shore, is a 

 ^reat range of sand-banks, the shape of which varies slowly 

 from year to year, and often suddenly after great storms. 

 Captain Hewitt, E.N., found in these banks, in 1836, a broad 

 channel sixty-five feet deep, where there was only a depth of 

 four feet during a prior survey in 1822. The sea had exca- 

 vated to the depth of sixty feet in the course of fourteen years, 

 or perhaps a shorter period. The new channel thus formed 



Yarmouth 



m 



set of the waves and currents might endanger the submer- 

 gence of the land gained within the ancient estuary of the 



Yare. 



thrown 



estuaries on our eastern coast, where there is not a large body 



maintain 



mind that the marine 



materials 



o — o 7 CJ 



cliffs, and ready to form a bar anywhere the instant its course 

 is interrupted or checked by any opposing st 



earn 



The 



Yare 



miles 



manner 



remote 



the sea at Aldborough, until its ancient outlet was barred up 



\ 



* Taylor's Geology of East Norfolk, p. 10. 



