92 GEOLOGY OF THE ISLE OF WIGHT 



through his embankment. The harbour was finally 

 reclaimed at great cost in 1880, the present embankment 

 enclosing an area of 600 acres. 



The history of the Western Yar is similar to that of the 

 Eastern. The main stream must have flowed from land 

 now destroyed by the sea stretching far south of Fresh- 

 water Gate. All that is left is its tidal estuary, and the 

 gravel terraces and alluvial flat formed in the last part of 

 its course. Of a tributary stream an interesting relic 

 remains. For more than 2 miles from Chilton Chine 

 through Brook to Compton Grange a bed of river gravel 

 lies at the top of the cliff, marking the course of an old 

 stream, of which coast erosion has made a longitudinal 

 section. This was a tributary of the Yar, when the 

 mammoth left his remains in the gravel at Grange Chine 

 and Freshwater Gate. Down the centre of the gravels 

 lies a strip of alluvium laid down by a stream following 

 the same course in later days. The sea had probably by 

 this time cut into the stream ; and it most likely flowed 

 into the sea somewhere west of Brook. In the alluvium 

 hazel nuts and twigs of trees are found at Shippard's 

 Chine near Brook. 



The lower course of the Medina is a submerged river 

 valley, the tide flowing up to Newport. The river rises 

 near Chale, and flows through a strip of alluvium, over- 

 grown with marsh vegetation, known as " The Wilder- 

 ness." This upper course of the Medina, from the absence 

 of gravels or brick earth, has the appearance of a com- 

 paratively modern river. But the Medina has a further 

 history. If you look at the map you will see branches 

 of the Yar running south to north as transverse streams, 

 but the main course is that of a lateral river. Look at 

 the two chief sources of the Yar the stream from near 

 Whitwell and Niton, and that from the Wroxall valley. 

 When they get down to the marshes near Rookley and 

 Merston, they are not flowing at all in the direction of 



