READING BEDS. 



95 



new Survey was complete, and there has been opportunity of 

 examinino; it. 



In the Isle of Wight the Reading Beds consist almost entirely 

 of mottled clays, in which shades of red and purple predominate. 

 These rest on a slightly eroded surface of the Chalk, and contain at 

 their base small rolled flint pebbles. (See Fig. 16, from a sketch 

 by Sir Andrew Ramsay.) 



Fig. 16. 



Junction of the Chalk and Loiacr Tertiary Beds, in Alum Bay. 



The following section was measured, with the assistance of 

 Mr. Richard Gibbs, in 1852. 



Ft. In. 



Section of the Reading Beds in Alum Bay. 



Red and white mottled clay, with a ferruginous parting at 



4 feet - - - • - 

 Ferruginous-brown clayey sand - - - - 

 Bright-red and white mottled clay (pipeclay) 



Brown and grey sandy clay (with a bed towards the middle 

 of dark -red clay 3 feet thick) ; most sandy in the upper 



5 feet .-..--- 

 Tenacious, wet, red and white mottled clay 



Tenacious blue and brown ferruginous clay 



Brown sand covering an uneven eroded surface of Chalk 3 



As the strata are traced eastward their thickness increases to 

 110 feet at Downend, 92 feet at Ashey, 140 feet at Brading, and 

 163 feet at Whitecliff Bay. At the last-named locality they 

 consist principally of mottled clay, but are so hidden by landslips 

 and mud-streams that their details cannot at present be noted 

 and the total thickness here given is taken from the original 

 measurement made in 1852. 



The section in the railway cutting at Brading is now entirely 

 overgrown, but a sketch and description, made by Mr. Whitaker 

 during the construction of the line in 1878, is here given. 

 (Fig. 17.) 



