DESCRIPTION OF THE PLATES. 



Plate 7. Fig. 7. Section of the Goon Laz and the Pink Mine, p. 137. 



8. Section of Tin Croft Mine, p. 132. 



Plate 8. Fig. 9. Grotind Plan of Herland and Drannack and Princf 

 George Copper Mines, p. 146. 



> 10, Section of Pleasure, Fancy, and North Ilerland Vein*?, 



p. 149. 

 11. Section of Manor Old Vein, p. 151. 



PLATES 9, 10, 10,* 11. 



In illustration of Mr. Webster's paper on the Strata Iving over the Chalk, p. ili 1 . 



Plate 9. Map of the Basin of the Isle of Wight, shewing the hollow occa- 

 sioned bj a depression in the chalk within which some of the more 

 recent strata appear to have been deposited ; and also a part of the 

 district in which the chalk is found wanting, where the strata 

 below the chalk are exposed, p. I6S and 170. The detached 

 figure below repi'esents on a larger scale the west end of the Isle 

 of Wight, where the Section of PI. 1 1 is taken. 



Plate 10. Map of a similar Basin in the vicinity of London, p. 171, 172. 



Plate 10.*Map, shewing the relative position of the Basins of Paris, London, 

 and the Isle of Wight. 



Plate 11. Section of the Isle of Wight, from north to south, shewing the 

 middle range of hills, consisting of strata of chalk, very highly 

 inclined ; the horizontal strata inferior to the chalk on the south, 

 (right side of the plate) ; and the vertical strata of Alum Bay to 

 the north, of later date than the chalk. Against the latter the 

 horizontal and alternating series of marine antl freshwater strata 

 in Ileaden Hill, come up almost abruptly. The coloured section 

 represents Alum Bay and Ileaden Hill on a larger scale. — p. 182. 

 ct. seq. 



PLATES 12, 13. 



In illustration of Dr. Mac Culloch's paper on the Junction of Trap and Sand- 

 stone at Stirling Castle, p. 305. 



Plate 12. Gives a general view of the Rock where the junction takes place, 

 Plate 13. Is a more detailed representation of that part of the junction 



where the strata of sandstone are dislocated and broken. It 



exhibits also the diftcreut colours of the trap and sandstone. 



The white line, near the fragment, is a vein of calcareous spar, 



p. 30G. 



