Explanation of the plates. 
Is 
Introductory Notice, and Description of the Geological 
Phenomena illustrated hy Plate L 
Plate 1, 
an imaginary Section constructed to express, by the in- 
sertion of names, and colours, the relative positions of the 
®iost important classes, both of unstratified and stratified 
^■ocks, as far as they have yet been ascertained. It is 
founded on many series of accurate observations, on several 
foes taken across Europe, between the British islands and 
e Mediterranean Sea. Although no single straight line 
ibits every formation complete in the full order of 
'recession here represented, no fact is inserted for which 
th' cannot be found. The near approximation of 
® synoptic representation to the facts exhibited bv an 
1 c* 1 • . 
the niay be estimated by comparing it with 
Qon section across Europe, published by Mr. 
Ass ^ Report of the Proceedings of the British 
for the Advancement of Science, 1832, and 
IS sections of England, in Phillips and Conybeare’s 
of England and Wales. 
iji , ^ *^I>ief merit of the above Section is due to the 
^r. Thomas Webster; it is founded on a more 
p e section which has for several years been used by 
the which exhibits the relations of 
ranitic and Volcanic rocks to the stratified formations, 
u. ' 
