EXPLANATION OF THE PLATES.
Introductory Notice, and Description o f the Geological
Phenomena illustrated by Plate I.
P late 1,
Is an imaginary Section constructed to express, by the insertion
of names, and colours, the relative positions of the
most important classes, both of unstratified and stratified
rocks, as far as they have yet been ascertained. It is
founded on many series of accurate observations, on several
lines taken across Europe, between the British islands and
the Mediterranean Sea. Although no single straight line
exhibits every formation complete in the full order of
succession here represented, no fact is inserted for which
authority cannot be found. The near approximation of
this synoptic representation to the facts exhibited by an
actual section, may be estimated by comparing it with
the admirable section across Europe, published by Mr.
Conybeare in the Report of the Proceedings of the British
Association for the Advancement of Science, 1832, and
with his sections of England, in Phillips and Conybeare’s
Geology of England and Wales.
The chief merit of the above Section is due to the
Talents of Mr. Thomas Webster; it is founded on a more
simple section which has for several years been used by
him in his lectures, and which exhibits the relations of
the Granitic and Volcanic rocks to the stratified formations,
G. II . B