266 Professor Sedgwick and Mr. Murchison on the 



many such, as they recur perpetually. We will, however, illustrate by a woodcut 

 one more example of contortion and fracture, taken from the banks of the Moselle 

 opposite Braideburg. Beds of arenaceous and slaty grauwacke alternate, and are 

 violently contorted ; and in one part of a lofty cliff they are broken off and co- 

 vered transversely by another series of slaty beds of the same age (see woodcut, 

 fig. 9.). 



Fig. 9. 



Dislocation on the banks of the Moselle opposite Braideburg. 



Dip N.W. 



The dislocations, such as are here noticed, and still more the contortions on a vast 

 scale, which have inverted whole tracts of country, would have thrown such diffi- 

 culties in our way, that we could not have attempted to place, even in an approxi- 

 mate order, the formations above described, had not the less disturbed sections in 

 a part of Westphalia given us the master-key to the true succession of the sedi- 

 mentary Palaeozoic rocks of these provinces. 



In traversing the Rhenish tracts, we repeatedly noticed the overlying ter- 

 tiary deposits of sand, conglomerate, and brown coal, often associated (as in the 

 Westerwald around Rennerod, &c.) with great tabular eruptive masses of ba- 

 salt ; but it is not our object to treat of these deposits, and they have been 

 elaborately described by Professor Noggerath and other German authors. Our 

 own countryman, Mr. Horner*, has given us some new views concerning both their 

 contents and their relations to the interpolated igneous rocks near Bonn. It is 

 enough for our present purpose simply to state, that between these recent tertiary 

 formations and the Palaeozoic rocks, all connecting links, in the form of interme- 

 diate secondary strata, are entirely wanting in the mountainous provinces of this 

 part of Germany. 



* Geol. Trans., 2nd Series, vol. iv. p. 433 et seq. 



