266 M. DE Bonnard's Notices 



gical description of the Hartz,* has not only expressed the 

 same opinion, but it appears from what Messrs Lame and 

 Clapeyron state, still preserves it, after subsequent observa- 

 tions undertaken for the sake of verifying it. Supported by 

 this new and imposing sanction, this opinion would appear 

 to merit entire confidence. Yet a very different opinion 

 has for many years been propagated among German geolo- 

 gists, and it appears to me interesting to make it known. 

 It has been very concisely exposed by M. de Raumer in 

 1811, in his Fragmens geugnostiques ; M. Schulze has 

 adopted it in his memoir on the Hartz, inserted in the jin- 

 nuaire minerahgique of M. Leonhard for 1815 ; since that 

 time this opinion has been defended and opposed in many 

 German works with which I am unacquainted.t I shall^ 

 consequently, in the following notices, principally rest on 

 my own obserrations, by which I was, in 1806, led to con- 

 ceive an analogous opinion ; but I shall confine myself to 

 the exposition of doubts ; the extreme reserve we should 

 always impose on ourselves when we wish to draw any con- 

 clusion from geological observations, is imperiously demand- 

 ed, when this conclusion is opposed to an opinion supported 

 by M. Hausmann. 



It is more particularly when studying the western part of 

 the Hartz, that we may be led to doubt the primordial na- 

 ture of the granite of the Brocken. It should in the first 

 place be remarked that throughout the Hartz, and especi- 

 ally throughout the greywacke formation, which constitutes 

 at least three-fourths of the mass of the mountains, the beds 

 are observed to have a general direction towards the E.N.E. 

 and a general dip towards the S.S.E. with but a few local 

 exceptions. It has been seen, in the preceding notice, 

 that the Hartz mountains are elongated from north-west 



* Geognostiche Skizze von Siid-Nieder-Sachsen, inserted in the 2d No. 

 of the Nord-Deutsche Beytrage zur Berg und HiittenkuDde. Brunswick, 

 1807. 



+ In a very interesting memoir, inserted in the Annuaire mineralo- 

 gique of M. Lreonhard, 1821, and w^hich only reached me after these 

 notices were written, M. Germar opposes the idea of the comparatively 

 modern nature of the Hartz granite, which he considers as of primordial 

 formation. 



