on the Harlz. 265 



quartz rocks, and the hard slates without fossils as imme- 

 diately following the granite in the order of antiquity and as 

 belonging with it to the primitive formations ; lastly we 

 suppose that the greywackes, the micaceous argillaceous 

 slates and the limestones, whose place is generally well de- 

 termined among the transition rocks, must rest on the other 

 rocks. 



Such in fact is the opinion long since adopted with respect 

 to the rocks of the Hartz, and independently of general 

 analogies which may lead us to conceive it, local observation 

 affords a sufficient number of facts for its support. Quitting 

 the Brocken, and proceeding towards the N. or N.E., that 

 is in the space comprised between this mountain and the 

 towns of Neustadt, Ilsenburg, and Wernigerode, we scarcely 

 find any thing, besides the granite, but these crystalline and 

 hard rocks which are regarded as primitive; and in many 

 places we may conclude froni their disposition that they 

 immediately rest on the central granite. Proceeding south- 

 ward from the Brocken, analogous rocks are met with in 

 the environs of Andreasberg, with schists and flinty slates 

 which do not contain a trace of organic remains, and they 

 are sometimes seen to rest on granite ; a similar superposition 

 may elsewhere be concluded from the dip of the schistose 

 beds. Proceeding still further south, we observe that the 

 reputed primitive rocks are evidently covered by greywacke. 

 Lastly, throughout the whole eastern parts of the Hartz, we 

 remark a general dip of the greywacke beds to the S.E., 

 leading us to consider it as resting on the granite of the 

 Brocken, or on the other rocks previously observed. 



The mineralogists who have inhabited, or until lately 

 visited the Hartz, have conceived ideas slightly diflerent from 

 each other with respect to the antiquity of the horn/els^ 

 the quartz rock, and the hard schist of the environs of An- 

 dreasberg ; but they are all agreed in recognising the pri-, 

 mordial nature of the granite, and its anteriority with respect 

 to all the other rocks, which they regard as above it. M. 

 Hausmann, who in 1807 published a very instructive geolo- 



