402 M. Keilhau's Theory of Granite and other RocTiS. 



altogether independent of the previous appearance of the granitic 

 formations at these places (for it is only the granite, as already re- 

 marked, that we have here to take into our consideration). Still 

 we will not pass over any fact which tends to strengthen a re- 

 sult so rich in consequences. Although the stratified districts 

 are comparatively much less considerable in extent than the 

 granitic, and remarkably so in regard to their narrowness, yet 

 the most of them extend more than twenty-eight square miles 

 (four square Norwegian miles), which perhaps with some, may 

 lessen the weight of what has been adduced. It must then be re- 

 marked, that much smaller portions, either partially or entirely 

 separated from the originally connected tracts of clayslate and 

 limestone, always exhibit the same direction and dip which 

 exist in the whole. The granite masses present deep sinuosi- 

 ties, into which long tongue-formed portions of the slate enter, 

 or the same peninsula-like separation takes place by means of 

 large offsets from the granite which enclose portions of slate 

 between them ; in either case, there is no disturbance to be 

 traced in the general arrangement ; finally, we have examples 

 of complete separations, where also no change presents itself in 

 the disjoined portions. This last circumstance is the most 

 striking of the whole. In the middle of the great granite dis- 

 trict to the north of Christiania, lies one of these entirely iso- 

 lated portions of slate and limestone, which has a diameter of 

 about one mile (one-fourth of a Norwegian mile). Here there 

 is no clayslate, but in place of it only siliceous slate ; and in- 

 stead of limestone, there is a light coloured granular marble. 

 Notwithstanding the whole strata have undergone the ordinary 

 chemical alterations from their proximity to the granite, their 

 position is perfectly undisturbed, inasmuch as they exhibit the 

 usual dip and direction. Next, after this greatest specimen of 

 completely separated stratified masses, I have seen smaller and 

 smaller portions, down to pieces as small as the imbedded frag- 

 ments of a conglomerate ; and in all these this striking pa- 

 rallelism of the strata is recognisable.* Some of the observa- 



" Do not the sandstone masses enclosed in the basalt of the Blaiie Kuppe 

 at Eschwege exhibit the same relation ? I infer this from a remark by 

 Zeuschner, in Leonhard's " Neues Jahrbuch," 1836, p. 648. The portions 

 of greywacke occurring in the Hartz granite, and the fragments of stratified 



