14 



DESCRIPTION of the 



breadth of this bed of whin is thirteen feet ; and where it fplits, 

 its three branches are, fix, four, and three feet in diameter. The 

 trend or ftretch of this bed is from weft to eaft ; but upon the 

 weft fide of the river, it curves fomewhat to the fouth-weft. Its 

 compofition is nearly the fame with the three other beds of whin 

 which I have before mentioned. It is of a brownifh-black co- 

 lour, and, when placed in certain directions, it fhows fpecks of 

 luftre. It is vertical in its pofition, has a great degree of indu- 

 ration, and its general fracture is roughly conchoidal. 



Soil. : 



Aggregate 

 rock. 





Blue 

 Clay flate. 



The river. 



Upon palling this bed of whin, the river ceafes to be deeply 

 imbedded in the rocks ; but the aggregate rock and the clay flate 

 ftill continue to be feen for a fliort diftance, in a fhelvy acclivi- 

 ty, where they are loft to view in a long narrow plain, deeply 

 covered with a bed of gravel, compofed of the debris of the in- 

 terior mountains. The river here flows over this bed of gra- 

 vel for a confiderable fpace ; and upon this narrow flat, we pafs 

 through between two of the mod elevated points in the fouth la- 

 teral range of this part of the Grampians. Although the obtru- 

 fion of this mafs of gravel cuts off from infpect-ion the continui- 

 ty of the laft- mentioned rocks, yet the broken and abrupt fides 

 of the mountains, clofe upon each hand, clearly points out, that 

 this part of the fouth lateral range is entirely compofed of mica- 

 ceous fhiftus. Here, we are deprived of the junction of the mi- 

 caceous lhiftus with the two former rocks ; and the lofs of all 



fuch 



