1863.] MACKENZIE BITUMINOUS MINERAL. 523 



of the mineral were discovered, from which the specimens in the 

 Society's possession were taken. 



Where the cutting commences, ahout 1| mile from Dingwall, 

 the rock consists of a grey sandstone similar to that of the Tulloch 

 Quarry, and having a north-west dip ; but the strata are much 

 disturbed and broken. The beds continue for about 18 yards, at 

 the end of which space there appears a shaly rock mixed with clay, 

 dipping north at a sharp angle, and underlying the sandstone for 

 about 12 yards. 



Where the shale disappears below the cutting, the. sandstone recurs 

 for about 20 yards, also dipping north ; and it was here that the 

 first vein of the mineral appeared, running S.E. to N.W. through 

 the bed of sandstone. For these 20 yards the rock is much broken 

 and arched, in rather thin beds, bending from south to north ; after 

 which the shaly rock reascends, alternating with the grey sandstone, 

 and with occasional clay-seams between the beds of shale and sand- 

 stone, between which the mineral is again found in veins varying 

 in thickness from \ inch to \\ inch. The arched strata of shale 

 and sandstone somewhat resemble the fig. 21, p. 199, of Dr. Daw- 

 son's i Acadian Geology.' Occasionally the clay rests behind the 

 mineral, and between the shale- and sandstone-strata. 



Similar rocks continue for 60 yards, during the whole of which 

 portion of the cutting they are much disturbed and contorted, and 

 the mineral lies in thin veins. The dip of the rocks is here still 

 N.W., and the veins of the mineral run through them W. by N. The 

 sandstone appears by itself for about 8 yards, and then the shaly 

 rock. Here the mineral has been found in greater quantities and 

 thickness, running in veins of 1, 2, and 3 inches, and adhering 

 very firmly to, and intimately blended with, the exterior face of the 

 sandstone. It also outcrops at the surface of the sandstone-rock 

 under the clay which covers the surface of the hillside. The mi- 

 neral found adhering to the sandstone is very fine and pure, and 

 superior in quality to that found in the shale and clay. 



Shaly rock continues after this for 6 yards, dipping S.W. to N.E. ; 

 after which the uplifted sandstone appears for 20 yards, in much 

 thicker beds and less broken than the previous rock, and dipping S. ; 

 but no mineral appears. The shaly rock then reappears for 22 

 yards, also dipping S. ; but about 5 feet behind the face of the 

 railway-cutting the sandstone shows itself, overlapping the shale ; 

 and at the junction a thin vein of inferior mineral, about \ inch thick, 

 lies like packing between the two strata. Conglomerate next ap- 

 pears upon the top of the sandstone, and the vein of mineral goes 

 quite through it. 



From where the sandstone overlaps the shaly rock, the conglo- 

 merate appears alone for about a quarter of a mile, at the end of 

 which distance the cutting is continued through clay. 



The conglomerate strikes east and west, and has a slight dip to the 

 north, whilst the veins of the mineral, which are very numerous, 

 varying from \ inch to 3 inches in thickness, traverse the conglo- 

 merate at an angle of almost 45° in the direction S.E. to N.W. 



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