ROCKS OE THE NORTHERN HIGHLANDS. 



399 



bay the rock is covered by sand 

 for 120 yards, the only gap in 

 the entire section ; and this is 

 really filled in a little higher 

 up at the road-leveL This sand 

 must mask a slight fault and a 

 syncline ; for on its western 

 margin we come to higher beds 

 with an opposite dip. The first 

 of these is the base of the Do- 

 lomite, dipping easterly at 25°. 

 This rock is underlain at the 

 Pictish Tower by the Salter ella- 

 grit, with fossils, followed in 

 regular order by the Brown 

 Flags and Annelidian Quart- 

 zite, the basset edges of the 

 strata cropping out regularly 

 from E. to W. Then the Quart- 

 zite becomes horizontal, and 

 further on dips south-westerly, 

 and is overlain in normal se- 

 quence by the Brown Elags 

 (50-60 ft.), Salterella-gnt (15 

 ft.), and Dolomite. The last- 

 named is in full force, dipping 

 steadily to the S.W., its lower 

 (dark) and upper (white) mem- 

 bers being as completely ex- 

 posed as at Inchnadamff. AVest 

 of the Pictish Tower, the Assynt 

 series is thus seen to lie in a 

 broad low arch, and there can 

 be no question that the beds 

 are uninverted. 



Coming back to the east end 

 of this section, we observe a fact 

 which, for the sake of simplicity, 

 I omitted in my first description. 

 Resting on the Dolomite at 

 the little bay is quartzite un- 

 derlain by flags, dipping in the 

 same direction as the Dolo- 

 mite, but at a higher angle 

 (50°-60°), so that the edges of 

 the upper beds abut obliquely 

 onto the bed-surfaces of the 

 Dolomite. Vie ascertain by 

 further study that these over- 

 lying rocks belong to the over- 



