EXCURSION VI. 



131 



German Ocean. This position had been acquired before the 

 Arran granite was injected amid the strata of slate, and ere 

 yet any of the sandstone beds which succeed it had been 

 deposited. These sandstones (old red and carboniferous) are 

 conformable to one another, and the deposits blend at both 

 sides of the section, Achab farm and the Fallen Rocks. But 

 we see here, as repeatedly noticed already, that neither 

 deposit has any relation to the stratification of the slate, 

 which had sustained extensive dislocation before the deposit 

 of the old red sandstone had begun. The cut annexed 

 represents the appearances at this place. 



The sandstone strata here alternate with beds of limestone 



Fig. 27. 



a, slate ; b b, "beds of white siliceous limestone ; c, sandstone 

 and conglomerate. 



and conglomerate, as shown on the figure annexed (fig. 27). 

 The lowest bed, b, next the slate, a, is a hard crystal- 

 line white limestone, about six feet thick ; it contains 

 quartz pebbles, schist, and diffused siliceous matter, and 

 is without fossils. There are several beds higher in the 

 series, but the thickness is less. The total thickness of the 

 various beds is not more than fifty feet. Whin dikes tra- 

 verse both the slate and sandstone. The presence of this 

 peculiar limestone fixes the age of the deposit, which 

 resembles in all respects that already noticed at Achab farm 

 and the Fallen Rocks, as forming a gradation from the Old 

 Red to the carboniferous series there being a difficulty in 

 determining to which it ought to be assigned. We are 

 inclined to the view that it is the lowest member of the 

 carboniferous system. The occurrence of the limestone here 



