328 SKY. GEOLOGY. SECONDARY STRATA. 



ammonitse are here more abundant than oi\ the eastern 

 shore, but they are even here so imperfect that little 

 of them can be discovered but their casts in the surface 

 of the rock where it is corroded by the action of the sea. 



With some material interruptions from trap, the beds 

 of limestone and the associated rocks are continued with 

 the same regularity round the point of Swishnish towards 

 Kilbride ; that point being occupied by a mass of sand- 

 stone which will be more properly considered after the 

 limestone, as it is superior in position. 



The only difficulty that occurs in this place is that 

 of the quartz which intervenes between the two masses 

 of unstratified limestone ; nor can I pretend to suggest 

 any other explanation of it than that which has already 

 been proposed on similar occasions. I shall therefore 

 proceed to consider the remaining changes in the cal- 

 careous rocks that are visible through the small space 

 which now remains to be examined. 



To render this description clear it is necessary to return 

 to the original point at Loch Eishort, where the series 

 of beds which follows the unstratified limestone is in 

 contact with it. At the very point of contact there is 

 an interference of the two, which is highly satisfactory, 

 as tending to establish their perfectly consecutive nature, 

 and consequently to determine the place of the former 

 limestone without the shadow of a doubt. Where they 

 meet, two or three laminae of the crystalline limestone 

 alternate with an equal number of the common one ; and 

 they are readily distinguished, because the former being 

 mixed with a hard schist have a superior degree of per- 

 manence, and project on the corroded sides of the latter. 

 The same contact of the two occurs at Kilbride; but 

 the same interference is not visible, although the paral- 

 lelism is perfect. 



From each end of this junction the ordinary limestone 

 beds may be traced all round the point which separates 

 Loch Eishort from Loch Slapin, intersected every where 



