37 



very close, the sandstone dipping at a small angle towards the nearly 

 vertical slate; and in Campsail Bay a considerable space of flat 

 beach intervenes, concealing the contact. The line of junction 

 passes near the Saw-mill, and across the upper part of the fields 

 sloping down from the northern edge of the plantation which crowns 

 the heights on the south side of the great hollow or dingle. 



On the southern coast of Portkill the sandstone dips for a short 

 distance toward the south ; the dip then changes, and continues in 

 other parts to be between west and south-west, at an angle of about 

 15 to 20. About Tnellan, and thence to Toward Point, the old 

 red with subordinate beds of limestone occupies the coast, occurring 

 in small patches over the slate, extending, however, no farther 

 inland than the well marked terrace which exists here, whose front 

 shows the slate rock from base to summit. But neither in the 

 sandstone nor limestone have fossils yet been found. Similar 

 limestone bands occur in the old red on the opposite coast at 

 Innerkip ; and at the south base of Benlomond they descend to the 

 very bottom beds of the old red, not far from the mica slate. In 

 none of these localities have we ever found any fossils save a few 

 crushed bivalves. The English cornstones (Momnouth and Pem- 

 broke) have yielded some ichthy elites (ceplwlaspis) . The most 

 considerable body of cornstone in the West of Scotland is at Kil- 

 chattan, in Bute, to which reference will again be made, 



28. The coast section of Renfrewshire presents only old red sand- 

 stone and trap with occasional beds of limestone. The sandstone 

 rises seaward, dipping east and south-east, at a small angle, and 

 everywhere occupies the coast except at Kempoch Point and 

 Cloch Point, where the overlying trap reaches the coast line, and is 

 seen between high and low water, resting upon and altering the 

 sandstone. The great overlying mass of trap sends out innumerable 

 dikes intersecting the sandstone of the coast, and running in very 

 various directions, but with a general tendency to the west and 

 north-west. Into a minute description of these, and the changes 

 produced by them upon the rocks which they intersect, we cannot 

 enter in this place. One instance only will be given, as bearing 

 upon the changes induced on limestone. This rock appears in two 

 places near Innerkip ; one bed extends from the bridge on the 

 Greenock road, at the north end of the village, up into the hill on 

 the south-east of the village, rising with the slope of the sandstone 

 beds, and preserving a thickness throughout, of about twelve feet ; 

 it has been extensively quarried behind -the village, but is now little 

 worked. As it is extremely hard, and contains much chert dis- 



