174 Charles Maclaren, Esq., on Grooved and Striated Rocks 



east and west The surface was wet with rain ; in a dry day 

 they would have escaped observation. 



Loch Lubnig — Arrow 12. — Strise were seen on the east 

 side of the loch, close to the road, one mile from the south 

 end. They ran noi*th and south, were on a surface highly 

 inclined, and would not have been visible if the rock had 

 not been wet. 



Loch Katrine — Arrow 11. — At one spot on the north side, 

 near the east end, striae were seen, running nearly E. and W. 

 on a horizontal surface. 



Callender — Arrow 13. — On the top of the hill, which rises 

 like a wall behind the village, I found grooves running 

 nearly east and west. The hill consists of beds of coarse con- 

 glomerate, mixed with beds of red sandstone, all very highly 

 inclined. The grooves were on a portion of the edges of the 

 sandstone, which was nearly level. 



I consider the proofs of an easterly motion in the grooving 

 agent at Loch Earn and Comrie, to be quite conclusive, and 

 on the strength of this evidence, have assumed that the mo- 

 tion was easterly also at Loch Katrine and Callender, and 

 southward at Loch Lubnig, as the arrows 11, 12, 13, indicate. 

 The dotted line in the map, extending from Bute to Crieff, 

 and onward to the River Tay, shews the junction of the old 

 red sandstone and clay-slate, and marks the eastern boundary 

 of the mountainous country. 



Horizontal groovings are seen at the west end of the 

 Crinan Canal, on a vertical surface (No. 10), a little above 

 the level of the water ; but there is nothing to indicate in 

 what direction the object which caused them moved. 



In the basin of the Forth the striae run in lines approach- 

 ing to east and west ; and the appearance of the hills, which 

 present the phenomena of ci'ag-and-tail, entitles us to con- 

 clude that the agents which produced the striae moved from 

 the west to the east. In the map an attempt has not been 

 made, except in a few instances, to give the du-ection of the 

 lines within less than one point of the exact bearing, many 

 of the observations having been made some years ago, when 

 a minute attention to this matter was not thought necessary. 

 Some of them, too, are on vertical surfaces, and so placed as 



