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LAG AND BENAN-HEAD. -We refer in another place to the 

 inducements which Lag offers as a centre for several excursions. 

 Many interesting appearances may be noticed in the vicinity, and 

 in the river banks near, some remarkable dikes. Benan-head 

 is a mass of igneous products, irregularly intermingled, so that 

 the relations of the rocks cannot be well determined. Dark- 

 based felspar porphyry seems disposed in alternate bands with 

 greenstone and basalt, the porphyry prevailing upwards, and the 

 two other rocks in the lower parts. Dikes of newer age intersect 

 the whole series. The entire mass of the headland is wedge- 

 shaped, narrowing downwards, the upper edge being on the same 

 level with the strata of sandstone on either side. The ends of these 

 strata abut against the trap throughout. On the beach westwards 

 there is a dike of red quartziferous porphyry. 



These trap rocks range over the high grounds northwards ; the 

 coast section, as far as Dippen, presenting generally sandstones and 

 marls. The glens inland show similar sections, there being much 

 marl like that in Bein-Leister glen at Lamlash ; but we did not 

 notice any limestone. 



DIPPED. On the road towards Dippen, east of Auchinhew farm, 

 a stream descends over a pretty fall, seventy feet high, called Eis- 

 a-Mhor, into a large open basin, the perpendicular sides of which 

 present a facade of pillars resting on sandstone ; over this is another 

 bed of sandstone, supporting beds of amorphous trap. Dikes 

 traverse the whole series. The map will show the relations of 

 the rocks here which, all the way round to Whiting Bay, 

 strikingly illustrate the intrusive character of trap, and in some 

 places the connection of dikes and overlying masses. There are 

 fine columnar trap ranges about Dippen, and a causeway on the 

 platform of the beach. Kildonan old castle stands on a great bed 

 or dike of trap, continued a little below the level of the water, as far 

 as Pladda island, which is thus attached to the mainland. The 

 island consists of a peculiar greenstone, resting on sandstone. 

 The Duke of Hamilton has lately erected a handsome shooting 

 lodge on a commanding site above the Dippen cliffs. Kildonan 

 castle is an old ruinous square keep, " one of a line of watch-towers, 

 reaching from the mouth of the Clyde to Dumbarton rock. It was 

 originally the residence of a family called Macdonald, who owned 

 lands adjoining. It next passed with the property, by purchase, 

 into the hands of the Stewarts of Kilquheelly, in Bute ; by them it 

 was sold with the rest of their property to the Marquis of Bute, 



