1858.] MUBCHISON NORTHERIf H1GHLAOT)S, ETC. 389 



such rocks are well exposed where the principal feede of Loch Affiric 

 escapes from the higher moorlands into that fine sheet of fresh water 

 from the highlands of Kintail, and at a pass and ford called '* Aa 

 naMullich*." 



I further believe that the regularly-bedded limestones, which are 

 intercalated in the chloritic and quartzose rocks of Dumbartonshire, 

 and are seen on both banks of Loch Fyne, and also in terraces to the 

 north and west of Inverary, may be classed with some of the oldest 

 of those stratified masses which, like the limestones of Sutherland, 

 are unquestionably of Lower Silurian age. For these calcareous 

 bands also pass under vast masses of mica-schist and quartzose- 

 gneissic rocks. Moreover, as one who has explored the wilds of the 

 Breadalbane deer-forests, I think that the vast expanses of quartzi- 

 ferous flagstones, mica-schists, &c., are simply the prolongations of 

 those rocks of the North-western Highlands, which have here been 

 treated of. Undulating at shght angles of inclination through Glen 

 Orchy, and clasping round the granite of Ben Cruachan on the one 

 hand, or pierced by the porphyries of Glencoe on the other, these 

 flag-like strata, occasionally passing upwards into clay-slate, extend 

 to" the S.E. in broad curves, over the region of the Moor of Eannoch, 

 and around the Black Mount ; whilst along the banks of Loch Tay 

 they contain regularly-bedded limestones, which in their turn dip to 

 the S.E. under other schistose rocks. 



In following them to their south-eastern frontier in Dumbarton- 

 shire, where these rocks, terminating upwards in clay- slates, are sur- 

 mounted by the Old Eed conglomerate and sandstone, we may indeed 

 speculate upon the unfolding in such tracts of the equivalents of 

 younger and higher strata than any which are observed in the 

 northern counties. Thus, the chloritic schists of Ben Lomond, con- 

 taining pebble-beds which underhe the clay-slates, may prove to be 

 the equivalents of some of the Silurian conglomerates of the S.W. 

 coast of Scotland. Let us hope that the day may come when fossils 

 will be discovered in some of those regularly-stratified masses of such 

 varied lithological composition, and thus enable us to speak of their 

 age with the same decision which has been applied to the crystalline 

 strata of the west of Sutherland. 



Looking at the Highlands as a whole, it is essential to observe 

 that, in proceeding from north to south, the geologist meets with 

 vastly larger masses of intrusive rock than in the typical tract of 

 Sutherland. Thus, the edges of the huge granitic Grampians, alone, 



* I hope that my Highland pride may be pardoned if I attach great interest 

 to this gorge, seeing that my ancestor Colonel Donald Murchison (whose brother, 

 my great grandfather, was killed at the battle of Sheriff Muir) selected it as the 

 spot where, in the year 1716, he so placed the native Highlanders under his 

 command, all of them Jacobites, as well as their chief, the exiled WiUiam Earl 

 of Seaforth, whose lands he was defending, that he successfully resisted and beai 

 back the troops of Greorge I., who in vain endeavoured to take possession of 

 Kintail ; and hence these mountains were held for their noble owner, who was 

 eventually pardoned. I live in the hope that my eminent friend Sir Edwin 

 Landseer will soon fulfil his promise, and gratify me by producing a painting of 

 this scene, the history of which is well known to all old Ross-shire Highlanders, 



