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PROCEEDINGS OE THE GEOLOGICAL SOCIETY. 



[Feb. 20, 



diagram I have already dilated. Next, in his old sections on Loch 

 Broom, his order of the quartz-rock and limestone, conformably 

 overlain by his " upper gneiss," is equally clear, and is entirely in 

 Unison with the section made by my companion last summer and 

 with my old observations. In short, his " older gneiss " lying be- 

 neath all the other rocks is a, and his " upper gneiss " (6) is high in 

 the ascending series. 



I say, therefore, in citing his own observations and sections, that 

 there is an " upper gneiss ; " and to whatever " old, long-established 

 principles of Scottish geology" Professor Nicol may appeal, I main- 

 tain that the researches of my contemporaries and myself have neces- 

 sarily led to the establishment of the new classification. 



In conclusion, I may say, that our labours during the last 

 summer, as detailed in the preceding memoir, seem to me to have 

 determined the question at issue, by an appeal to the order exhibited 

 over other and very extensive Highland regions. Thus, Mr. Geikie, 

 taking up the survey of the mainland, whilst I was exploring the 

 Laurentian gneiss of the Lewis, has followed the disputed line of 

 junction from Sutherland through mountainous tracts of Ross-shire 

 for more than sixty miles, and, by observing closely a number of 

 transverse sections, has completely established the proofs of a regular 

 and unbroken ascending order from the inferior quartz-rock and 

 limestone into overlying quartzose and micaceous strata (occasionally 

 assuming gneiss-like characters), which, graduating up into chloritic 

 schists and clay-slates, occupy such vast breadths of the north of 

 Scotland. On my own part, I have, during last summer's survey 

 with my associate, so satisfied myself of the existence of the same 

 ascending order, not only in many parts of my native county of 

 Ross, but also by researches in the Southern Highlands, and notably 

 in Islay, as explained in the preceding memoir, that, being now 

 convinced that the principle of classification I suggested is esta- 

 blished on a sound basis, I take my leave of the subject, trusting to 

 Mr. Geikie and my other able colleagues of the Geological Survey, 

 as well as to Professor Harkness and younger geologists than myself, 

 to discover new truths, which may improve or modify my con- 

 clusions. 



On the Coincidence between Stratification and Foliation in 

 the Crystalline Rocks of the Scottish Highlands. By Sir 

 Roderick I. Merchison, " D.C.L., V.P.G.S., F.R.S., &c, and 

 Archibald Geikie, Esq., F.R.S.E., F.G.S. 



[Bead February 20, 1861, but, by permission, printed here in association with 

 the foregoing paper, which has reference to the same country.] 



~No memoir on the crystalline rocks of the Highlands of Scotland 

 can be regarded as complete if it contain no reference to the ques- 

 tion of the " foliation " in that region, as fii'st raised in the year 

 1S52 by the late Mr. D. Sharpe. In our paper which was laid 

 before the Society at the last Meeting, we avoided entering upon 

 this subject, reserving such remarks as we have to offer for a sepa- 



