34 Mr. J. Bryce's Notices of a late Visit 



theory. I have merely in view the much more humble object 

 of putting on record a few facts, which seem to have escaped 

 the notice of previous observers ; and of offering, in connexion 

 with these, some remarks on the two theories last proposed. 

 I refer to those of Mr. Chambers of Edinburgh, and Mr. 

 James Thomson of Glasgow, both published early in 1848; 

 the latter immediately before my visit, which took place in 

 July of that year. My examination of the district had thus 

 additional interest given to it, as the facts were to be viewed 

 under a somewhat novel aspect, and had not yet been com- 

 mented on by any geologist, with reference to their bearing 

 upon the two theories in question. 



Mr. Chambers's account of the Parallel Roads, with his 

 theory of their origin, forms a portion (pp. 95-130) of his 

 valuable and beautifully illustrated work on Ancient Sea- 

 Margins. A map of part of Lochaber, showing the shelves 

 in the glens, is given at the end. It has been " constructed 

 by Messrs. W. and A. K. Johnston under the direction of 

 Sir George M c Kenzie, Bart., David Milne, Esq., and Robert 

 Chambers, Esq." The same map accompanies a late paper 

 on the Parallel Roads, by Sir George M c Kenzie (Ed. N. Phil. 

 Journ., vol. xliv.) ; it is that to which Mr. Milne refers in his 

 late important paper (Ed. N. Phil. Journ., vol. xliii. p. 339); 

 and on which the reasonings of Mr. James Thomson are 

 founded, an enlarged copy of it having been laid before the 

 Royal Society of Edinburgh along with his paper. 



Now, this map contains an important topographical error, 

 calculated to mislead those who may frame theories of the 

 Roads without having made a personal inspection of the ground. 

 The error consists in this — that at its junction with Glen 

 Fintec, Glen Gluoy is laid down as opening towards Loch 

 Lochy ; whereas, in point of fact, the high ridge descending 

 from the table-land at the top of Glen Toorat, and shutting 

 in Glen Gluoy on the west, continues its course southwards 

 fully a mile below the point where Glen Fintec opens into 

 Glen Gluoy. Glen Fintec is thus completely ad off from direct 

 connexion with Loch Lochy, the ridge in question being con- 

 tinuous throughout, and rising to the height of from 1200 to 

 1800 feet above the sea, or from 300 to 700 feet above the 

 upper shelf. The rocks of which the ridge consists are chiefly 

 micaceous slate and quartzite, the strata being nearly on end, 

 and ranging in the direction of the ridge, or about S.W. I 

 could detect no traces of scratching or grooving, though the 

 rocks are laid bare in many places, and strew the surface in 

 huge flat masses. 



The error now pointed out involves another in the repre- 



