Dr. Mac Culloch on the Parallel Roads of Glen Roy. 327 



Having passed Glen Turk, the three lines now become distinct 

 and well marked on the right side, where the hill is covered with a 

 thick alluvium : on the opposite side they are also distinct, although 

 here and there slight appearances of irregularity, and supernume- 

 rary marks occur. The bottom of the glen continues to exhibit an 



many of them being objects of general curiosity, even when not particularly connected 

 with this subject. feet. 



Upper line of Glen Roy, above the Western sea at Loch Eil 1262 



Ditto above the German sea 1266 



Lowest line of ditto, above the Western sea 976 



Upper line of ditto, above the land at Loch Oich 1 180 



Lowest line of ditto, above the same 886 



Upper line above the second of Glen Roy 82 



Second line above the lowest ditto 212 



Upper line of Glen Roy, above the junction of the Roy and Spean 927 



Lowest ditto, above the same place .... 633 



Upper line of ditto, above the bottom of the Glen where the Roy enters it . . 283 



Height of the bottom at that place above the lowest line 11 



Upper line of Glen Roy above Loch Spcy 63 



The bottom of Glen Roy at its upper end, above its bottom at the junction of 



the Roy and Spean ; or its declivity ' 644 



Height from the junction of the Roy and Spean to the sea 343 



Observed upper line of Glen Gloy, above the Western sea 1274 



Difference of level between ditto and the upper line of Glen Roy 12 



Height of Loch Spcy above Garvamore 294 



Ditto above the G erman sea 1203 



Height of Garvamore, or fall of the Spey hence to the sea 909 



Depression of the eastern barrier of Loch Laggan, below the upper line of 



Glen Roy 432 



Whatever doubts we may have respecting the general value of the method by which 

 the elevation of the upper line of Glen Roy was ascertained, I must here remark that this 

 principal measurement receives confirmation, to a certain extent at least, by comparison 

 with the height of that land which is the common division of the Truim and the Garry. 

 This point has been found by levelling to be 1460 feet, and it appears probable from 

 comparing the course of the former river and that of the Spey to their common junc- 

 tion, that the source of the Spey cannot be materially different in elevation; a circum- 

 stance confirmed by the barometric observations. The other measurements in the table 

 scarcely admit of any material errors. 



2 t 2 



