38 ON THE PARALLEL ROADS 



the spot where it is first observed on the hill of Bohuntine. 

 Neither of these shelves are ever met with afterwards, in any 

 tAcn below these points of termination. Shelf 4th, which is at 

 an elevation below tliat of the high semicircular plane just men- 

 tioned, does not bend into it like the other two ; but the hills 

 nearest the river beginning now to sink in height, it continues 

 to run in a more direct sweep towards the foot of Craig-dhu. 

 From the base of this more retired, and more elevated hill, an 

 apparently mossy, and considerably inclined plane, stretches 

 for half a mile in a south-west direction, towards the point of 

 junction of the rivers Roy and Spean. But just above the 

 spot where these streams unite, this plane again rises into the 

 circular and isolated rock called Metildary, which is particu- 

 larly laid down in the map, and which may be easily recogni- 

 zed in Plate II. as being near the eye, and just beyond the 

 mouth of the valley of Glen Spean. Shelf 4th, as it sweeps 

 from Glen Roy around the base of Craig-dhu into Glen Spean, 

 applies exactly in level to the upper line of the inclined mossy 

 plane, lying between Craig-dhu and Mealderry ; and the top 

 of the isolated rock of Mealderry, rising somewhat above this 

 level, is surrounded by a partial delineation, of what the level- 

 ling instrument proves to be an independent portion of the same 

 shelf. 



Although Craig-dhu, which may be properly considered as 

 the mountain dividing Glens Roy and Spean from one another, 

 thus appears to retreat backwards above, from the actual point 

 where the rivers meet, yet the entrance of Glen Spean is very 

 much confined, by the advance of the lower rock of Mealder- 

 ry, on the north side of the valley, towards the base of the 

 mountain on the south side. These come bending from Ao- 

 nachmore, a mountain of the Ben Nevis groupe, and making a 

 vast sweep around the great hollow basin, in the country be- 

 low 



