OP LOCHABEn. 3 



likely to explain the circumstances of their particular forma- 

 tion. My remarks will, I hope, be found more intelligible, by 

 reference to a map, which, however, must be considered as a 

 mere eye-sketch of the country, its construction having been 

 merely aided by the observation of a few angles and bearings, 

 and therefore having no pretensions to geographical accuracy, 

 beyond what is necessary for the purpose to which it is de- 

 dicated, — that of giving an idea of the courses of the dif- 

 ferent shelves, to which I have affixed distinguishing fi- 

 gures. Though the shelves are laid down in continuous 

 lines, it is by no means meant to convey the idea, that 

 they are strictly so in reality : partial deficiencies in their con- 

 tinuity are certainly to be observed, but these are too trifling 

 and unimportant, to be noticed in a general view of them on 

 so small a scale. It should be also remembered, that it is on- 

 ly in the most important points, that the detail of their vari- 

 ous lesser bendings is attended to. Where such a point oc- 

 curs, as at the head of Lower Glen Roy, the attention which 

 has been paid to mark the sinuosity of the lines, as correctly 

 as possible, has compelled me to devote more room to that 

 part, than it would be entitled to were strict proportion obser- 

 ved ; and thus Upper Glen Roy is more reduced in size than 

 it ought otherwise to have been. Besides the map, I have ven- 

 tured to give a few sketches of what appeared to me to be the 

 most remarkable views of the shelves. These are taken from 

 above, or on the same level with them, so as to produce that 

 natural rise of the perspective, observable in the lines of level 

 water. Without this, it is not easy to comprehend their hori- 

 zontality from a drawing. This, however, lends them the cha- 

 racter of bird's-eye views, and consequently gives a more con- 

 fined appearance to the glens than they present when seen 

 from below. There are also two plates of diagrams, which 

 may be found useful in illustrating the theory of their for- 

 mation. 



A 2 GENERAL 



