232 FRAGMENTS OF SCIENCE 



of their waters causing them to produce but a feeble im- 

 pression upon the mountain sides. From Glen Gluoy we 

 passed down Glen Turrit to Glen Roy, and through it 

 homeward, thus accomplishing two or three and twenty 

 miles of rough and honest work. 



Next day we thoroughly explored Glen Glaster, follow- 

 ing its two roads as far as they were visible. We reached 

 the col discovered by Mr. Milne-Home, which stands at 

 the level of the middle road of Glen Roy. Thence we 

 crossed southward over the mountain Creag Dhubh, and 

 examined the erratic blocks upon its sides, and the ridges 

 and mounds of moraine matter which cumber the lower 

 flanks of the mountain. The observations of Mr. Jamie- 

 son upon this region, including the mouth of Glen Trieg, 

 are in the highest degree interesting. We entered Glen 

 Spean, and continued a search begun on the evening of 

 our arrival at Roy Bridge the search, namely, for glacier 

 polishings and markings. We did not find them copious, 

 but they are indubitable. One of the proofs most con- 

 venient for reference is a great rounded rock by the 

 roadside, 1,000 yards east of the milestone marked three- 

 quarters of a mile from Roy Bridge. Further east other 

 Ceases occur, and they leave no doubt upon the mind that 

 Glen Spean was at one time filled by a great glacier. To 

 the disciplined eye the aspect of the mountains is perfectly 

 conclusive on this point; and in no position can the ob- 

 server more readily and thoroughly convince himself of 

 this than at the head of Glen Glaster. The dominant 

 Mils here are all intensely glaciated. 



But the great collecting ground of the glaciers which 

 dammed the glens and produced the parallel roads were 

 the mountains south and west of Glen Spean. The mon- 



