64 ON THE PARALLEL KOADS OF LOCHABER. 



The height of the source of the Truim is here stated to be 

 1460 feet; and it is supposed by Dr MacCulloch not to be 

 materially different from that of the source of Spey, which, 

 however, is only 1203 feet by his measurement. According 

 to this statement, therefore, the source of Truim is 257 feet 

 above that of Spey, which, in a question of so much nicety as 

 the present, must be considered as constituting a very mate- 

 rial difference indeed. But the difference between Dr Mac- 

 Culloch and me, is only about 63 feet, which, if it can be al- 

 lowed me, will bring the height of the sources of the Truim 

 and Spey so much nearer to an equality, and will at the same 

 time make the altitudes relating to Glen Roy, in perfect har- 

 mony with the view of the state of matters which my observa^ 

 tions have led me to entertain. 



II. 



