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BATHYMETRICAL SURVEY OF 



The basin of the loch is quite simple, the deepest part being much 

 nearer the north end, and the longitudinal slope is accordingly quicker 

 at the north end and very gradual towards the south. The temperature 

 of the water on October 18, 1904, was 46-0 Fahr. at the surface, the 

 same at a depth of 20 feet, and only a trifling fraction less at the 

 bottom, 45-8. 



FIG. 57. AN DUBH LOCHAN. 



(Photograph by Colonel Mainwaring.) 



Lochan Lfann dd-Shrd (see Plate XC.). A very picturesque loch, 

 almost halfway between Fort William and Ballachulish. It is about 

 5 miles south of Fort William, and is reached by a very rough road, 

 one of General Wade's military roads. It is a narrow loch, with its 

 axis running north-east and south-west. The surrounding hills are of 

 moderate height (1500 to 2000 feet) and grassy, except on the east, 

 where Mullach nan Coirean rises steeply to 3000 feet. Patches of fir 

 wood towards the lower end of the loch enhance the beauty of the 

 scene. 



The loch is nearly a mile long and relatively very narrow, the 

 greatest breadth being only about one-sixth of a mile, and the mean 

 breadth one-eighth of a mile. The maximum depth is 25 feet, and the 

 mean depth 8J feet. The surface has an area of about 66 acres. The 

 volume of water is 23 millions of cubic feet. It receives the drainage 



