270 



BATHYMETRICAL SURVEY OF 



C-D is taken across the loch in the position of the deepest sounding. 

 The areas between the consecutive contour-lines drawn in at equal 

 intervals, and the percentages to the total area of the loch, are as 

 follows : 



to 50 feet 658 acres 28-6 per cent. 



50,, 100 

 100 150 

 150,, 200 

 200,, 250 

 Over 250 



582 

 418 

 272 

 220 

 155 



2305 



25-2 



18-1 



11-8 



9-6 



6-7 



100-0 



The regularity of the average slope of the bottom is indicated by 

 the gradually decreasing areas between the contour-lines, and the 

 comparatively large area within the deepest contour indicates the 

 flat-bottomed character of the deeper part of the loch. 



Loch Fannich was surveyed on August 13 and 14, 1902, and the 

 elevation of the lake-surface was found, on commencing the survey, to 

 be 821 '9 feet above sea-level, which is identical with the level observed 

 by the Ordnance Survey on May 27, 1870. 



Temperature Observations. The temperature of the surface water 

 during the two days spent on the survey varied from 52'7 Fahr. to 

 58 00 1. Two serial temperatures were taken on August 14, 1902, with 

 the following results : 



Each of these series shows a range from surface to bottom of about 

 8J. The temperature was higher in the upper 40 feet of water towards 

 the west end of the loch than in the deep water towards the east end, 

 but at the depth of 100 feet the temperature was 2 lower in the former 

 position. Off Rudha Mor there was a fall of 2-5 between 40 and 70 

 feet, and a further fall of 33 between 70 and 100 feet (equal to 5'8 in 



