300 BATHYMETRICAL SURVEY OF 



area of about 370 acres, or over half a square mile, and an area twenty 

 times greater an area of over 11 \ square miles drains into it. The 

 maximum depth of 71 feet was observed not far from the largest island 

 in the loch, and nearer the northern than the southern end. The 

 volume of water is estimated at 415 million cubic feet, and the mean 

 depth at nearly 26 feet. Loch Fiodhaig was surveyed on October 23, 

 1902, but the elevation above the sea was not determined by levelling; 

 judging from the contour-lines, the lake-surface is apparently nearly 

 700 feet above sea-level. The loch is irregular both in outline and 

 conformation. The lake-floor shows undulations, and in some places 

 deep water approaches very close to the shore, as may be seen in the 

 two sections on the map. The areas between the contour-lines, and 

 the percentages to the total area of the loch, are as follows : 



bo 25 feet 203 acres 55 per cent. 



25,, 50 133 36 



Over 50 , 33 , 9 



369 ,, 100 



The temperature of the surface water on the date of the survey was 

 48-0 Fahr. 



Gorm Loch Mor (see Plate LXIX.). Gorm Loch Mor lies about 

 4 miles to the west of the head of Loch Shin, in a mountainous district, 

 with Beinn Leoid (2597 feet) to the north, Beinn Uidhe (2384 feet) to 

 the west, and Ben More Assynt (3273 feet) and Coniveall (3234 feet) to 

 the south. Its outflow is carried through a series of smaller lochs 

 (Fionn Loch Mor, Fionn Loch Beag, and Loch na Sroine Luime), which 

 could not be sounded, into the river Cassley. Though a comparatively 

 small loch, it has the distinction of being deeper than the other lochs 

 in the basin, except Loch Shin. It is very irregular in outline, and 

 includes many islands. The length of the loch, along a straight line 

 from north-west to south-east, is slightly over a mile ; but along a 

 line following the deeper water it is considerably more. The greatest 

 width in a north-and-south direction is over half a mile, the mean 

 breadth of the entire loch being less than a quarter of a mile. Its 

 waters cover an area of about 185 acres, or over a quarter of a square 

 mile, and it drains an area of 5J square miles. Nearly 70 soundings 

 were taken, the maximum depth of 91 feet being observed comparatively 

 close to the western shore. The volume of water is estimated at 196 

 million cubic feet, and the mean depth at over 24 feet. The loch was 

 surveyed on October 22, 1902, when the elevation of the lake-surface 

 was found to be 847*0 feet above the sea ; when visited by the Ordnance 

 Survey officers on October 1, 1870, the elevation was 846-4 feet above 

 sea-level. 



