6 BATHYMETRICAL SURVEY OF 



of about 120 acres, and receiving the drainage from an area of three 

 quarters of a square mile. Its superfluent water is carried by a short 

 stream into the neighbouring Loch Leum a' Chlamhain, lying less than 

 a quarter of a mile to the east. The maximum depth of 33 feet was 

 observed comparatively close to the south-eastern shore. The volume 

 of water is estimated at 60 million cubic feet, and the mean depth at 

 11 J feet. The loch was surveyed on October 20, 1902, but the elevation 

 above the sea could not be determined; when visited by the officers of 

 the Ordnance Survey on June 10, 1870, the elevation was found to be 

 800*5 feet above sea-level. 



Loch Coire nam Meann forms a simple basin, but the north-western 

 portion is comparatively shallow, the deeper water occurring in the south- 

 eastern portion, the deepest sounding having been recorded less than 200 

 yards from that shore. The deep water, however, is of limited extent, for 

 only 15 per cent, of the lake-floor is covered by more than 20 feet of 

 water, while about one half of the lake-bottom is covered by less than 10 

 feet of water, as shown in the following table : 



Feet. Acres. Per ceiit. 



OtolO 58 ... 49 



10 20 43 ... 36 



over 20 18 15 



119 100 



The temperature of the surface water at 3 p.m. on October 20, 1902, 

 was 45'0 Fahr. 



Loch Leum a' Chlamhain (see Plate II.). Loch Leum a' Chlamhain (or 

 (Leum-na-Clavan, or Leum-a-Chamblain) is a fine fishing loch, like its 

 neighbour Loch Coire nam Meann, famous for the large size of its trout 

 and for the heavy baskets frequently recorded; like its neighbour also 

 it is strictly preserved. Ben Griam Mhor lies to the south, and Ben 

 Griam Bheag to the east. The outflowing water is carried by the Allt 

 Airidh-dhamh into Loch Araich-Lin. The loch trends nearly north and 

 south, and is If miles in length. It varies greatly in width, with a 

 constriction in the central part, the maximum breadth exceeding half a 

 mile towards the northern end of the loch, the mean breadth being one- 

 third of a mile. Its waters cover an area of about 350 acres, or over half 

 a square mile, and it drains directly an area of nearly four square miles, 

 but since it receives the outflow from Loch Coire nam Meann its total 

 drainage area is about 4f square miles. The maximum depth of 51 feet 

 was observed near the southern end of the loch, while towards the 

 northern end a depth of 50 feet was recorded. The volume of water 

 is estimated at 298 million cubic feet, and the mean depth at 19^ feet. 

 The loch was surveyed on October 20, 1902, but the elevation above the 

 sea could not be determined ; when levelled by the Ordnance Survey 



