THE FRESH- WATER LOCHS OF SCOTLAND. 131 



and nearly half a mile in length, with a maximum breadth of one-fifth of 

 a mile. The superficial area is about 32 acres, and the drainage area 

 exceeds half a square mile. The maximum depth of 55 feet was taken 

 towards the southern end. The volume of water is estimated at 36 million 

 cubic feet, and the mean depth at 251 f ee t. The basin is simple, the 

 deeper water lying in the southern portion of the loch, the upper end 

 being comparatively shallow, with weeds in the northern angle. Off the 

 south-western shore the slope is steep, soundings in 26, 27, and 35 feet 

 having been taken close inshore ; and off the central part of the opposite 

 shore a sounding in 38 feet was taken a short distance out. The deepest 

 part of the loch is flat-bottomed in character, no less than three consecutive 

 soundings being taken at the maximum depth of 55 feet, and the area of 

 the lake-floor covered by more than 50 feet of water is equal to 16 per 

 cent, of the total area, while that covered by less than 25 feet of water is 

 equal to 58 per cent. The loch was surveyed on April 28, 1905, when 

 the elevation was 171 '8 feet above the sea. The temperature of the water 

 varied to the extent of less than 1 Fahr. from surface to bottom, the 

 reading at the surface being 46^5 ; at 25 feet 46'2 ; and at 53 feet 45'6. 



Kirk Loch (see Plate XL VII.). Kirk Loch lies to the south of Mill 

 Loch, and to the west of the northern portion of Castle Loch, into which 

 it drains by the Vendace burn. It is surrounded by stony fields, a circular 

 hill, called Castle hill, rising between it and Castle Loch. Kirk Loch trends 

 nearly north and south, and is less than half a mile in length, covering 

 an area of about 33 acres. Tbe maximum depth of 25 feet was taken 

 towards the northern end, the mean depth being 10 feet, and the volume 

 of Avater 15 million cubic feet. The basin is simple, with the deeper 

 water occupying the northern portion of the loch, soundings in 12 and 

 13 feet being taken quite close to the northern end. More than half the 

 lake-floor is covered by less than 10 feet of water. The loch was surveyed 

 on April 28, 19<>5, when the elevation was 157*15 feet above the sea. 

 The temperature of the water was practically uniform throughout, the 

 reading at the surface being 47-4 Fahr., and at 23 feet 47-2. 



Castle Loch (see Plate XL VII.). Castle Loch, the largest within the 

 basin, is situated immediately to the south of Lochmabeu. The shores 

 of the loch are gentle, grassy slopes, with patches of wood, and there is 

 a fringe of weeds nearly all round; the eastern shore where free from 

 reeds is stony. It receives the drainage from Mill and Kirk Lochs, and 

 the outflow is by a large burn (Valison burn) at the southern end through 

 a peaty flat. The loch is subtriangular in outline, the length from north- 

 west to south-east exceeding three-quarters of a mile, the maximum breadth 

 across the wide southern portion being two-thirds of a mile, while the 

 mean breadth is one-third of a mile. The superficial area is about 193 acres, 

 or nearly one-third of a square mile, the drainage area extending to nearly 



