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 sux3erficial 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 25^ feet. 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 oft’ 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 Castfe Loch, into which 
it drains by the Veudace 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. TLe maximum depth of 25 feet was taken 
towards the northern end, the mean depth being 10 feet, and the volume 
of water 15 million cubic feet. The basin is simple, with the deeper 
water occupying the northern portion of the loch, soundiugs 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, 1905, 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 
