.THE FRESH- WATER LOCHS OF SCOTLAND. 235 



on the north shore, and all around rough peat, rugged hills to the west, 

 gently sloping moor to the south, and low land to the east, through 

 which the Scali burn flows to the Houb, a branch of the Sullom Voe. 

 The loch measures half a mile in length, from east to west, and is a 

 fifth of a mile broad. It is very shallow, with a mean depth of 

 5 feet, and the maximum of 10 feet in the centre. The area is about 

 53 acres, and the volume of water about 11 millions of cubic feet. The 

 area drained slightly exceeds a square mile. The level was not ascer- 

 tained, but is estimated at nearly 100 feet above sea-level. There are 

 many boulders in the loch, along the east and north shores. 

 The surface temperature on July 24, 1903, was 55' 5 Fahr. 



Boer Water (see Plate XCVIII.) is the largest of the lochs of North 

 Eoe. It is nearly in the centre of North Roe, and close to the foot 

 of Ronas hill on its north-east side. It is of roughly oblong form, and 

 measures nearly two-thirds of a mile in length, from east to west, 

 and one- third of a mile in maximum breadth. It is a very shallow 

 flat basin, with a mean depth of only 10 feet, and all, except two very 

 small holes, less than 16 feet deep. In one of these holes, towards 

 the west end, is the maximum depth of 32 feet ; in the more easterly 

 hollow is a solitary sounding of 27 feet, with shallow water all round. 

 There is an island near the south-east shore. 



Roer Water has a superficial area of about 91 acres, and contains 

 43 million cubic feet of water. The Burn of Roerwater flows from the 

 east end of the loch some 2 miles south-eastward into Colla firth. The 

 drainage area extends to 2^ square miles, and includes many small lochs. 

 The level at the date of the survey could not be ascertained ; when visited 

 by the Ordnance Survey on September 28, 1876, the surface was 349 '4 

 feet above sea-level. 



The surface temperature on August 7, 1903, was 54'8 Fahr. 



Clubbi Shuns (see Plate XCVIII.) is a very small loch lying imme- 

 diately to the west of Roer Water, into which it overflows by a short 

 stream. It is of irregular form, and measures a little over a quarter 

 of a mile in length, from east to west, by one-sixth of a mile in greatest 

 breadth. In area, which is about 16 acres, and in volume, 7 millions 

 of cubic feet, it is the smallest of the lochs of North Roe. The loch is 

 very shallow, the greater part of it less than 10 feet deep, only a very 

 small area, somewhat east of the centre, exceeding 20 feet in depth, 

 with a maximum of 28 feet. The drainage area, of rather more than 

 a square mile, includes many very small lochs and the larger Longa 

 Water, which were not surveyed. The outflow is to the east, the burn 

 passing through a lower loch of Clubbi Shuns (not surveyed) into Roer 

 Water. The level could not be ascertained, but would be somewhat over 

 350 feet. 



The surface temperature on August 6, 1903, was 56'4 Fahr. 



