THE FRESH- WATER LOCHS OF SCOTLAND. 245 



of Shetland, measuring 1| miles in a straight line between the extreme 

 points. The maximum breadth, in the middle, is nearly half a mile. 



The loch forms a simple basin, very shallow near the north end. The 

 bottom slopes very gradually down to 20 feet, after w'uich the slope is 

 steeper. The area over 30 feet deep is very narrow, and includes a very 

 small area of over 40 feet founded on a single sounding of 41 feet. The 

 superficial area is 213 acres, or one- third of a square mile, and the volume 

 of water, 111 millions of cubic feet, shows the loch to be the third largest 

 in Shetland. The area drained, including the Loch of Brow, is nearly 6 

 square miles. The principal streams entering the loch are that from the 

 Loch of Brow, the Burn of Hillwell near the south end, and the Burn of 

 Scousburgh in the north. The outflow is though a narrow bar, the Beach 

 of Spiggie. The surface was only 4*0 feet above the level of the sea on 

 July 3, 1903, as compared with 3'8 found by the Ordnance Survey on 

 October 24, 1900. 



The temperature was uniform throughout, viz. 56'8 Fahr. 



Loch of Brough (see Plate XCV.) is a very small loch towards the 

 west side of Bressay. It is the upper loch in the Setter basin, and lies at 

 an elevation of 75'1 feet between two low hills. This elevation was 

 determined on June 30, 1903, when the water was very low, and liable to 

 rise 3 feet higher; when visited by the Ordnance Survey officers on June 

 14, 1876, the level was 77*6 feet above the sea. It is of oblong form, 

 measuring nearly one-third of a mile from north to south, by one-eighth of 

 a mile in greatest breadth, at the north end. It is flat-bottomed, with a 

 mean depth of 2 feet, and a maximum of 4 feet. The area is 19 acres, 

 the volume 2 millions of cubic feet, and the drainage area is half a square 

 mile. A small burn flows a quarter of a^mile north into the Loch of 

 Setter. There is a deposit of peat and sand on the south-east end of the 

 loch. The loch was lowered by a drain some years ago, in order to allow 

 carts to pass along the shore. The surface temperature was 55'6 Fahr. 



Loch of Setter (see Plate XCV.) is a very small loch close to the 

 shore of the Voe of Cullingsburgh, on the east side of Bressay, at a height 

 of 43*2 feet above the sea. This elevation was found both- by the Lake 

 Survey on June 3u, 1903, and by the Ordnance Survey on June 14, 1876 ; 

 this is practically the lowest level, and the water may rise 3 feet higher. 

 It is almost circular, measuring one-fifth of a mile in greatest diameter. 

 It is in all respects by far the smallest loch in Shetland. Its greatest 

 depth is 2 feet, and its mean depth 1 foot ; the surface area is 14 acres, and 

 the volume of water, half a million cubic feet, is one-third of that of the 

 Loch of Brough, the nearest to it in size. The drainage area, which 

 includes the Loch of Brough, is rather more than a square mile. When 

 surveyed the loch was much overgrown with weeds. The surface 

 temperature was 56 D> 3 Fahr. 



