THE FRESH- WATER LOCHS OF SCOTLAND. 



63 



The temperature of the surface water near the boathouse, when com- 

 mencing the survey at 2.45 p.m. on April 17, was 50'8 Fahr., but 

 later on, out in the open water, the surface temperature was 44'2 

 Fahr. ; on the 18th at noon the surface temperature near the shore 

 was 50-0 Fahr., while in the bay to the north of the boathouse the 

 temperature was 46-0 Fahr. 



Lochan Beinn Caorach and some other small basins of water in 



FIG. 17. HERONS' NESTS ON EILEAN MOLACH IN LOCH BA. 

 (Photograph by T. N. Johnston, .!/.., C.M., F.R.S.E.) 



this region were without boats and could not be sounded; they were 

 evidently all quite shallow and of the same character as Loch Buidhe. 



Loch Laidon (see Plate XVII.). Loch Laidon (or Lydoch, or 

 Luydan) lies partly in Perthshire and partly in Argyllshire, the 

 boundary running along the centre of the western arm and for a 

 certain distance up the main loch. It is one of the best trouting lochs 



