THE FRESH- WATER LOCHS OF SCOTLAND. 75 



depth. The length of the loch is 298 times the maximum depth, and 

 652 times the mean depth. Loch Dochart was surveyed on April 28, 

 1902, and the level of the surface of the water was determined from 

 Ordnance Survey bench-mark as being 513 feet above sea-level. The 

 temperature of the surface water at 11.30 a.m. on that date was 50 0> 1. 



Loch lubhair (see Plate XX.). Loch lubhair (or Nubhair) receives 

 the outflow from Loch Dochart by a river considerably less than half a 

 mile in length, so that they may almost be regarded as forming one lake. 

 It affords fair trout-fishing, and the scenery round about is very 

 beautiful. Loch lubhair is about 1J miles in length, with a maximum 

 breadth of about one-third of a mile, the mean breadth being nearly 

 one-sixth of a mile, or 12 per cent, of the length. Its waters cover an 

 area of about 135 J acres, or over one-fifth of a square mile, and it drains 

 directly an area of about 5J square miles; but, since it receives the 

 outflow from Loch Dochart, its total drainage area is over 44J square 

 miles, or 212 times the area of the loch. Over 100 soundings were taken 

 in Loch lubhair, and the maximum depth observed was 65 feet. The 

 volume of water contained in the loch is estimated at 147,284,000 cubic 

 feet, and the mean depth at 25 feet, or 38 per cent, of the maximum 

 depth. The length of the loch is 110 times the maximum depth, and 286 

 times the K meaii depth. Loch lubhair trends in a north-east and south- 

 west direction, and is rather peculiar in outline, resembling somewhat 

 the italic letter /, constricted in the central portion, where a ridge crosses 

 the loch with a maximum depth of 36 feet on it. The loch widens and 

 deepens on each side of this constriction, the maximum depth of the 

 loch having been found in the north-eastern part, where the loch is 

 widest, the greatest depth observed in the south-western part being 

 49 feet. The 25 -feet basin is a continuous area over a mile in length, 

 approaching close to the northern shore, but distant about a quarter 

 of a mile from the south-west end. The area of the lake-floor covered 

 by less than 25 feet of water is about 72 acres, or 53 per cent, of the 

 total area of the loch ; the area between the 25- and 50-feet contours is 

 about 59 acres, or 44 per cent., while the area covered by over 50 feet 

 of water is about 5 acres, or 3 per cent, of the entire area of the loch. 

 Loch lubhair was surveyed at the same time as Loch Dochart, on April 

 28, 1902, the level of its surface being a foot lower than that of Loch 

 Dochart, viz. 512 feet above the level of the sea. 



Loch Earn (see Plate XXII.). Loch Earn is situated amid lovely 

 surroundings, the hills on both sides being clothed with rich woods, and 

 splendid mountain scenery bounds the horizon towards the west, while 

 on the south Ben Vorlich towers to a height of 3200 feet. It contains 

 trout and salmon, and also Salmo ferox. It has been said that the loch 

 is 100 fathoms ( = 600 feet) deep in some places, but this is disproved by 



