THE FRESH- WATER LOCHS OF SCOTLAND. 389 



area of over 200 feet to the west of this is three-quarters of a mile long, 

 and has a maximum depth of 220 feet. The larger area of over 200 

 feet is 2 miles long, and extends from just west of the narrows 

 eastward. The area of over 250 feet lies well down the loch, coming 

 to within 1J miles of the outflow, and includes the maximum depth of 

 the loch, 281 feet. The mean depth of the loch is 104 \ feet. The 

 proper basin of the loch terminates three-quarters of a mile from the 

 lower end of the loch. At this point there is a bend at right angles to 

 the main axis, and there ex'tends a broad, tortuous, shallow section of 

 the loch, with a greatest depth of only 43 feet, and numerous small 

 islands. 



As is shown by the narrowness of the areas enclosed by the deeper 

 contours, there is no marked indication of the U-shaped section of 

 valley lochs excavated by glaciers. The promontory opposite the river 

 Quoich, occurring where a great bend of the axis takes place, must 

 have caused a narrowing here before the delta of the Quoich was laid 

 down. 



On May 6, 1903, the difference of temperature between the surface 

 and 150 feet was under 1 : Surface, 41-9 Fahr. ; 50 feet, 41-2; 150 

 feet, 41-0. 



Loch Poulary (see Plate XCIV.). A long, irregular, narrow loch 

 running east and west in Glen Garry, between Loch Garry and Loch 

 Quoich, about 4 miles distant from the former and 2 miles from the 

 latter. It is little more than a series of expansions of the river Garry, 

 and its limits are accordingly not easy to define. The portion surveyed 

 begins at Eilean Dubh, extends eastward for 1 mile as a narrow channel 

 varying from 9 feet to 23 feet in depth, and then expands into a little 

 basin half a mile long by one-fifth of a mile in greatest breadth. The 

 length of the whole loch is 1J miles, and the mean breadth one-tenth 

 of a mile. The area of the surface is about 91 acres, and the drainage 

 area, which includes Loch Quoich, is 82 square miles. The volume of 

 water is 39 millions of cubic feet. The Allt a' Ghobhain, a considerable 

 stream, and some small burns, enter on the north shore. From spot- 

 levels on the shores, the height of the loch above the sea was estimated 

 to be 320 feet. The greater part of the loch is shallow, but in the 

 eastern basin there is deeper water in the centre, forming, however, 

 only a narrow channel. The maximum depth is 47 feet, the mean 

 depth 10 feet. 



There was a difference of only 1 in temperature between the 

 surface (53-8 Fahr.) and a depth of 40 feet (52-8) on September 28, 

 1903. 



(,'arry (see Plate XCV.). Loch Garry is one of the most 

 important lochs in the basin, being inferior in size only to Loch Ness 



