THE FRESH-WATER LOCHS OF SCOTLAND. 23 



series taken in the deepest part of the loch at 3 p.m. showed that the 

 water was practically uniform in temperature from surface to bottom : 



Surface 51-4: Fahr. 



10 feet 51-4 



20 51-5 



30 51-5 



50 51-5 



80 51-2 



In the nine lochs included in the foregoing table 681 soundings were 

 taken, and the aggregate area of the water-surface is almost 5 square 

 miles, so that the average number of soundings per square mile of surface 

 is 141. The aggregate volume of water contained in the lochs is estimated 

 at about 1319 millions of cubic feet. The area drained by these lochs 

 is 168 square miles, or nearly thirty-five times the area of the lochs. 



