THE FRESH- WATER LOCHS OF SCOTLAND. 327 



3 p.m. on the date of the survey in the deepest part of the loch, with 

 the following results : 



Surface 54'6 Fahr. 



5 feet 54-6 



10 . 54-5 



25 ,, 54-2 



50 ,, 54-0 



100 53-3 



120 53'0 



135 52-l 



150 ,, 49-2 



This series shows a range from surface to bottom amounting to 

 5*4. The upper layers of water are practically uniform in temperature, 

 the decrease from the surface down to 50 feet being only 0> 6, down to 

 100 feet l-3, and down to 120 feet l-6, whereas between the depths 

 of 120 and 150 feet the fall of temperature was 3-8. It was stated 

 that the loch freezes all over in winter. 



The details regarding the lochs in the Naver, Borgie, Kinloch, and 

 Hope basins are collected together in the table on p. 326 for convenience 

 of reference and comparison. From this table it will be seen that in the 

 eleven lochs under consideration over 1400 soundings were taken, and 

 that the aggregate area of the water surface is over 11 square miles, so 

 that the average number of soundings per square mile of surface is 127. 

 The aggregate volume of water contained in the lochs is estimated at 

 about 15,600 millions of cubic feet. The area drained by these lochs 

 is about 239J square miles, or twenty-two times the area of the lochs. 



NOTES ON THE GEOLOGY OF THE DISTRICT BETWEEN LOCH HOPE AND 



STRATH NAVER. 



By B. N. PEACH, LL.D., F.R.S., and J. HORNE, LL.D., F.R.S. 



The district extending from Loch Hope to Strath Naver, in the 

 north of Sutherland, has not yet been wholly mapped by the Geological 

 Survey. 



The north-western tract, embracing the lower part of Loch Hope, 

 comes within the belt of territory affected by the Post-Cambrian move- 

 ments to which reference has been made in the description of the geology 

 of the districts of Loch Assynt and Loch Maree.* Hence, on the hill- 

 slopes on either side of the river Hope, we find various subdivisions of 



See pp. 178 and 233. 



