THE FRESH- WATER LOCHS OF SCOTLAND. 171 



shallow water. The 25-feet contour-line follows approximately the 

 outline of the arm, and the 50-feet area is considerable, the maximum 

 depth being 66 feet in the eastern part of the basin. 



The areas between the consecutive contour-lines, and the per- 

 centages to the total area of the loch, are as follows : 



to 50 feet 672 acres 50 '2 per cent. 



50,, 100 422 31-7 



100,, 150 171 127 



150,, 200 68 5-0 



Over 200 , 5 , 0'4 



1338 ,, 100-0 



Loch Skinaskink was surveyed on September 19 to 23, 1902. The 

 elevation of the lake-surface above the sea on commencing the survey 

 on September 19, 1902, was determined, by levelling from bench-mark, 

 as being 245*1 feet; when levelled by the Ordnance Survey officers on 

 August 13, 1870, the elevation was 242-7 feet above sea-level. The 

 highest drift-mark seen was 3J feet above the surface of the water. 



Temperature Observations. Temperature observations taken in the 

 deepest part of the loch at 4 p.m. on September 20, 1902, gave the 

 following results : 



Surface .. .. ... 54 '2 Fahr. 



10 feet 54-2 



25 54-0 



50 54-0 ,. 



100 ,, 53'3 ,, 



125 50'l 



150 ,, .. .. 50'0 ,, 



170 , '. 49-6 



This series shows a range of temperature amounting to 4 0> 6, the greatest 

 fall being one of 3*2 between 100 and 125 feet. 



