26 



BATHYMETRICAL SURVEY OF 



This table shows that the average slope of the bottom is regular, the 

 areas decreasing with increase of depth, and that the loch partakes of a 

 flat-bottomed character, as evidenced by the comparatively large area of 

 the lake-floor covered by more than 200 feet of water. 



Temperature Observations. Two series of temperatures were taken in 

 Loch More, one towards the north-west end at 5.15 p.m. on September 5, 

 and the other in the deepest part of the loch at 2 p.m. on September 6, 

 with the following results : 



i. ii. 



Denth in feet September 5, 1902, 5.15 > September 6, 1902, 2 p.m., 

 eet< p.m., near N.W. end deepest part of loch in 

 in 101 feet. 294 feet. 



These series show a total range in temperature of 8-7 from surface to 

 bottom in the middle of the loch, and of 3*1 in the 100 feet of water 

 towards the north-west end. In both series a fall exceeding 2J was 

 recorded between 50 and 100 feet, but the greatest fall observed was 

 between 103 and 106 feet in the middle of the loch a fall of 3-3 in the 

 3 feet of water, or more than 1 Fahr. per foot of depth. The readings 

 taken towards the north-west end are all slightly lower than those taken in 

 the middle of the loch at corresponding depths. 



Seiches. Seiches were observed on Loch More on September 2 and 5, 

 1902, the amplitude in each case being about half an inch, but the period 

 could not be accurately determined. The fundamental period was about 

 eleven minutes. 



Loch na h-Ealaidh (see Plate VIII.). Loch na h-Ealaidh is a small 

 shallow basin at the north-west end of Loch More, the narrows between 

 them being crossed by stepping-stones, and having a depth of 1 foot on 

 the date of the survey. The loch is irregularly subcircular in outline, 

 with a maximum diameter of less than half a mile, its waters covering 

 an area of about 64 acres. The maximum depth of 8 feet was observed 

 towards the north-west end, where the river an Earachd flows out, and 

 the great majority of the soundings were taken in depths exceeding 5 feet. 

 The volume of water is estimated at 13 million cubic feet, and the mean 

 depth at 4| feet. The loch was surveyed on September 6, 1902, the 



