228 
BATHYMETRICAL SURVEY OF 
observed in the centre of the loch near the northern end. The area of 
the lake-floor covered by less than 25 feet of water is about 56 acres, or 
96 per cent, of the total area. 
T emperature Observations . — Temperatures taken at 5 p.m. on July 
28, 1902, in the deep part of the loch gave the following results : — 
Surface ... 
5 feet ... 
7 „ ... 
15 „ ... 
25 „ ... 
57° ‘5 Fahi 
57° -5 ,, 
57° -5 ,, 
57°T „ 
56° 0 ,, 
Loch a’ Bhaid-Luachraich (see Plate L.). — Loch a’ Bhaid-Luachraich 
(or Goose Loch) lies about a mile to the east of Loch Ewe, into which 
it drains at Aultbea by the Allt Bheithe. It is surrounded by low, 
rounded hills, steep only towards the south-east, covered with peat or 
morainic material. It is extremely irregular in outline, and in fact 
may almost be looked upon as two lochs with a connecting arm. The 
south-western part is shallow, the maximum depth observed in it 
being 43 feet, while the north-eastern part is much deeper, having a 
maximum depth of 143 feet ; the maximum depth observed in the 
connecting arm was 15 feet. The lower part where the stream leaves 
the loch is thickly overgrown with reeds and rushes, and weeds are 
abundant in the two bays at the head of the loch. It was surveyed 
on July 29 and 30, 1902, and the elevation was determined, by levelling 
from bench-mark, as being 309-6 feet above the sea; when levelled by 
the officers of the Ordnance Survey on August 3, 1870, the elevation 
was found to be 310-5 feet above sea-level. 
Loch a’ Bhaid-Luachraich is over 1^ miles in length, and over a mile 
in maximum breadth, with a mean breadth of one-third of a mile. It 
covers an area of half a square mile, and it drains directly an area of 
dl' square miles, but since it receives the outflow from Loch Mhic’ 
Hie Riabhaich its total drainage area is nearly 4 square miles — an area 
eight times greater than that of the loch. The volume of water is 
estimated at 486 million cubic feet, and the mean depth at 34 feet. The 
bottom in the south-western part of the loch is rather irregular, while 
the north-eastern part forms a simple deep basin, the maximum depth 
of 143 feet having been observed near the centre at the widest part of 
this portion. Section A-B is taken across this wide portion at the 
position of the deepest sounding. The areas between the consecutive 
contour-lines, and the percentages to the total area, are as follows : ■ — 
0 to 
25 feet 
184 acres 
56 -2 per cent. 
•25 „ 
50 ,, 
84 „ 
25 ’5 ,, 
50,, 
75 „ 
17 ,, 
5-3 
75 ,, 
100 „ 
17 „ 
5-0 
Over 
100 ,, 
26 „ 
8-0 
3-28 
100-0 
