206 
BATHYMETEICAL SURVEY OF 
of arenaceous Foraminifera. The mica is present in extremely minute 
flakes, and imperceptible to the naked eye in the unwashed material. 
In this respect the material from Loch Morar differs from that obtained 
in most of the other lochs, in the samples from which the glistening 
mica flakes attract one’s attention. 
Loch Beoraid (see Plate XLIV.). — Loch Beoraid is a long narrow 
loch, lying amidst wild and rocky scenery about 3 miles to the south of 
Loch Morar. There were no Ordnance Survey bench-marks available 
in the vicinity of the loch from which the level of the water surface 
could be ascertained, but, from the position of the spot-levels, the height 
was estimated at 168 feet above the sea. The loch trends in an east-to- 
west direction, and is fed by numerous small burns, the largest, Allt a 
Ghlinne Dhuinn, flowing in at the east end. The Meoble river, which 
drains the loch, issues at the west end, and, after a course of 3 miles, 
falls into Loch Morar. There are one or two small islands at the east 
end of the loch, and one large one lying in the centre, almost equidistant 
from both ends of the loch. The length of Loch Beoraid is 3J miles, and 
its maximum breadth about one-third of a mile ; the mean breadth is 
one-sixth of a mile, and the area covered by water is 352 acres, or over 
half a square mile. The number of soundings taken was 120, the 
maximum depth obtained being 159 feet; the mean depth is over 72 
feet. The volume of water is estimated at 1,156,000,000 cubic feet, 
and the drainage area extends to 7680 acres, or nearly 12 square miles. 
There are two basins over 100 feet in depth ; one at the west end of 
the loch three-quarters of a mile in length, with a maximum breadth of 
one-sixth of a mile, approaching to within one-eighth of a mile from that 
end. The maximum depth obtained in it was 147 feet, comparatively 
very near the outflow. The eastern basin is nearly 1^ miles in length, 
with a maximum depth of 159 feet, the area over 150 feet in depth being 
almost half a mile in length. The 50-feet area is continuous from end 
to end, passing to the south of the large central island, the depth in the 
channel being 53 feet. Loch Beoraid is a rock basin divided into two 
separate basins by a rocky ridge which crosses the loch at the large 
island. At the west end of the loch there is a rocky barrier, and the 
river Meoble in its course forms a waterfall over rocks a short distance 
from its exit. The loch was surveyed on July 1, 1902. 
Temperature Observations . — The following series of temperatures 
was taken about a quarter of a mile from the west end of the loch : — 
Surface 
10 feet 
25 „ 
50 ,, 
100 „ 
140 „ 
60° 
59° 
53° 
51° 
47° 
•0 Fahr. 
•8 „ 
■9 „ 
•0 „ 
•5 „ 
48° -0 
