170 
BATHYMETRICAL SURVEY OF 
sluice at the lower end of Loch Uidh Tarruingeach (through which the 
discharge from Loch Skinaskink passes into the river Polly) to control 
the outflow of the water, and by its means the average level of the 
loch has been raised about 3 feet. The length of Loch Skinaskink, 
measured from the south-eastern end near Lochan Gainmheich to the 
north-western arm near Loch na Moine Moire, is over 3 miles, and the 
maximum breadth is over a mile, the mean breadth being two-thirds 
of a mile. Its waters cover an area of over 2 square miles, and it 
drains directly an area of nearly 8 square miles, but since it receives 
the outflow from Lochan Gainmheich its total drainage area is over 
15J square miles — an area only times greater than the area of the 
loch. Nearly 400 soundings were taken, the maximum depth observed 
being 216 feet. The volume of water is estimated at 3,518,305,000 
cubic feet, and the mean depth at 60 J feet. Reference has been made 
to the irregularity of the floor of Loch Skinaskink, and the contour-lines 
on the map have a fanciful resemblance to an intricate maze. There 
are three main basins, which may be briefly described, viz. — (1) one 
embracing nearly the whole of the main body and surrounding Eilean 
Mor ; (2) one lying in the north-eastern arm of the loch ; and (3) one 
lying in the north-western arm of the loch. 
(1) The first basin is the largest and deepest. In it the 25-feet and 
50-feet contour-lines follow approximately the outline of the shore, 
running into all the large bays (except that the 50-feet line does not 
enter the bay south of Camas nam Fiadh). The 100-feet area has a 
very sinuous outline, almost surrounding Eilean Mor, and sending a 
large tongue into the western arm of the loch. There are two areas 
exceeding 150 feet in depth — one to the south of Eilean Mor enclosing 
the deepest part of the loch, the other to the west and north-west of 
that island extending to the north of Eilean Dubh. The 200-feet area 
is small, based on soundings of 204 and 216 feet, the last-mentioned — 
the deepest sounding in the loch — lying about 350 yards to the south of 
Eilean Mor. The great feature, of this basin is the occurrence of two 
/ hills to the west of Eilean Mor ; the one nearest the island is covered by 
38 feet of water, the depth between it and the island being 70 feet, 
and between it and the south-western shore exceeding 100 feet; the 
other is covered by 41 feet of water, the depth around it being from 
100 to 150 feet. 
(2) The second basin in the north-eastern arm is much smaller, and 
the 25-feet and 50-feet contour-lines are continuous with those of the 
preceding basin. The 100-feet area is centrally placed in this arm, and 
has a maximum depth of 137 feet. A small isolated 25-feet area lies to 
the north-west of Eilean Dubh in this arm, with a maximum depth of 
34 feet. 
(3) The third basin in the north-western arm is the smallest and 
shallowest of the three, and is cut off from the main basin by very 
