8 
BATHYMETRICAL SURVEY OF 
therein being 106 feet. Towards the eastern end of the large 50-feet 
depression is a small shallow patch in the centre of the loch opposite 
Portnellan, in which a depth of 36 feet was found. 
At the extreme eastern end are situated the sluices and weir, over 
which the compensation water passes into the river Teith; at some 
distance from the sluices the depth of water flowing over a weir is 
recorded twice a day. 
The area between the shore and the 50-feet contour is estimated at 
about 635 acres, or 62 per cent, of the entire superficial area of the loch, 
while the area between the 50- and 100-feet lines is estimated at about 
324 acres, or 31 per cent., and the area with depths over 100 feet is 
estimated at about 71 acres, or 7 per cent, of the area of the loch. 
Loch Drunkie (see Plate V.). — This picturesque and irregular High- 
land loch is shut in on all sides by high hills, is difficult of access, and 
rarely visited. The surface of the loch, according to the Ordnance 
Survey maps, is 416 feet above the level of the sea, but it was raised 25 
feet in connection with the water-supply to the city of Glasgow, with 
the view of furnishing compensation water to the river Teith. The 
soundings shown on the map give the depth in the loch in April, 1899. 
Loch Drunkie is remarkable in many respects. It is the smallest 
of the five lochs in the Loch Katrine district, but deeper than the larger 
Loch Arklet situated at a similar high elevation, and quite as deep as 
the neighbouring Loch Achray situated at a lower elevation. In form^ 
it is peculiar, consisting of a quadrangular portion throwing out three 
arms of various sizes in different directions. The largest arm runs in a 
north-easterly direction, the extremity approaching within a quarter of 
a mile of the southern shores of Loch Vennachar; this arm contains 
the greatest depths observed in the loch, and^ near its extremity the 
Ordnance Survey map indicates a small island which was not seen. 
The second arm in point of size runs directly west, and contains a 
maximum depth of 80 feet. The smallest arm runs in a south-westerly 
direction, deepening gradually though irregularly from 6 feet at the 
extremity to 15 feet near the junction with the quadrangular body of 
the loch. 
The maximum length of the loch (between the extremities of the 
north-eastern and south-western arms) is over one mile ; from the 
extremity of the western arm to the opposite (eastern) shore of the loch 
is a little less. The maximum width of the quadrangular body of the 
loch is over a quarter of a mile. The mean breadth is 0*21 mile, being 
21 per cent, of the length. The waters of the loch cover an area of 
about 138 acres (0’22 square mile), and drain an area ten times greater, 
or over 1400 acres (2‘2 square miles). The number of soundings taken 
in Loch Drunkie was 155, the average depth of these being 38J feet, 
the greatest depth observed (exactly the same as in the case of Loch 
