40 BATHYMETRICAL SURVEY OF 



LOCHS OF THE GRUINARD BASIN. 



WITHIN this basin eight lochs were sounded by the Lake Survey, viz. 

 Lochs na Sheallag, Fionn, Dubh, Beannach, na Moine Buige, Eileach 

 Mhic'ille Eiabhaich, Fada, and na Beiste. The drainage basin under 

 consideration (see Index Map, Fig. 3) extends from the mouth of Gruinard 

 bay (between Stattic Point on the east and Creag an Eilean on the west) 

 to the heights of Beinn Tarsuinn, Mullach Coire Mhic Fhearchair, and 

 Beinn Bheag, and includes numerous small lochs which could not be 

 surveyed for lack of boats. As measured by the planimeter on the 1-inch 

 Ordnance Survey maps the total area of this basin is about 117 square 

 miles, of which considerably more than one-half, or over 66^ square miles, 

 drain into the lochs under consideration, as will be seen in the summary 

 table. Loch na Sheallag flows directly into Gruinard bay by the river 

 Gruinard, as does Loch Fada by the Allt Bad an Luig, and Loch na 

 Beiste by the Allt Udrigill, while the remaining lochs mentioned form 

 a connected series, whose waters are carried into Gruinard bay by the 

 Little Gruinard river, Loch Dubh adjoining the head of Loch Fionn, 

 Lochan Beannach flowing into Loch Fionn about midway down the western 

 shore, Loch na Moine Buige flowing in at the head of Loch Fionn, while 

 Loch Eileach Mhic'ille Riabhaich carries the outflow from Loch Fionn 

 into the Little Gruinard river. 



Loch na Sheallag (see Plate XVI.). Loch na Sheallag is situated 

 about 9 miles to the north-east of Loch Maree, amid wild and magni- 

 ficent scenery, the head of the loch lying between the heights of An 

 Teallach (Bidein a' Ghlas Thuill 3483 feet, and Sgiirr Fiona 3474 

 feet) on the north-east, and of Beinn Dearg 2974 feet on the south- 

 west. It contains salmon, sea trout, river trout, and char, but the fishing 

 is preserved. The loch trends in a south-east and north-west direction, 

 and is 3| miles in length. It is broadest towards the south-eastern 

 (inflow) end, where the maximum width of over two-thirds of a mile 

 occurs, narrowing gradually towards the outflow end. Its waters cover 

 an area of about 876 acres, or over 1^ square miles, and it drains an area 

 27 times greater an area of about 37 square miles. The maximum depth 

 of 217 feet was observed in the wider part of the loch, about a mile from 

 the south-east end. The volume of water is estimated at 3948 millions 



