THE FRESH- WATER LOCHS OF SCOTLAND. 45 



than 50 yards across, and, if it were pierced through, the promontory 

 wonld become a central island, entirely surrounded by the waters of the 

 loch. Lochan Beannach is about two-thirds of a mile in length by one- 

 third of a mile in maximum breadth, covering an area of about 80 acres, 

 and draining an area of over 4J square miles. The maximum depth of 

 27 feet was observed in the southern portion of the loch, comparatively 

 close to the' largest island. The volume of water is estimated at 22 

 million cubic feet, and the mean depth at 6| feet. The floor of Lochan 

 Beannach is irregular, with many islands and rocks rising above the 

 surface of the water. The deepest sounding (27 feet), and a neighbouring 

 one of 23 feet, were the only ones exceeding 20 feet in depth, while 

 a sounding of 18 feet was taken in the northern part of the loch, and two 

 of 14 feet off the north-eastern shore, the area covered by less than 10 feet 

 of water being about 70 acres, or 88 J- per cent, of the total area. 



Loch no JIbine Buige (see Plate XVII.). Loch na Moine Buige is 

 a small loch lying at the foot of the Fionn Loch, into which it drains by a 

 short stream. It trends north-west and south-east, and is about three- 

 quarters of a mile in length, with a maximum breadth of less than a 

 quarter of a mile, covering an area of about 55 acres. The maximum 

 depth of GO feet was observed close to the shore near the south-eastern 

 end, where the stream flows out of the loch. The volume of water is 

 estimated at 59 million cubic feet, and the mean depth at over 24J feet. 

 The variation in the level of the water is slight, the highest drift-mark 

 observed being only half a foot above the water on the date of the survey 

 (August 8, 1902), when the loch was at its lowest level. Loch na Moine 

 Buige is comparatively deep, considering its dimensions, the 25-feet area 

 extending nearly from end to end, and covering nearly one-half of the 

 total area of the loch. The 50-feet area is very small, based on the single 

 sounding of 60 feet close to the south-western shore, so that the slope 

 of the bottom in that position must be steep. The area covered by less 

 than 25 feet of water is about 29 acres, or 52 per cent, of the entire area. 



Loch Eileach Mhic 'ille Riabhaich (see Plate XVII.). This little loch 

 is merely a deepening and widening of the river flowing out of the Fionn 

 Loch, from which it is separated by two waterfalls ; at its outflow is a 

 third waterfall, separating it from another smaller expansion of the Little 

 Gruinard river. It trends north-north-east and south-south-west, and 

 is nearly three-quarters of a mile in length, with a maximum breadth 

 of less than a quarter of a mile, covering an area of about 30 acres. It 

 drains directly an area of about half a square mile, but, since it carries the 

 outflow from the Fionn Loch, its total drainage area is over 27 square 

 miles an area nearly 550 times greater than that of the loch. The 

 maximum depth of 33 feet was observed in the wide part near the foot 

 of the loch, where there is a small circular area exceeding 25 feet in 



