Its water is quite luminous, and of great depth, especially along its northern side. It abounds in trout of a black colour and slender shape, differing much in appearance from the trout found in the limpid stream of the Avon which issues from it. At the west end of the lake is the famous Clach Dhian or Shelter Stone. This stone is an immense block of granite, which seems to have fallen from a projecting rock above it, rising to the height of several hundred feet, and forming the broad shoulder of Ben Muich Dhui. The stone rests on two other blocks imbedded in a mass of rubbish, and thus forms a cave sufficient to contain twelve or fifteen men. Here the visitor to the scenery of Loch Avon takes up his abode for the night, and makes himself as comfortable as he can where 'the Queen of the Storm sits,' and at a distance of fifteen or twenty miles from all human abode."[8] At the eastern end of the lake, we stop to take a glance at the whole scene. Right before us stands the broad top and the mural precipices of Ben Avon, severing us from the north-western world. On the right, the scarcely less craggy sides of Ben-y-Bourd and Ben Bainac wall up the waters of the lake. The other side is conspicuous by a sharp peak of Ben Muich Dhui--the same which we already mentioned as seeming to hang (and it certainly does so seem from this point) over the edge of the water. We never saw the sun shining on Loch Avon; we suspect its waters, so beautifully transparent in themselves, are seldom visited by even a midsummer gleam. Hence arises a prevailing and striking feature of the scene--the abundant snows that fill the hollows in the banks, and sometimes, even in midsummer, cover the slopes of the mountains.