I may here remark that the Ódáðahraun is a desert of sand and lava, extending over an area of 1200 square miles, the greater part of which seems to have flowed from Skjaldbreið, so I think it must be one of the oldest lava flows in Iceland, for this volcano has not erupted since 1305. Some of the lava may, however, have flowed from the Dyngjufjöll, or, possibly, from fissures in the plain itself. I could, however, trace no distinct stream from the above-named mountains, nor has any one, I believe, travelled along the west side of them for the purpose of ascertaining. In several places the lava of the Ódáðahraun has run up hill. This, I believe, has been occasioned by the crust which flowed upon the surface of the lava stream, constituting a sort of pipe with the ground upon which the stream rested; and the air being thus excluded, the still liquid lava underneath has acted in the same way as water would when enclosed in a pipe, by finding its own level, or approximately so, according to its degree of fluidity. At any rate it took us five hours to cross the Ódáðahraun and reach the snow patch I had seen. There we rested, and early next morning, accompanied by Thorlákur, I set off for Skjaldbreið, leaving Eyólfur, who was very tired, in camp. We next followed an immense lava stream about half-way up the mountain, and during the early part of our walk I several times heard the muffled sound of water running beneath the lava. When about half-way up, we reached deep indurated snow, through which protruded the black hummocks and masses giving Skjaldbreið such a mottled appearance when I first saw it from the Dyngjufjöll mountains. Skjaldbreið is, however, nothing but a huge mound of basaltic lava, partially covered with snow, rising by a very gradual slope to about 4000 feet above sea level, and from it has evidently flowed the greater part of the Ódáðahraun, though, as all the neighbouring mountains seem to have erupted at some period or another, it is but fair to presume they have also helped to swell this vast wilderness of volcanic dregs; but I have been unable to trace any lava stream in the Ódáðahraun to any other source than Skjaldbreið. The summit of Skjaldbreið I found was thickly enveloped in clouds, so I stopped when within 300 feet of the top to look at the surrounding country. To our north lay the arid waste of the Ódáðahraun, the unearthly desolation of which I have never seen equalled. Truly, it may be said that it extends over but a small area when compared with many of the mighty deserts in other parts of the world, but there is a forbidding, yet fascinating grimness about this which is an especial characteristic of Icelandic scenery, and as this savage region extends as far as the eye can see, it produces none the less vivid impression upon the mind of the beholder, although one can refer to the map and find that it extends over only about 1500 square miles. When first gazing at a dreary Icelandic lava desert the sensations are something akin to those experienced when for the first time one sees a prairie immediately after the fire has swept across it; but although one is conscious that there may be a million instead of a thousand square miles of burnt, black, cindery country around, it does not impress one with its awful magnificence and grandeur of desolation as the Ódáðahraun does. To the north and east were the Dyngjufjöll mountains, with their volcanoes smoking away with renewed vigour in the cold morning air. A point further to the east was the long weary route we had just traversed, stretching away bleak and bare to where the grey pumice in the distance gave the country the appearance of lying in bright sunshine. To the south rose the Vatna Jökull, cold and gloomy, with its heights wrapped in fog and mist. Kverkfjall and Kistufell, however, were exceptionally clear; the former was smoking in three places, and a great quantity of sand and lava appeared to have proceeded from it. Between us and the Kverkfjall swept the broad tongue of glacier, reaching two-thirds of the way northward towards the Vaðalda hills, and from its extremity I counted five arms of the Jökulsá which issued from it, while the small stream from Kistufell was hidden by the intervening hills. We next continued our journey to the summit, and then found a small but perfectly formed crater, about 500 yards in circumference, but of no great depth, while in the centre rose a ridge of burnt lava, which gave the mountain the black tufted appearance I had noticed in the distance.