Iceland is a fifth part larger than Ireland, and its superficial area is estimated at 39,207 square miles. Not more than 4000 miles, however, are habitable, all the rest being ice and lava; for the island seems to be little more than a mass of trachyte, snow-shrouded and frost-bound, resting on a sea of fire. It consists of two vast parallel table-lands, the foundations of ranges of lofty mountains, most of which are active volcanoes; and these table-lands strike across the centre of the island, from north-east to south-west, at a distance from one another of ninety to one hundred miles. Their mountainous summits are not pyramidal, as is generally the case in Europe, but rounded like domes, as in the Andes of South America. Their sides, however, are broken up by precipitous masses of tufa and conglomerate, intersected by deep ravines of the gloomiest character. They are covered with a thick shroud of ice and snow, but in their wombs seethe the fiery elements which ever and anon break forth into terrible activity. The eastern table-land and its mountain range is the most extensive, and contains Oërafa, the culminating point of Iceland. It is visible from a great distance at sea, like a white cloud suspended above the island. Its height is 6426 feet, and it springs from a vast mountain-mass; no fewer than 3000 square miles being perpetually burdened with ice and snow, at an altitude varying from 3000 to 6000 feet. [Illustration: AN ICELANDIC LANDSCAPE.] A very considerable portion of the island is occupied by the large glaciers which descend from the mountains, like frozen torrents, pushing forward into the lowlands, and even to the margin of the sea. These act as almost impassable barriers to communication between the various inhabited districts. We have spoken of the two ranges of table-lands as about ninety to one hundred miles apart. The interspace forms a low broad valley, which opens at either extremity on the sea--an awful waste, a region of desolation, where man is utterly powerless; where the elements of fire and frost maintain a perpetual antagonism; where blade of grass is never seen, nor drop of water; where bird never wings its way, and no sign of life can be detected. It seems a realization of Dante’s “circle of ice” in the “Inferno.” The surface consists of lava streams, fissured by innumerable crevices; of rocks piled on rocks; of dreary glaciers, relieved by low volcanic cones. It is supposed that some remote portions of the inaccessible interior are less barren, because herds of reindeer have been seen feeding on the Iceland moss that fringes the borders of this dreary region. But there is no reason to believe that it can ever be inhabited by man. [Illustration: MOUNT HEKLA, FROM THE VALLEY OF HEVITA.]