The surface of Iceland, where free from snow, and over which men travel, may be reduced to four general formations.
1. Loose, volcanic ashey sand, grey above and black below; often mixed with pulverised Palagonite; barred with white lines of salt and potash, and either erupted subaërially or formed under water, as the rolled stones and pebbles show. This feature is found best developed in the central and the north-eastern parts of the island; the Sprengisandur and the Stórisandur (Sahará or Great Sands) being the great examples. The hills and terraces are utterly barren, because they will not hold water: the lower levels, fed by percolation, bear the normal growth, and especially the wild oat.
2. Stone; chiefly Palagonite, trap, basalts, trachyte, lavas, and obsidians, the Μαῦρα λιθάρια of the modern Greeks. It is, however, far safer travelling than the polished limestone of the Libanus, and an hour’s ride over calcareous Kasrawán is more troublesome than a day in Iceland. Its greatest inconvenience is perhaps the sun: during a clear day it becomes, in Icelandic phrase, “hot enough to make a raven gape.” A fair specimen of the stone-country may be found between Reykjavik and Krísuvík.
3. Clay and humus, the former generally disposed in horizontal strata, the latter deposited by decayed vegetation upon the surface. These formations, the Geest-lands of Denmark, mostly extend round the hill feet, dividing them from the deeper levels of bog. They form essentially “rotten” ground; drilled with holes by frost, rain, and sun, and cut by gullies of all sizes, a plexus of wrinkles or gashes and earth-cracks, radiating from the highlands to the lowlands. When the path becomes a hollow way, sunk too deep for riding, rut-tracks straggle, as in the Brazil, over wide spaces and, after the vernal thaws, the traveller will find the “corduroys” of America and the “glue-pots” of Australia; whilst in places scattered stones are so many traps for careless horses. Yet these clays and humus are the best paths and, after the sands, give the fairest chance of a gallop.
4. Bog in Iceland clothes the hill-sides, as well as the bottoms and the “flats,” that is, any low alluvial land: it is easily discovered from afar by the dull-red tint of iron-rust and the snow-white spangles of cotton-grass. There are two forms of profile: one lumpy, tussocky, and what one traveller calls “hassocky,” like the graves of a deserted churchyard; the other a plane, the swamp pure and simple; often flooded after rains, and in the dries provided with two or three veins, into which animals plunge, struggle, and fall. These channels change so frequently that none but local guides are of use, and often the best path leads to the place which has lately become the worst. Instinct and experience do something, but not much, for man and beast: both naturally prefer running water to stagnant, and when the foremost is bogged, the followers seek a better place either higher up or lower down. On frequented lines the impassable places are provided with “Brúr,” dykes or causeways of peat or stone, traversed by rude arches and flanked by shallow ditch-drains.
The Heiði, or high divide separating two river-valleys, is a “dry-land wave” (κῦμα χερσαῖον), varying from 1500 to 2000 and even 3000 feet in altitude. These ridges, especially during the mist and fog, snow and hail, wind and rain, are the horror of native travellers, and few venture upon the passage in foul weather. The profile is a harsh caricature of our Scotch and Irish moors and mosses, bogs and swamps, combining all the troubles of sand, stone, clay, and slush; whilst the marshes and drains are most troublesome to cross. “Carlines,” or old women (Vörður and Kerlingar),[81] are built in places where transit must be made at all seasons; but they are often useless, as the streams shift their bottoms, and permanent paths cannot be traced on what is neither water nor good dry land. At the beginning and end of the travelling season, snow-fonds and veins, based upon compressed ice, streak the slopes and dot the hollows, whilst natural arches and bridges, under which savage torrents gnash and foam, must be crossed on horseback. Concerning the behaviour of the snow, details will be found in the course of the Journal.
Roads are made in Iceland, like those of Syria, by taking off, not as in Europe by putting on, stones. In the more civilised parts of the island they are represented by horse-paths, which are occasionally repaired, and by sheep-paths, which are left to themselves: they humbly suggest the “buffalo” track of the prairie, and the elephant tunnel of the African forest. Not a few show worse engineering and tracery than those of olden Austria; hence we find upon the map such pleasant titles as Höfða-brekka[82] (head-brink or slope), Hálsavegr (neck-or-nothing way), Íllaklif (evil cliff), and Ófæra or Úfæra, Úfærð (the untravellable)—the latter often applied to short cuts over the sea-sands where the wayfarer is exposed to a cannonade from the heights.
§ 2. Hydrography.
The hydrography of Iceland has several peculiarities. A glance at the map shows that the Sprengisandur is the keystone of the flattened arch, which, averaging 2000 feet in altitude, forms the centre of the island. From this point the main lines diverge quaquaversally, except to the south-east, where the huge white oval, denoting the Vatnajökull, bars the way, and forms a drainage-system of its own. Hence none of the streams are navigable above the mouth, and their magnitude, as well as the dimensions of their basins, are out of all normal proportion to the area of the island. The four head rivers—Hvitá,[83] Thjorsá, Jökulsá (western), and Skjálfjandifljót (shivering or waving flood)—range from 100 to 160 miles in length. The Thjorsá is 150 miles long, and falls 2000 feet in twenty leagues, carrying more water than the Hudson of New York. “White River” is a common local name, the effect of glacier detrition giving the milky aspect familiar to every traveller in Switzerland, and hence, probably, the muddy White Nile, as opposed to the clear Blue River. A more unusual feature is the Fúli-lækr (foul or stinking stream); the iron pyrites, where the stones are ground to powder, part with their sulphur, and the latter, uniting with the hydrogen, accounts for the unsavoury name. The Jökulhlaup, or “Snow-mountain leap,” is the sudden débâcle and exundation which spring from the congealed masses, often with the irresistible might and the swift destruction of the true avalanche.
The streams in the south-eastern corner are the shortest and the most perilous, rising full grown from the glaciers, and sweeping down fragments and miniature floes of ice. Henderson is the first English traveller who forded and described the Skeiðará and the network called the Gnúpsvötn. We may here acquit him of excessive exaggeration: the natives of the eastern coast, when travelling to Reykjavik, prefer the immense round by the north to the short cut along the southern shore; and when asked the reason, they invariably allege the dangers of the snow-drains. In the course of the Journal we shall cross two of the four head streams, and observe a water-power amply sufficient for the wants of a first-rate European people. The principal cataracts are the Oxará, the Seljaland Foss, the Goða Foss, and the Dretti Foss, first visited by Baring-Gould. All have been described by travellers, and the highest is the Hengi Foss which we shall pass on the road.