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 150 ICELAND side. This basalt, the oldest formation, under- lies the other two, the palagonite, which is next in age, and the lava, comprising all the strata due to recent volcanic action. Although the N". W. peninsula is composed of lofty ridges with here and there an extinct volcano, the chief mountain system is in the south. It forms a triangular mass, with its apex at Thrandar Jokull in the east, and its base ex- tending from Ok in the west to Eyjafjalla in the south. Toward the apex the great Vatna Jokull group covers an area of 3,500 sq. m. with its gigantic glaciers and snow fields. The mountains are distinguished into fells, which are generally free from snow in summer, and jokulls or ice mountains, which are shrouded in perpetual snow. The name of skal is given to perfectly symmetrical mountains. The prin- cipal jokulls are the Oreefa, 6,405 ft., the east- ern Snsefell, 5,958 ft., and the western Snasfell, 4,699 ft. The volcanoes belong to all three classes. Beyond the mountain masses lies the great central table land, from 1,500 to 2,000 ft. above the sea, and forming a wilderness covered with vast lava beds, barren heights or rolling rocky uplands, tracts of black volcanic sand, hillsides and valleys dotted with hot springs and sulfataras, and bottom lands filled with bog and mud. Over this desert three main roads, or rather tracks, connect the set- tlements near the fiords and the rare low plains and valleys extending inland along the water- courses. The most remarkable and fertile val- leys are those clustering around Eyjafiord in the north, that of Lagarfljot in the east, and those of the Hvita and Thjorsa in the south. Volcanic action has manifested itself over a broad belt of country, extending from Cape Reykjanes in the southwest to Krafla in the north. Within this belt are the principal vol- canoes, including Hecla. (See HEOLA.) From 27 different spots, counting volcanic craters in the sea off Cape Reykjanes, 86 eruptions have occurred since 874, the last being those of Skapta in 1861 and of Trolladyn-gja in 1862. The lava has been thrown out from grassy plains in the north as well as from the enor- mous double chasm of Katla in the south- ern uplands. Of the lava beds, the Odatha Ilraun covers 1,160 sq. m., a second extends 73 m. from Skjaldbreith and Klothufell to Reykjanes, and a third, around Hecla, is 25 m. long and 10 m. broad. Another peculiarity is what is called the gjd or rifts in the deep lava beds, which are zigzag rents running from northeast to southwest. The most remarkable are the Almanna-gja and Hrafna-gja at Thing- vellir, and the rift into which pours the Joknlsa at Dettifoss. The principal lakes in Iceland are the Myvatn (Midge lake) in the north, much diminished in depth and extent by the lava streams from Krafla in 1724-'30, and Thing- vallavatn in the southwest, 10 m. long by 4 wide. There are besides two principal groups of lakes, those of the Arnarvatn (Eagle tarns) dotting a large district N. and W. of Eyriks Jokull, and Fiskivatn (Fish tarns) at the foot of Skapta, which are the remains of a large lake that existed previous to the eruption of 1783. The larger rivers take their rise in the southern mountains. The Jokulsa, reputed the largest, rises at the foot of Vatna, and flows N. to the Axafiord. About 30 m. from the sea it falls over a perpendicular wall in its lava bed, forming a magnificent waterfall. The Skjal- fandafljot has its source between Vatna and Ar- nasfell, and flows N. into Skjalfandi bay. The Jokuldalsa and the Lagarfljot flow N. E. from the snow fields of Vatna. The most impor- tant rivers in the west and south are the Hvita (or, as it is called near its mouth, the Olfusa), Thjorsa, and Kudafljot. The most celebrated feature of Iceland scenery is the great number of intermittent hot springs, chiefly in the S. W. division, which have given the name of geysers to similar springs elsewhere. (See GEYSERS.) The climate of Iceland seems to have changed greatly since its first settlement. The ice drifts from Greenland, which formerly visited its shores only every other year, have of late come for 15 years in succession, surrounding two thirds of the island with a compact mass, and remaining from three to five months. When it comes in January or February, it goes away in March or April ; then it affects the ensuing vege- tation but little, while it brings a welcome sup- ply of whales. If it comes in April or May, it remains until the end of July, stopping vegeta- tion and destroying all the crops. The average winter temperature at Reykiavik, 29'3 F., is higher than at Aberdeen, 26 F. ; the average summer temperature is 53'6, and that of the whole year 39-4, being about the same as that of Moscow the whole year round. At Aku- reyri, in the north, the average summer heat is 45'5, that of winter 20'7, and the mean for the year is 32. The difference of climate be- tween the north and south of the island is at- tributed to the Gulf stream, which sweeps round the 8. and S. W. coasts. In the south great quantities of rain fall in winter and sum- mer, and sharp winds are frequent; thunder, except in winter, is very seldom heard. The climate of the north is much more dry and regular. The lowlands and protected valleys afford excellent pasturage, where the soil con- tains all the elements of fertility. " The moun- tains," says Baring-Gould, "are generally des- titute of herbage, and the valleys are filled with cold morasses. Grass springs on the slight elevations above the swamps, in the dells, and around the lakes. By drainage a large percentage of marsh might be reclaimed ; but some must always remain hopeless bog. The extraordinary amount of swamp is due to the fact that the ground is frozen at the depth of 6 or 8 ft., so that when there is a thaw the valleys are flooded, and the water, unable to drain through, rots the soil." Many bottoms are filled with an amazing depth of rich soil, yet the prevalent ignorance of agricultural methods prevents their being turned to any ad-