The Botany of Iceland - 01.12.1914, Síða 12

196
THORODDSEN
east. ön this peninsula occur the greatest heights in northern Ice-
land (Vindheimajökull, 1445 metres; Kerling 1350 metres; Rimar,
1261 metres). Broad, fertile and thickly-inliabited main valleys stretch
up from the head of Skagafjörður and Eyjafjörður; east of Eyja-
fjörður, between the latter and Skjalfandi, the stern, wild mountains
rise to a height of 1200 metres, and there Fnjóskadalur, which cuts
through these mountains towards Eyjafjörður from the east, opens out.
These mountains fall abruptly towards the east down towards Bárðar-
dalur (70 km. long), but east of that valley the country becomes lower,
and has a different geological structure and character; hitherto,
basalt has been the dominant rock, but hereafter, for a long distance,
the substratum is formed of tuff, breccia and recent volcanic forma-
tions. East of Bárðardalur the plateau gradually sinks down to-
wards the sea, and inhabited spots occur, not only along the coast
and in the valleys, but also here and there upon the high land
itself (Myvatnssveit, 300 metres above the level of the sea; Fjallasveit,
450—500 metres). Upon these areas of the plateau there are many
isolated mountains and mountain-ridges, volcanoes and lava-streams.
The eastern part of Iceland is called collectively Austfirðir.
There the country is very mountainous towards the coast and in-
dented bj7 deep fjords which are bounded by high, precipitous rock-
walls, basalt being now again the dominant rock. From Hjeraðsflói
two long valleys, 80—90 km. in length, extend towards the south.
These valleys, which unite lower down, are called Jökuldalur and
Fljótsdalshjerað; the latter lies behind the fjord district of eastern
Iceland and cuts it otf from the interior plateau which is here
somewhat Iower than the coastal mountains, which reach a height
of 10—1100 metres and even more. Towards the south there are
two smaller Jökulls, Thrandarjökull and Hofsjökull í Lóni, with
an area of 100 and of 80 square km. and a height of 1100—1200
metres respectively. Near Hornafjörður the character of the coastal
land changes completely, because there the plateau, to its extreme
edge, is buried beneath the snow and ice-fieids of Vatnajökull. The
low, narrow and sandy coastal border is irrigated by glacier-water
streaming down from the numerous glaciers which advance through
everv cleft and valley. Here and there, along the edge of the snow-field,
mountains and rockv promontories appear, and of the former the
imposing volcano of Öræfajöknll (2119 metres), Iceland’s highest moun-
tain, is tlie most noticeable; other promontories and mountains near
the southern edge of Vatnajökull have a height of 1100—1500 metres.