The Botany of Iceland - 01.12.1914, Blaðsíða 15

PHYSICAL GEOGRAPHY
199
the lowland which is very swainpy and above which project
numerous low, isolated, basalt hills. The eastern part is called
Borgarfjörður and the western Mýrar. From the low land several
wide valleys extend inwards between the mountains.
The north-western peninsula, • as mentioned above, constitutes
a small plateau by itself and is separated from the mainland by
Breiðifjörður and Húnaflói; the isthmus which connects the peninsula
with the mainland has a breadth of only 7 km., and rises to a height
of 228 metres. The coast of north-west Iceland, which is much in-
dented by tjords, is bounded everywhere by steep, dark mountain-
sides which often rise abruptly, even vertically, from the sea to a
height of 400—500 metres. The mountains are everywhere composed
of horizontal, or slightly inclined, tiasalt-layers which are highly
denuded by erosion, so that numerous small valleys, cirques, clefts,
ridges and Iiastions occur as in other basalt regions of Iceland. By
climbing the mountain-edge up in the highlands, and ascending to
a sufficient height it will be seen that fjords and valleys have
trenched the plateau with great regularitj7. The eye wanders freely
over wide wastes, the valleys and fjords either disappear or are
seen as insignificant clefts, and a monotonous table-Iand lies stretched
out to view, the surface of which is broken only by low ranges of
hills, and ice-striated basalt-masses with large stretches covered by
angular hlocks of rock and scattered snoW-wreaths. It is often ex-
tremely difflcult to traverse this kind of ground, across an ocean
of rocky hlocks, where the clay and the gravel between the blocks
often occur as a slushy mass owing to the thawing of the numerous
patches of snow. Only now and then can a solitary, stunted Alpine
plant he seen maintaining a miserable existence in the shelter of
the large blocks of rock. Tlie plateau of the north-western peninsula
has an average height of only about 600 metres, and where it is
highest (800--900 metres) the snow drifts and consolidates into névé-
domes — Gláma (about 60 square km.) towards the SW. and Dranga-
jökull (ahout 350 square km.) towards the NE. The numerous valleys
which lead up from the fjords and cut into this plateau are similar
in character to the other Icelandic vallevs in the basalt districts,
so it will be convenient to describe their physiographical charac-
ters collectively. Tlie bottom of the valley rises gradually in broad
rock-terraces, upon the surface of which bogs and small lakes often
occur, and it terminates amphitheatrically in a large cirque, down
the steep rocky sides of which several streams fall in cascades.