IcELAND lies just south of the Arctic circle, touching it in the
north. It is situated between lat. 68° 25' and 66° 30' north,
and long. 13° 38' and 24° 40' west. -
The shape is peculiar. It is that of an irregular ellipse, with a
considerable excrescence in the north-west, which is united to the
mainland by a neck only 4% miles across at the narrowest part.
The island is one-fifth larger than Ireland, and contains about
37,000 square miles. Its greatest length is 308 English miles,
and greatest breadth 190. It is deeply indented with fjords on
all sides except the south. It owes its upheaval entirely to
volcanic agency, and is composed exclusively of igneous rocks.
The interior of the island consists of an elevated band of
Palagonite tuff, pierced by trachyte veins; on either side of this
formation is basalt. It has been generally held that the island
was traversed by a broad trachytic valley, hemmed in between
chains of trap mountains; but this view is erroneous. Instead
of a vale, we have the great jökulls of the centre formed of tufa,
and only the fells and smaller ice-mountains on the north coast
composed of basalt,
The mountain system is in the south, and takes the shape of
* triangle, having for base a line drawn from Ok to Eyjafjalla,
*nd for apex, Thrándarjökull, which towers above the Beru-fjord.
A glance at the map would convey the idea that extensive plains
9°cupied the area of the lower portion of this triangle, but such
is not the case, The space intervening between Blà-fell, Hekla,
Tors, jökull, and the vast ice regions of Hofs and Vatnajökulls
o, in fact, occupied by ground rising gradually in rolling
heithi” sweeps, till it meets the snows of Skapta. Towards
the apex of the triangle, the glacier mountains form a compact
*** called Vatna, or Klofa jökull, covering an area of 3,500
*quare miles of unexplored snow recesses. North of this tri-
*gular mountain system is a triangular elevated plain, with the
Geographical and physical features.