CHAPTER I.

DORMANT VOLCANOES OF PALESTINE AND ARABIA.

(_a._) _Region east of the Jordan and Dead Sea._--The remarkable line of
country lying along the valley of the Jordan, and extending into the
great Arabian Desert, has been the seat of extensive volcanic action in
prehistoric times. The specially volcanic region seems to be bounded by
the depression of the Jordan, the Dead Sea, and the Arabah as far south
as the Gulf of Akabah; for, although Safed, lying at the head of the Sea
of Galilee on the west of the Jordan valley, is built on a basaltic
sheet, and is in proximity to an extinct crater, its position is
exceptional to the general arrangement of the volcanic products which
may be traced at intervals from the base of Hermon into Central Arabia,
a distance of about 1000 miles.[1]

The tract referred to has been described at intervals by several
authors, of whom G. Schumacher,[2] L. Lartet,[3] Canon Tristram,[4] M.
Niebuhr,[5] and C. M. Doughty[6] may be specially mentioned in this
connection.

The most extensive manifestations of volcanic energy throughout this
long tract of country appear to be concentrated at its extreme limits.
At the northern extremity the generally wild and rugged tract of the
Jaulan and Hauran, called in the Bible _Trachonitis_, and still farther
to the eastward the plateau of the Lejah, with its row of volcanic peaks
sloping down to the vast level of Bashan, is covered throughout nearly
its whole extent by great sheets of basaltic lava, above which rise at
intervals, and in very perfect form, the old crater-cones of eruption. A
similar group of extinct craters with lava-flows has been described and
figured by a recent traveller, Mr. C. M. Doughty, in parts of Central
Arabia. The general resemblance of these Arabian volcanoes to those of
the Jaulan is unquestionable; and as they are connected with each other
by sheets of basaltic lava at intervals throughout the land of Moab, it
is tolerably certain that the volcanoes lying at either end of the chain
belong to one system, and were contemporaneously in a state of activity.

(_b._) _Geological Conditions._--Before entering any further into
particulars regarding the volcanic phenomena of this region, it may be
desirable to give a short account of its geological structure, and the
physical conditions amongst which the igneous eruptions were developed.

Down to the close of the Eocene period the whole region now under
consideratio