certainly active.[11] They are not so high as those of Kamtschatka; but,
on the other hand, they rise from very deep oceanic waters, and have
been probably built up from the sea bottom by successive eruptions of
tuff, lava, and ash. According to the view of Professor Milne, the
volcanoes of the Kurile chain are fast becoming extinct.

(_f._) _Volcanic Groups._--Besides the volcanic vents arranged in lines,
of which we have treated above, there are a large number, both active
and extinct, which appear to be disposed in groups, or sporadically
distributed, over various portions of the earth's surface. I say _appear
to be_, because this sporadic distribution may really be resolvable (at
least in some cases) into linear distribution for short distances. Thus
the Neapolitan Group, which might at first sight seem to be arranged
round Vesuvius as a centre, really resolves itself into a line of active
and extinct vents of eruption, ranging across Italy from the Tyrrhenian
Sea to the Adriatic, through Ischia, Procida, Monte Nuovo and the
Phlegraean Fields, Vesuvius, and Mount Vultur.[12] Again, the extinct
volcanoes of Central France, which appear to form an isolated group,
indicate, when viewed in detail, a linear arrangement ranging from north
to south.[13] Another region over which extinct craters are distributed
lies along the banks of the Rhine, above Bonn and the Moselle; a fourth
in Hungary; a fifth in Asia Minor and Northern Palestine; and a sixth in
Central Asia around Lake Balkash. These are all continental, and the
linear distribution is not apparent.

[1] For an interesting account of this range of volcanic islands see
Kingsley's _At Last_. The grandest volcanic peak is that of Guadeloupe,
rising to a height of 5000 feet above the ocean, amidst a group of
fourteen extinct craters. But the most active vent of the range is the
Souffriere of St. Vincent. In the eruption of 1812 this mountain sent
forth clouds of pumice, scoriae and ashes, some of which were carried by
an upper counter current to Barbados, one hundred miles to the eastward,
covering the surface with volcanic dust to a depth of several inches.

[2] An excellent, and perhaps the most recent, map of this kind is that
given by Professor Prestwich in his _Geology_, vol. i. p. 216. One on a
larger scale is that by Keith Johnston in his _Physical Atlas_.

[3] _Memoir on the Physical Geology and Geography of Arabia Petraea,
Palestine_, etc., published for th