. Calogero, about four miles from the town of Lipari.
Daubeny considers it not improbable that this island may have had an
active volcano even within the historical period, a view which is borne
out by the statement of Strabo.[2]

[Illustration: Fig. 12.--Island of Vulcano, one of the Lipari Group, in
eruption.--(After Sir W. Hamilton.)]

(_b._) But by far the most remarkable island of the group, as regards
its present volcanic condition, is Stromboli, which has ever been in
active eruption from the commencement of history down to the present
day. Professor Judd, who visited this island in 1874, and has produced a
striking representation of its aspect,[3] gives an account of which I
shall here avail myself.[4] The island is of rudely circular outline,
and rises into a cone, the summit of which is 3090 feet above the level
of the Mediterranean. From a point on the side of the mountain masses of
vapour are seen to issue, and these unite to form a cloud over the
summit; the outline of this vapour-cloud varying continually according
to the hygrometric state of the atmosphere, and the direction and force
of the wind. At the time of Professor Judd's visit, the vapour-cloud
was spread in a great horizontal stratum overshadowing the whole island;
but it was clearly seen to be made up of a number of globular masses,
each of which is a product of a distinct outburst of volcanic forces.
Viewed at night-time, Stromboli presents a far more striking and
singular spectacle. When watched from the deck of a vessel, a glow of
red light is seen to make its appearance from time to time above the
summit of the mountain; it may be observed to increase gradually in
intensity, and then as gradually to die away. After a short interval the
same appearances are repeated, and this goes on till the increasing
light of dawn causes the phenomenon to be no longer visible. The
resemblance presented by Stromboli to a "flashing light" on a most
gigantic scale is very striking, and the mountain has long been known as
"the lighthouse of the Mediterranean."

The mountain is built up of ashes, slag, and scoriae, to a height of (as
already stated) over 3000 feet above the surface of the sea; but, as
Professor Judd observes, this by no means gives a just idea of its vast
bulk. Soundings in the sea surrounding the island show that the bottom
gradually shelves around the shores to a depth of nearly 600 fathoms, so
that Stromboli is a great conical mass of cind