, Sumbava, Lombock, Java, Sumatra, the Philippines, Japan,
the Aleutian Islands, along the Rocky Mountains, Mexico, Peru, and
Chili, to Tierra del Fuego, and, in the far south, to the two great
Volcanoes of Erebus and Terror on Victoria Land.

We know that the contraction of the Earth's surface with the strains and
fractures, the compression and folds, which must inevitably result, is
still in operation, and must give rise to areas of high temperature,
and consequently to volcanoes. We must also remember that the real
mountain chains of our earth are the continents, compared to which even
the Alps and Andes are mere wrinkles. It is along the lines of the great
mountain chains, that is to say, along the main coast lines, rather than
in the centres of the continents, which may be regarded as comparatively
quiescent, that we should naturally expect to find the districts of
greatest heat, and this is perhaps why volcanoes are generally
distributed along the coast lines.

Another reason for regarding Volcanoes as local phenomena is that many
even of those comparatively near one another act quite independently.
This is so with Kilauea and Mouna Loa, both on the small island of
Hawaii.

Again, if volcanoes were in connection with a great central sea of fire,
the eruptions must follow the same laws as regulate the tides. This,
however, is not the case. There are indeed indications of the existence
of slight tides in the molten lake which underlies Vesuvius, and during
the eruption of 1865 there was increased activity twice a day, as we
should expect to find in any great fluid reservoir, but very different
indeed from what must have been the case if the mountain was in
connection with a central ocean of molten matter.

Indeed, unless the "crust" of our earth was of great thickness we should
be subject to perpetual earthquakes. No doubt these are far more
frequent than is generally supposed; indeed, with our improved
instruments it can be shown that instead of occasional vibrations, with
long intermediate periods of rest, we have in reality short intervals of
rest with long periods of vibration, or rather perhaps that the crust of
the earth is in constant tremor, with more violent oscillation from time
to time.

It appears, moreover, that earthquakes are not generally deep-seated.
The point at which the shock is vertical can be ascertained, and it is
also possible in some cases to determine the angle at which it emerges
els