er this eruption, we shall find its farmers risking
again the chance of its uncertain temper. But this is not the case with
the land covered with lava and cinders. Time for their disintegration
is necessary before they can be brought under cultivation, and this is
a matter of years. After the great eruption of 1871-72 the land covered
with cinders did not bear crops for seven years, and there is no reason
that they will do so sooner on the present occasion. So for years to
come much of the volcanic soil must remain a barren and desert void.

CHAPTER XVI.

The Great Lisbon and Calabrian Earthquakes.

To our account of the great earth convulsions of San Francisco it is in
place to append a description of some similar events of older date. It
is due to the same causes, whatever these causes may be, the imprisoned
forces within the earth acting over great distances during the
earthquake, while they are concentrated within some limited space when
the volcano begins its work. The earthquake is the most terrible to
mankind of all the natural agencies of destruction. While the volcano
usually has a greater permanent effect upon surface conditions, it is,
as a rule, much less destructive to human life, the earthquake often
shaking down cities and burying all their inhabitants in one common
grave. Violent earthquakes are also of far more frequent occurrence than
destructive volcanic eruptions, many hundreds of them having taken place
during the historic period.

While the earthquake is only indirectly connected with the subject of
our work, it seems desirable to make some mention of it here, at least
so far as relates to those terrible convulsions whose destructiveness
has given them special prominence in the history of great disasters.
Ancient notable examples are those which threw down the famous Colossus
of Rhodes and the Pharos of Alexandria. The city of Antioch was a
terrible sufferer from this affliction, it having been devastated some
time before the Christian era, while in the year 859 more than 15,000
of its houses were destroyed. Of countries subject to earthquakes, Japan
has been an especial sufferer, in some cases mountains or islands being
elevated in association with shocks; in others, great tracts of land
being swallowed up by the sea. The number of deaths in some of these
instances was enormous.

Numerous thrilling examples of the destructive work of the earthquake
at various periods are on record. Of t