1847, both inclusive), the number of earthquakes
near new and full moon exceeded the
number at the quarters, in the proportion of six
to five. Further observations seemed to
confirm this curious deduction, but at present it
can only be regarded as suggesting future
inquiry. It certainly seems to be the result of
all observations lately made, that there is some
relation between the moon's place and the
convulsive paroxysms of the earth.

Out of 5879 earthquakes that have occurred
in the northern hemisphere, and of which the
exact dates are recorded, as many as 3158 took
place in the cold months between the 1st of
October and the 31st of March: only 2721 being
felt between the 1st of April and the 30th of
September. The largest number—627—occurred
in January, and the smallest—415—in July.

Turn these unexpected figures as we will,
they seem always to point in the same direction,
and to intimate that, in all countries liable to
change of seasons, the warm season is less
subject to earthquakes than the cold.

Thus, if we take all Europe together, we find
1153 recorded in the cold, and only 857 in the
warm months. If we take the countries separately,
the British Islands list shows 94 in the summer,
and 123 in the winter. Spain and Portugal, 87
in summer, and 114 in winter. Italy gives the
numbers 455 and 438; France, Belgium, and
Holland together, 272 and 395 in the warm
and cold months respectively.

There is another curious result obtained on
comparing the number of earthquakes in different
seasons. During the two months that enclose the
four critical periods of the year, called by
astronomers the equinoxes and the solstices,
earthquakes seem more likely to happen than during
the intermediate months. Thus, in December
and January, in the winter solstice, the number
is 177; in March and April, the vernal or spring
equinox, 151; in June and July, the summer
solstice, 129; and in September and October,
the autumnal equinox, 164. There are only about
290 earthquakes left for the other four months.
This average was obtained from the details of
the earthquakes during the first forty-three
years of the present century.

On tracing back the accounts of these
remarkable phenomena, we shall find that though
evidently convulsive and paroxysmal, and following
no regular law yet determined, they still
show certain general relations worth considering.
Thus, small earthquakes often recur after short
intervals, but between sets of them thus
frequently repeated in any one district there are
intervals of comparative repose. The smallest
of such intervals is not more than a year or two.
These small intervals correspond to periods
when there are on the whole fewest earthquakes;
and generally, but not always, such earthquakes
have not been of the most destructive kind. On
the other hand, the average interval is five to
ten years, and the earthquakes that then occur
are more serious and more numerous.

Two marked periods of extreme paroxysm, or
greatest earthquake intensity, seem to occur in
each century: or at least this has been the case
for some centuries past. One of these periods
is greater than the other, and has occurred near
the middle of the century. The other, very
serious but not of equal importance, towards the
close of the century. It is worthy of notice that
two or three great and destructive earthquakes
have often happened within a few years in very
distant parts of the world at these periods.

It would seem that whatever be the cause of
earthquake paroxysms, this cause requires a
certain time to recover its energy after having
exhausted itself by a great struggle. Smaller
movements, from time to time, also convulsive,
produce comparatively little effect beyond the
alarm consequent on local disturbances.

Some of the great earthquakes mentioned in
modern history, and the subject of special
description, have occurred with remarkable
regularity at about the intervals of time mentioned
above, but they have affected parts of the world
very distant from each other, and without any
apparent mutual relations. If, however, we
regard the tract including the north of Africa, the
whole of Europe, Northern Asia, the North
Atlantic Ocean, the North American shores of
the Atlantic, and the West Indian Islands, as
being that which most interests us, we shall find
that during the latter part of the sixteenth
century there were numerous and very severe
disturbances, accompanied by remarkable
appearances of aurora borealis in low latitudes.
These earthquakes extended throughout Central
Europe, being felt, indeed, from Northern Asia
to the Atlantic, including our own islands. They
were accompanied by disastrous inundations
arising from the great rivers as well as the sea.
The shocks felt in London at this time have
been already alluded to.

In 1626, occurred one of the most fatal of the
South Italian earthquakes, by which more than
thirty towns and villages were destroyed, and
seventeen thousand persons lost their lives. The
disturbances continued until 1631, terminating
by a great eruption of Vesuvius. In 1657, great
earthquakes occurred in Scandinavia, and shortly
afterwards in Calabria, the Pyrenees, and Central
Italy, and these were felt also in England.
Towards the end of the same century there are
many remarkable disturbances recorded, including
that of Jamaica. In 1755 was the great earthquake
of Lisbon, preceded by numerous smaller
convulsions all over Western Europe, and
followed by others of great significance. Later in
the century (in 1770), were fearful earthquakes
in the West Indies, and afterwards again in Calabria.
The century closed with a severe convulsion
over the whole of the north-west of France, and
many shocks in Scandinavia and Russia. During
the present century, there have been many not
unimportant disturbances of this kind over the
whole of Europe and Northern Asia—more, in
fact, than would easily be credited, if we had not
the record before us. Perhaps the frequency of
shocks has prevented the accumulation of force
which terminates in one grand convulsion.

Although, however, it really appears to have