ons.

The extension of these studies would furnish much of interest; but
further observations should be made upon the same animals for a
longtime continuously, relating especially to their peculiar instincts
as manifested by their various cries. We might then, by comparing and
relating acts and cries, reach the point of comprehending and perhaps
fixing the meaning in many cases where we are now in ignorance. Every
one has noticed a few facts, and has interpreted and related them, but
much is still wanting for the co-ordination of them in the point of
view of the signification of the language and communication of animals
among themselves. It has not been made in a general sense.
--_Translated for the Popular Science Monthly from the Revue
Scientifique_.

* * * * *

MODIFICATION OF OUR CLIMATE.

By JOSEPH WALLACE.

Every now and then some weather sage predicts extremely cold winters,
and another ventures to say that the sun is gradually losing heat and
in time Arctic cold will prevail over the globe. Whatever may have
been the changes during the vast cycles of time prior to the advent of
man, or whatever may be the changes in the time to come, one thing is
quite certain; that our climate has been much modified within the past
two or three thousand years.

"There have been fifteen climatic changes since the beginning of the
glacial age, each change lasting 10,500 years, and each change
reversing the season in the two hemispheres, the pole which had
enjoyed continuous summer being doomed to undergo perpetual winter for
10,500 years, and then passing to its former state for an equal term.
The physical changes upon the earth's surface during the past 80,000
years modified the changes of climate even in the Arctic regions, so
that the intense cold of the former epochs was much modified during
the latter epochs." Reckoning these climatic changes in their order,
we had entered the epoch of a more genial temperature about fifteen
hundred years ago; and if no disturbing change takes place during the
present epoch, we may reasonably expect a gradual modification of our
winters for nine thousand years to come. The changes to intense cold
from perpetual summer during the greater part of the glacial period
are supposed to have been caused by the high temperature of the north
pole as compared to that of the south pole, owing to the distribution
of land around the two, the south having almo