The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1867-06-20
ASTRONOMICAL SPECULATIOHS.


From the Washington Sunday Chronicle
BY PROF. BRAINERD, OF THE U. S. PATENT oFPIoE.
The revelations of geology show that the
earth at some period has possessed climate
essentially different from the present, and there
is reason to believe that changes of this kind are
still going on. There are evidences everywhere
an the northern hemisphere of glacial move
ments, indicating the prevalence of a tempera-
ture much below that which now prevails; and
the published account of the visit of Agassiz to
the southern hemisphere shows that the same
evidence OF glacial action exists there also.
This sdUdn intimates that these glacial move
ments are periodical and that they occur once
In about 26O,OOO years. Now, let us call to
mind that tropical plants are found in the coal
series in high northern latitudes, where 1t is
now perpetual winter, and the appearance also
OF animals of tropical haoitudes even down
rs :a late as the Tertiary period, and we have a
difficult question presented for consideration.
Hitherto, so far as know, geologists have been
unable TO give satisfactory solution to these
Phenomena, and am persuaded that they can
only De explained upon astronomical principles; (;
hypothesis which is not only sufficient to ex-
plain to any reasonable mind the geological
phenomena to which l have alluded, but also
the enigma OF glacial action, which appears to
have spread over so wide surface of the globe.
In presenting my we VS. upon this subject will
assume-brst, that body once put in lotion
will continue In that motion until arrested or
turned aside by power equal to that which put
1t in motion; that is, 1t will not change Its direc-
tion without cause. This is an unvarying law
which governs all matter. Second, that motion
thus communicated to bodies may be simple or
compound, and in either case will obey this law
of nature. Third, that the earth has three dis
tinct motions, from neither of which it will
sWerve without a sufficient cause. These mo-
tions of the earth may be defined as follows:-
The first is the diurnal or rotation upon its own
axis, and measures our days and nights; the
second, the annual or orDltal, and measures
time by completing its circle around the sun.
Both of these are so often repeated within the
ordinary period of the life of man, that we can
readily comprehend their extent and magni-
tude. The procession of the equinoxes, which
requires about 25 S6S years to complete an entire
revolution, is not in the sense we are consider
inc, proper motion OF the EARTH 1t Is rather
want of sufficient velocity to bring the earth to
the exact point in the zodiac from which 1t
proceeded the previous year, by htty and one
tenth seconds. But is there not stlll another
motion of the earth, and, if so, is there any
reason why such motion should not be continu'
Gus ? l will assume, then, that there was a
period in the history OF our planet when the
pole was at right angles to the plane of the
ecliptic. We may then ask, What would have
been the influence OF such condition on the
climate of the globe The only ans Wer that can
be given is that every portion OF its surface
would have been daily exposed to the light OF
the sun, and perpetual summer would nave
reiened over its entire surface. This condition,
or something analogous thereto, must have
been experienced during the car0oniterous
Deriod of geology; for we find the same tropical
plants wherever the coal series have been ex-
plored, whatever may be their geographical
position. And the same may pc sad OF tne 1Ie
preceding and succeeding the carbonlierous
epoch. But such condition OF things Is I'm,
possible with the pole OF the earth inclined
twenty-three degrees above the plane of the
ecliptIc We now experience perpetual winter
at the pole-that is the summer is TOO short
for the elevation of the temperature to that of
4 a tropical summer. But suppose the pole OF
and gradually change its position, SO as to APP
proach more and more nearly degree OF paral'
lelism 10 the plane OF the ecliprc, uhtll IN tne
lapse of ages it finally reached that position,
what would be the influence or such conql-
ton upon climate? But one answer can De
given: there would be but one day and one
MIC hi. during the year, and for period ans wer-
inS 10 the time of many weeks together the
north pole would be exposed to the tropical
a ravs of the sun, and at the noon OF thls SIX
month day the great lumnsry @ WoHlI oh pc yeEt,
IL would gradually recede III apparent circles
4 (yolutesl, caused by the dlurnal revolution OF
our planet, and finally sink below the equatorial
horizon. and in like manner, for the next sue
ceedine six months, illuminate the SoHthern
"A hemisphere. During the six months tropical
i dav AT the north pole, the south pole would be
involved in dreary ana Irigla higno On srS
q Ikmonths' duration, giving Use TO an enormous
n Accommodation OF snow ana ice, desuue9 10 Oe
broken up by the succeeding SIX months tIopl
zeal day. The gradual but extraordinary change
OF temperature thus eXperienced-the emerging
"Nof a hemisphere from an arctic winter OF un
= mi,ieated severity to the feryent heat OF con-
slant tropical sun, would OF necessity produce
glacial movements uIon scale OF grandeur and
magnitude of which we can form no conception
in the existing relations OF the earth 10 Tvs gIea
sonrce of light and heat, aud which have lett as
a record Of the past the most extensive eyi-
dences Of their action in former epochs upon ,1l
hoib bemispheres Aud this alienation OF siS
~ s,,.hsi dav and ak months night would con
tinne nntii this slow movement OF the earth
soain caused the sun to dip below the horizon
"a at eyeTy recurrence of its diurnal revolution
snd ~ en- would be presented the most remark
sbIe rbenomenon OF the sun rising in the wes
and setting in the east. And this is not an lm
possible Condition il the planetary relations relations
There is at least one example ol saeedi.s' dnu
traTy affection nom that OF the earth at the pre-
/ have said that this motion OF the eaTti I
J witch 1s supposed TO exist may be so slow ina
H. historic period would not be sufficient Il
marx its progress, and many no doubt Woui'