New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1904-04-07

irregularities which sometimes show disposi-
ton 10 far into cycles. says that hasty conclu-
eions have been drawn therefrom. but does not
think the supposed changes we'll established as
vet. or the slow. oscillations that have received
the most attention. that running parallel with
the eleven year sunspot period is the first one
mentioned The Austrian cites some Of the
Alterations Of Konppen. Medium and Lockyer
REGARDING II. hut concludes that most Of the evil
een-e which had come to him IS still too I'M
certain 20 show any actual relation between
cause and effect" AS most of Bigelow's work
has been done since that opinion was expressed
the comment can hardly apply thereto. Bruck-
ner's observations, tending 10 show that there Is
2 cycle In temperature and rainfall thirty-five
years long. are viewed with favor. DR.. Ham
thinks that he has demonstrated the existence
Ct the period with high degree Of probability.
That other climatic changes. far more extreme
in degree and stretching through vastly longer
periods have really occurred on the globe is be-
yond question Geology shows that in the Ter
tiary age vegetation such as IS now found only
in temperate ATTITUDES floUrished in the northern
part Of Alaska and Greenland and IN Spitzbergen
Later a vast ice sheet from the Arctic reached
away down in North America TO the Ohio River
and the south shore Of Long Island. large
part Of Northern Europe was similarly covered.
The SNOW line of the Alps more than four
thousand feet lower than now. Concerning the
causes Of the glacial period. which is now be-
lieved to have been a series OF Intermittent Vsl-
tations. there has been vast amount OF in
eenioYs speculation. Practically all OF the more
striking hypothesis advanced to account for
these changes are astronomical. DIT. Ham re-
views several Of the most important. He re-
Trains from discussing the theory OF Dubois.
based on the probable fluctuations in the suns
thermal output but mentions the differences
which have been drawn from The changes in
the inclination of the earth's axis 10 the ecptic
in the ecceutricity Of its orbit and the unequal
length Of the seasons.
The EARTH il viii be remembered. is some
three million miles nearer 10 the sun at one
point in its orbit than the opposite side.
just now it IS there-at Notwithstanding the
winter OF the northern hemisphere. The cold
Of that season results from the fact that the
North Pole IS tilted away from the sun. If.
however. our winter came when the earth was
at the greatest distance-at apheliOn-the sea-
would be much more severe. as well
longer. Owing 10 well known causes the posi-
ton Of the globe is slowly shifting so that it
works its way half way around the circle in
1880 years, and gets back TO the starting
point in 21.O90. Adh6mar thought that sue
cession OF aphelon winters would create such
81 accumulation Of ice near the pole as TO shift
the earth's centre Of gravity. and lead to such
a flow Of water thither as to food the con-
tin1nts partially. Schmck assumed that the
latter effect might also result from an enhanced
influence Of the sun the tides. DIT. Ham
shows how little valid reason there is for &C
ceptinE either OF these notions.
Crou started with the same premises. but i'm
proved on the suggestions Of his predecessors.
The most novel feature Of his theory was that
during the long series Of years in which the
earth had apheon winters the force OF the
northern trade winds would be increased. a