New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1902-06-30
SOME LESSONS or THE cAoUDs.


Straws show which way the wind blows. and
so do the clouds. But as clouds float at much
greater elevations than straws they supply
much more information. To the practical
meteorologist the direction and velocity of the
wind are of Importance in forecasting To the
theoretical meteorologist, who has YET much to
learn about the motions of the air. they are
likely to reveal facts hitherto unsupported. In
the latest number of The Monthly Weather Re
view" for instance, Professor Frank H. Bige-
low presents some new ideas concerning the
circulation Of the atmosphere which are based
recent studies of the clouds under the au-
spices of the United States Weather Bureau.
Something like twenty-five thousand dbserva-
tons were made with nepheloscopes, ami these
were supplemented by six thousand olserva-
tons Nth surveying instruments 10 diets line
heights. This work was conducted otAi an
area that embraced a part of Canada n We'll
as the United States. and extended froA lthe
Rockies to the Atlantic. One complete year
was devoted to making the record so as TO cor
rect seasonal deviatons; both high and low
pressure areas were scrutinized, and the clouds
were observed up to height of over six miles,
below which level lies more than two-thirds of
the whole quantity of the atmosphere The
data appear to be ample enough, therefore. to
Justify certain conclusions
The most novel of the opinions which Pro
fessor Bigeow is thus led to adopt is that the
late William Ferrel'S conceptions of the inter
change of air between the equator and the
poles were not altogether correct Ferrel
thought that there was a generally nOrthward
movement at very great elevations and 4
southwark movement down near the earth. In
other words he believed that the equatorial
and polar currents flowed at different levels.
When Professor Bigeow comes to sum I'D the
motions Of all the clouds included in the survey
under discussion, he finds that there is "A sys-
tematic eastward flow, whose velocity steadily
increases with altitude, but that height has
practically nothing to do with motion Mt right
angles thereto. At each of half a dozen planes
between the earth's surface and the six mile
limit the northward drift is almost exactly
compensated by the southwark drift There
is, to be sure, slight preponderance of north
ward motion, but this is nearly uniform for all
levels. So far as the area included in this study
is concerned, therefore, the interchange of
arctic and tropical air Is apparently accom-
plished by currents moving side by side but
both exhibiting the greatest force at the height
of about two miles. Until these indications are
corroborated by observations all the wav arouno
the globe in the same latitude they will NOT he
conclusive. Professionally, though strong case
is made out
Professor Bigelow arrays himself against an
other theory which has been widely held Espy,
Ferret and other authorities have taught that
the immediate cause Of barometric depres-
sion and the spiral inflow of winds thereto was
local heating, which gave rise to an ascensionaI
movement and a sort of suction. In other
words the force which set the winds in motion
operated from within the storm area Bieelow
follows Ham, the Austrian meteOroloeist I'm