The sun. [volume] (New York [N.Y.]) 1833-1916, 1888-01-15

though Of course Of different origin, OF the
great undulations OF tho air that were caused
By the tremendous volcanic explosion on the
island OF Krakatoa In 1883, and which. three
times in succession. encircled tho whole Garth.
The other interesting point to which we re-
ferred Is Mr.. Abercromby's remarks about dif.
ference Of kind In rain and wind. Cyclone
rain, he says, differs from non -isobaric rain. or
the rain In q wedge. one characteristic OF cy-
clone rain being that It appears Ito grow out
OF tho mir" owing to the dampness that marks
the front Of a%cyclone.
SO winds differ. All tho world knows that
chimneys smoke more with an east wind than
with q west one. The explanation suggested
is that the winds may not blow horizontally.
the east wind being directed downward.
The concluding chapters OF his book are do.
voted to showing what can be and should be
accomplished. both by solitary observers and
by those who can command the materials for
making syroptic charts In forecasting the
weather. Summaries OF tho results obtained
BY the meteorological service OF Great Britain.
the United States. Canada, and Germany, show
that the universal Yankee is slightly ahead.
In regard to the much-talked-of question OF
the possibility Of Forwarding Europe Of the
approach OF q cyclone crossing the Atlantic,
Mr.. Abercromby concludes that from the ma
ture OF cyclone motion the idea can never be
used in practical foreoasttng." From oight to
twenty cyclones. however. do cross the Allan
tic from shore to shore In . year. Our author
gives q chart showing the paths OF some OF
them. One Is Of particular interest. for having
started west OF our great lakes It crossed the
ocean, swept over the British Islands, pursued
a serpentine course over the German Ocean
and the Scandinavian peninsula, then dipped
southwark half way across Europe, and turn
ing northward again finally disappeared In the
gloomy wastes OF Siberia. Its whole recorded
history lasted twenty days, Of which eight were
consumed in crossing the ocean from Nova
Scotia to Ireland. This remarkable cyclone
occurred in July. 1879. Its history is q good OK
ample Of the variable nature Of a cyclone. Not
only was its course erratic and its rate of
travel very unequal. but its intensity and size
varied. Some days tho wind blew q gale. at
other times its barometrio slopes were SO gem
tie as only to develop q breeze.
".
And now. finally. recurring to the imaginary
picture Of the globe with its atmosphere, with
which we began. let US see what new features
We must introduce. and whatthe general effect
will be when, to the great currents that arise
from the inequality of heat between the poles
She Az o'iuotoi uhu vi tuo a III . EOt0llOus
We add the influence OF the various isobario
forms described in Mr.. Abercromby's book. It
Is evident at a glance that cyclones, anti
cyclones, &C.. may be likened to eddtes, ripples,
whirls. and backwaters In the general dow Of
the atmosphere. A cyclone resembles an eddy
that draws the air upward: an anti.oyclone an
eddy that draws the air downward. This dii-
ference Of motion. 1t can be shown. explains
the characteristic difference Of weather In the
two. They and their related forms Of isobars
are subsidiary to the great primary currents.
Starting from the equator we have frat Q
region Of Gains and low ba rometer. tho dreaded
"dolirums," where vessels lie like painted
ships upon o painted ocean," Hero the cir is
rising. The doldrums form a sort Of col en-
circling the earth. At their outer edge are the
trade winds, and next comes the region OF great
anti-cyclones, where the barometer Is high and
the air is falling. Here arc the tropical belts
Of Gains, the horse latitudes." The great
Atlantic Anti-cyclone belongs to this region.
The trade winds skirt its southern foot. whilo
its northern side Is the birthplace Of innumer-
able cyclones Of every size and intensity" The
West India cyclones, or hurricanes work round
its northwest corner. and then, turning north
ward and eastward. follow the line Of tho col.
OF which we have previously spoken as lying In
winter between the Atlantic and the Mexican
North Of this region Of high pressure, whore
anti-cyclones most abound. comes the temper-
ate zone with Its ductuating pressures. through
which cyclones chase one another In endless
succession, and whore occasionally anti.cy-
clones OF considerable persistence are formed.
Upon the position Of these depend the prtnoi-
pal types OF weather.
Still further north we come to tho region OF
prevailing cold polar winds, which. penetrating
the south. at times produce marked Of
fects upon the weather Of the temperate zone.
dipping Of the earth's poles now owarda and
now away from the sun, owing to the inclination
of its axis to the plane Of it's orbit. tends to
o further fluctuRtion Of weather CON-
ditions. In summer. when the northern hon.
leans sunward, there must DO o Ren.
eral shifting Of the whole system OF atmos-
pheric pressures toward the north; and In win
ter. whom this hemisphere leans away from
the SUM-, a similar shifting must taxi place In
an opposite direction.
AS We view the earth in this light. then, We
see 1t surrounded by IN atmospheric ocean
which Is more restless than the sea itself III
heated surface Of the earth expands It and
drives 1t upward. the cold Of outer space con-
1t, and 1t sinks again. From the glowing
it flows Of to the snowy poles, and the
globe beneath throws 1t into diagonal
which. detected by q .ie 1sand minor
battle with conflicting forces. and
swirl into eddytng cyclones and anh-cyclones.
into this atmosphere. tormsnted
with ceaseless motion. risss the vapor OF the
ocean. The heated air thinks 1t up eagerly. But
as tho air rises In its turn the increasing cold
1t to surrender its vapor. which con-
denses and falls In rain.
Grouping all these things together. We have
the elements, or units. which mako up tho
weather. 1t requires but o glance to 500 how
1t Is to seek to base An exact science
upon them. Yet when We take o bird's-eye
view We can plainly trace the operation of