, 1873-07-11
PROF. WIsE's BALL0ON-V0YAGE,

to onAt, with O delccti0n from tho equator, 1B
known by ovory meteorological to DO just Oh Ger"
tain as tho current Of tho traao-winds In tho
Torril Zone, aud to bo due to tho operation Of
tho samo CAUSES, to wit: tho heating infl1-
onces Of tho sun, and tho rotation Of tllo oarth
upon hor azis. It Is not difficult to understand
tic general Inv Of air-moyomont.
Tho land and wntor which compone tho oarth's
suraco nro hoated by exposure to tho solar rays,
aud aro most highly hontod whore those rays are
vertical; tlo avorngo position Of tho limo Of
greatest forco being naar tho cquntor. The au-
porincumbont Dir becomes hoatod. by radintion,
and 1iHoH in consequence; It's place being supplied
by cooler air from groator latitudcB. Tho hoatod
air cools aa It riaos, aud necessarily flows over
towards tho poles. Wo thus hnyo System Of
circulation established in each hemisphere. In
tho northern hn1f OF tho globe the air ut tho
faco Of tho earth tends southwark, and ia COM
ponsatod by an upper current that touds north
ward.
Tho air, like any ao1id body, ia carriol round
by tho daiIy rotation Of tho oarth on ler a1iH.
Tho velocity varioa with tho latitude. At tho
equator, oil objects moyo At tho rate Of 24.900
mf1oa in twanty-four hours, or noarly l, ,0io mles
por hour; ,ghilo at tho polca tho forward move
mont of rotation is nothing. Hence tho voloci-
ty decreases with an increase OF latitude; being
900 mileB por hour ut 80 degrees, aud nearly Gao
miles at GO degrees OF latitude. A volume Of
ar TINT iB caused to moyo southwark or north
ward, by tho action Of tho sun, retains its orig
ii,al eastward velocity for somo time, and changes
it yory slowly, as consequence Of friction.
1Ionco In passing northward in this
hemisphere, ita original eastward vo1oci-
ty being groator than TINT Of tho
surface over which it "blows," 1t moves faster
than tho earth at tie latter place. and gives the
phenomenon Of wind from thcsouthwcst. Sim
narly, in moving Bouthward, it lags bohind, and
sooms to blow from tho northeast. In tho North
crn Hemisphere tho wind always tends to tho
right OF tho original impulse; as do all other
moving boaios, from tho same CAUSE. Tho ton
doncy of q swift-moving railroad train to run OF
tho track to tho right, ia u familiar example.
Without stopping to describe tho way in which
these two forcos oporato, in conjunction with
secondary causes, to produce "Bet " Of wind
in other directions at difroront portions Of tho
earth's surface, wo may noto that tho upward
rush ut tho equator is supplied directly by mir
from the Torrid Zono, which ca1lHcs tho surface
phenomenon known as tho trado-wind, blowing
from tho northeast in tho Northern Hemisphere,
and from tho southeast in tho Southern Homi-
eplore. It also causcs m upper current, which
in tho North Temperate Zone moves Htoadily
from tho southwest.
Experience shows us that oven over tho land,
tho motion Of this upper current il steady and
continuous, tllough tho mir Of tho surface may
DO lashed into angry commotion. And science
confirms this with ler reasoning: tho chief
causes Of meteorological disturbance lie near tho
eartlls Burfaco and thoir effects arc lost in tho
upper regions of tho atmosphere. It is we'll
known that most Of tho woather-changes in
which VIC tako practical interest occur within
ona-tlird Of q milo from tic ground !;
though c!ouda ofton exist Mt much
greater altitude. Honco tho upper air is
comparatively FREQ from irregula1ity Of move
mont Or condition. Wo may add that while
tho upper current il equally cortain ovor tho
ocean as over tho land, being duo to tho opora-
ton Of general causo, 1t is ovon less liable to
disturbance. The conditions of tho atmosphere
muHt bo unusually disturbed il tho balloon-yoy-
ngors experience amy back-set Of curront, or any
| deviation from sorone course from tho time
| thoy riso above the usual cloud-bearing regions
OF the atmosphere till thoy again pass through
| them in tLoir doBcont to earth-or water.
| There is, however, room for grave doubt that
! this curront would carry d balloon to tho com-
morcal part Of Europe, or oyon to any portion
| Of that continont. Tho due northeast course
from Now York would carry the air-Bhip over the
Arctic Ocoau, nearly midway betwoon the north
of Russia md the coast Of spitzborgon, whore
tho extromo cold would condonso the gas &c
much rs to put u summary end to tho journey
out Of Bight Of lind. It las been snggoated by
ono scientific authority, that tho balloon will
make Sweden or Norway, which is pos
| bio. Tho conductors of tho trip aro I'M.
dorstood to expect that they will bo able
to follow tho conrao Of tho Gulf Stream
u,,l striko land somewhere In tho southern hall
Of Europe. This is exceedingly problomatical
II, howoyor, 1t Yyero possible to calculate with
certainty OIL a satisfactory coureo (using tho 1as
word In itB nautical HonBo), tlloro aro still ma,
aoyero risks to DO r1ln, most of Which can oni,
bo rcasurably provided for. The Eoyagors mn,
make allowance for tho unavoidable erosnosis
or escape of gaa through tho material Of thu
balloon, but they cannot DO suro that thoy vii
not pass through a snow-cloud that will forco I
descent into 1nid-occan. It il probable, too
that great physical difficulty will DO oxpo
riouced in broathing highly-rarofel nj
for several days. especially by those Wit
lave had no experience in tho uppor atmos
pl.oro; aud lilo result may bo ligl,t-hoadodnoss
in its metaphorcal as we'll as litoral sense, tia