The Wilmingtonian, and Delaware advertiser., 1826-11-23

paragraph:
at is admitted that currents of wind are pro-
duced by the air rushing towards the place where
a rarifaction of the atmosphere has taken place.
If so, why does not the wind blow from the poles
to the equator, where it is allowed, the atmos-
phere is more rarified, at all times than at the
poles. It may be said that the inequalities OF the
surface of the land produces the variety of cur
rents; but this would not satisfy, or solve the dit
fculty, as relates to the ocean, There is smooth,
plain on the ocean, from the poles
to the equator, yet there is diversity OF currents
Of air Can some of our Philosophers explain
this' If fthey can, by so doing they will oblige
DESULToRI HEADER"
Now it is not admitted that currents OF
wind are cizyays produced by the air rushing
towards the place where rarefaction OF the
atmosphere has occurred. Wind may be
pro luced by any cause which destroys the
equilibrium. The contents OF
a pond may be moved by letting in, as well
we'll as by letting out, a current OF water.
The equilibrium of the atmosphere will be
disturbed by change of elasticity, as we'll
as of specific gravity. The atmosphere be-
ing supposed at rest, if the elastic force of
any portion of it should be suddenly increas-
ed, an expansion in every direction, and con-
sequently wind from that portion must en-
sue. But this motion by changing the spe-
cific gravity of the expanded air, destroys
the equality of the ateralpressure from gra-
witty, and produces reauent pulse, or wind
toqvard the rarefcd part. Motions in the
opposite order must result from the sudden
decrease of atmospheric elasticity.
The atmosphere being charged with aque-
Gus vapor. must be subject to numerous va
riations Of density and elasticity from the
changes experienced by the vaponr. By
chemical experiments it appears that water,
when converted into vapour, absorbs and re-
tains in "a latent state, quantity of caloric
sufficient to raise its temperature above 300
degrees the formation Of aqueous
yapour must be attended with great abb
sorption, and its re-conyersion into water,
with copious emission of caloric. And as
vaponrs are almost continually forming OF
precipitating in the atmosphere, the equili-
brium of gravity and elastic force, must from
this cause, be subject to almost perpetual
perturbarions.
The wind over land is affected, not only
by the irregularities of surface, but by the
kind Of surface, and even by the degree o
cultivation; for these circumstances exert ar
influence upon the temperature, and there.
fore upon the equilibrium OF the atmosphere
and winds produced on land,extend ofnecessi
ty to the adjacent waters. The monsoons in thu
Indian and Etheopic seas, are explained by !
ference to the contiguous shores.
The air within the tropics is unquestion
ably more rarehed, than in the vicinity O
the poles: and general translation of thai
portion of the atmosphere which is centigu.
Gus TO the surface, towards the equator mus1
occur: but the air, in these migrations. j:
continually arriving at parallels of latitude
where the diurnal velocity Is greater thar
on those which have been left; and there
fore the direction of the wind will be com
pounded of real and an apparent motion
Hence, in this latitude, the prevailing wne
is North Westerly
The attraction Of the sun and moon. ne
cessarily produce aerial as well as aqueous
tides; or in other words. change the atmos
pheric equilibrium, and, Of course, produce
wind
The winds, by their mechanical action, ex-
cite currents. These currents, as we'll a.
those resulting from the tides, are modified
BY the situation of the surrounding shores
and exert direct influence on the superen.
cnmbens air by mechanical action, and al
Indirect one by their temperature, and thu:
affect the atmospheric equilibrium
These principles, though sufficient simple
in their nature, evidently produce very com
plcated results; SO that no one who consid
ers the subject m all its boundless variety o
ever varying processes, will be surprised
that even on the broad ocean such variation:
are observable in the direction and velocity
| of the aerial currents. l..
| PRINTING
| ANY improvement connected with this en-
gine of intellect and freedom is of universa
interest, and IN this country especially, i!