Green-Mountain freeman. [volume] (Montpelier, Vt.) 1844-1884, 1853-03-10
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From the Scientific American.
On the Causes of Rain,

On the Causes of Rain,
We have received circular bearing the
above title from Daniel Vaughan. His theory
is as foliows:--
That electricity pariakes Of the power of
sustaining vapor in the atmosphere is evden,
from several facts. When allowed 10 cvapofaie,
the surface Of water Is not only cooled. but is
also rendered negatively sIec'ufh,d, while the
v.por itself is positive. From this It appears
that the vapnE y formed at lh" joint expense of
heat and electricity. Experiments ais" prove
that evaporation IS retarded wherever the wnter
is insulated; result, wh,el, shows more conclu
s,velY the p,rt which the electric Aiid acts IN
the production "f vapor. Accordingly the amount
OF watery vapor which ,h. at'nusphera can CON-
tain. depends not only on its Temperature, but
likewise on its electricity. which, according To
all experiments, is much increased in Intensity
at great elevations, and here its agency becomes
important as that OF heat declines. the evap-
oratInn Of water and the friction Of The air
against the surface Of the earth. are commonly
regarded as the p'i 'cpaI sou,ces IF atnosp'e'i;
electricity; and, tu render the mechanism of
nature u'rc effective Tor Its development and for
contnng it to the upper regions, an insuaior is
prov dec by means OF the lower stratum nf air
which is most free from humidity, for the moist
air continually ascends on account Of it specific
gravity.
1t is we'll known that positive electricity is
always liberated henever vapor il condensed :;
and, should 1t escape he prevented by insulation,
the condensation will, of course be retarded
The non conducting puwer Of the lower stratum
OF air Will, therefore, be the means of keeping
tlr aqneons va'or dissolved in the atmosphere
until the INSULATION Is brnken by the near Hp-
proach of humidity to the earlh's surface or by
other causes. The electricity being then no
innger confined by proper barrier. should esca,e
to the earth the portion of vapor which WAS
) dependent on It's suppnrt. should condense, and
IN uost cases, descend as rain; while, at the
same time. the drops is approaching The suffice
Of the earth, shuuld salurate The earth with
nnistnre. and thus furnish means for the more
rapid discharge of electricity and the more com
plete precipitation Of the superAuous water Of
the atmospere.
Ia conseq lence Of the humidity of the at
mosphere, nluhniains Withdraw electricity from a
considerable distance; and by causing the des.
, cent Of rain open nnnerons channels BY which
the electric fluid passes from much greater dis.
! 'ances to the djtcent owlands. ~fne indirect
I influence Of m mntains, therefore, extends ma nv
! 'ries around them, and hence 1t is that they dr
, not themselves receive as much rain as he
plains and valleys in their vicinity though lhpi,
fleets on It's production IS too obvious to be
! dnnbled. In the VAST island or ,nrinent ol
Australia which contains no mountains, years
the sky is regarded AS phennnennn the rivers
ire all too insignificant Tor navigation. and most
Of them are quite dry during eight months OF
me year. A single river OF the mountainous
. region Of South America. contributes more wa
Ter 10 the ocean than all the rivers Of tho con
,,nnnt Of Africa. which is much more extensive
Even the principal African rivers rise in the
highlands under the equator, they receive scarce
any accessi IN Of waIer fro the lnwer districts
The part winch trees take IN the removal o
Electricity from The upper regions, is tar greae,
than might b. suspected from heir moderate elp
J. va'ion. They increase the anti,y of rain ant
J. cause It to tail IN gentle and seasonable sh,wcrs
e instead of coming in rare and vlolen, torrents
n Thai the obstruction of forests Ia attended will
p dl,nlnnllon OF rain, is fact proved beyon,
II donbt from observations made on his con,inen,
a and. accoring to Humboldt and Boussnual, /,
y The soine result ls visible in Sunih America.
2 From the result Of The experiment. Of pa,u,s
il is evident that by d,.eharging he elec, ic,,
In the upper part Vt our atmosphere, we ma
10 deprive rain Of lis injurious effects. and not onI
G. render it more beneficial TO our wants ana
~ the purposes Of agriculture, but even exten
70 those benefits to the sandy deserts and redes