Frostburg mining journal. [volume] (Frostburg, Md.) 1871-1913, 1892-01-30

Without IL There would Bc No Knln
Snow Hail.
A highly interesting article ON dust"
by j. G. Mcpherson describes the dis.
Covery made a few years ago by Mr.. john
Aitken, of Falkirk, Scotland, in regard
to the presence and behavior of dust par
ticlcs in air and water and especially in
the atmosphere. He found that without
such dust there could be no rain, moth
ing but continuous dew i'll moist eli
mates. There would be no need for um.
brellas, but also no means of preventing
the skin and clothing from being con-
stantly wet. Invisible dust is absolutely
necessary for the production of fog,
cloud, mist, snow, slect, hail, and rain,
their fine particles acting each as Il nu-
cleus around which the vapor i'll the air
clusters to form a cloud particle. BY
means of an ingenious apparatus these
dust particles have been counted. and
found to range from about 5; 900 ,O0o
down to only "a in the cubic inch of air
The greatest number was found in room
after crowded meeting. and the least on
the top of Ben Nevis, which is the high
est mountain in Scotland This cxpodes
the old theory that the particles OF water
vapor have TO combine with each other
to form cloud particle, and perhaps
may lead up to "A revision of the theory OF
artiIicially producing rain, unless that be
abandoned altogether 1t leads up to the
idea that granting sutlicienCy of moist
ure in the air it may be made to con-
dense by scattering among it large
number of dust PARTICLES each of which
will attract around it the material for
part of cloud, that being the first step
in the process of producing rain, for
which mere detonation, however great,
is Intellectual
Mr. Aitken has also shown that tho
brilliancy and variety of the coloring
often observed at sunset are due to sus-
pended dust in the atmosphere. He ar
CUES that in the upper air there must
always be dust, for without it no clouds
could be formed to shield us from tho
suns scorching rays, and of cosmic dust
there must be n considerable quantity
suspended iii the air, which is produced
from the waste Of the millions of meteors
that daily fall into it. The tremendous
cruptions at krakatoa in the Straits of
Sunda, are computed to have thrown up
no less than 10000 cubic yards of dust
which actually fell around the volcano,
while the decks Of vessels hundreds of
miles away were covered with it. Much
of this dust remained in tho air for sew
eral years, and gavo the brilliant sunsets
so often described. II our atmosphere
were perfectly devoid OF dust the suns
light would simply pass through without
being seen, and total darkness would en-
sue soon after the sun dipped below tho
horizon. The length of our twilight,
therefore, depends upon the amount of
dust in the atmosphere. And this leads
up to a thought not stated in the article.
1t is that the argument adduced to provo
that the moons atmosphere is not sui1i-
cirnt to balance more than the Both of an
inch of mercury in the barometer may
be a bad one, IL amuch larger quantity
of air than that were free from
dust PARTICLES there would be an
absence of the rcfraction which
has hitherto been supposed INSOFAR
able from an aerial envelope Hence
the moon may have more air surrounding
her than she has hitherto been credited
with, but there would be no opportunity
for the snowfall which some have fan
cied to occur recently on our satellite.
The sources of tho dust in our atmos-
phere are numerous, in addition to those
previously mentioned. On and near the
sea the air is impregnated with brine
dust. But burned sulphur is the most
active of all substances as fog pro-
ducer in the cities. No less than $50 tons
OF the products of the combustion of
sulphur from the coal used are thrown
into the atmosphere of London every
day in winter. But the powerful dcod-
orizing and antiseptic properties OF tho
sulphur assists in sanitation, and the
writer hints that it may be better to bear
the Inconvenience Of fogs than be sub
jected to the evils Of a pestlence. This
smoke can, however, be dissipated by
electric discharges, and the air is in this
way cleared by lightning. The organic
germs that float in the air are also causes
Of disease as well as filth, but they are
less harmful than they would be il not
repelled from the lung surface of the
healthy human being who brcathcs air
containing them.-Chicago Tribune.