The Marietta journal. [volume] (Marietta, Ga.) 1866-1909, 1896-07-30
SCIENTIFIC IDEAS
About the Weather and
Causes OF Rain.
RELATION OF CLOUDS AND RAIN.
How they Differ, Sailing Across the
Continent, Producing Moisture.
Other Facts.

EDS. JCURNAL-W Why is it that so
so'called weather prophets, both
great and small, i4il to accurately
predict or toretell the character of
the weather only q few hours
ahead? | believe it to be positive
tact that 80 per cent Of the entire
population OF the globe do not pos
sess one iCta of knowledge as to the
scientific courses that produce rain,
hail or show. How many weather
prophets do you suppose are aware
that there are four distinct kinds 0.
clouds, how many of them have any
kno Wedge 81 the relation that these
clouds bear to each other in pro-
ducing rein, etc., how many know
tina. the chief and principal cause of
the formation of clouds is in the
wind? The four different clouds are
called Cirrus, Cumulus, Stratus end
Nimbus. Cirrus clouds are like
fibres or thin streaks and are the
most elevated of all clouds. Cumu-
lus clouds are those masses piled one
above another like mountains,
commonly called thunder.heads.
Stratus clouds are kind of mist
that usually rise at sunset and are
nearer the earth than any other
of the clouds. Nimbus is the latin
word for clouds which bring storm,
and refers in science to all clouds
from which rain falls. Now, Cum
illus clouds, when they are moving
IN contrary direction to the wind,
rain may be expected in the imme-
date course, but when they are
sailing across the continent with
the wind, they always indicate fine
weather. Cirrus clouds are produc-
ed by moisture in a visible form
deposited in the higher regions Of
heated air and are the basis of all
storms. Cumulus clouds are pro-
duced by masses OF visible vapor
passing from the places where they
were first formed to other places
where they are about to be dissolv-
ed or deposited as falling rain.
Stratus clouds are produced by cold
currents of air passing along close
to the earth's surface over visible
beds Of moisture. Now two things
are always essential in producing
rain, hot and cold current of air
blowing in opposite directions, the
hot current next to the earth to
cause evaporation, the cold cur
rent above to produce condensa-
ton. Warm dry winds passing
across the country, unless they
come in contact With cool current,
will simply convert The substance Of
clouds into invisible vapor which
they will carry away in their own
current, but if it meets a cool cur.
rent Of wind it will cordense the
invisible vapor of the air and add it
to the clouds, and rain is the result.
| often hear that clouds and fogs are
are different. They differ only in
one respect. Clouds are elevated
above our heads, while fogs come in
contact with the earth's surface.
This is caused exclusively by the
temperature of the air, when the
surface OF the earth is warmer than
the air the vspor becomes mist or
tcg, being condensed by the cold air
above, but when the air is warmer
than the earth, the vapor rises and
becomes cloud. | have often been
asked how clouds could float so
readilyin the air, because clouds
are composed of very minute glob.
ules, which being lighter than the
air float like sosp bubbles.
! have no doubt but that q great
many Of your readers are just as
familiar with the scientific causes of
rain, hail, etc, as / am. This ar.
ticle is not intended for the edifica-
ton OF that class, but is written ex&
clusively for the benefit Of "weather
prophets" GEO. j. Mon.