Evening star. [volume] (Washington, D.C.) 1854-1972, 1931-03-08

from an alrplane ny1ng above the CLOUDS. 1nlS
test, although originated primarily for clearing
the ocean of air of such Objectionable barriers
as cloud banks which might impede aeronauticaI
scouting from on high, also proved that storm
clouds could be attacked scientifically in such
manner that they would yield their contained
moisture in subsequent natural precipitation.
At McCook Field, in the presence of Wilbur
Wright and other aviational authorities, the
firing" of electrified sand from speeding air.
planes not only resulted in the dispersion or
Objectionable cumulus clouds but also produced
light rainfall which is said to have "splashed
to earth shortly after the sand was distributed
from the plane"
DR. WARREN equipped the plane used in the
Boiling Field flights with special metal
cone inches in diameter at its large end,
one-fourth as large at the small end and 2
hands high. This cone was employed as q
distributor in releasing the sand from the plane.
The arrangement was such that special motor
connected to the cone turned it at a speed Of
$50 revolutions per minute. The sand was in
troduced from a tube into the small end Of the
cone. The centrifugal force developed IN the
rapidly revolving cone held the sand its
inner surface, where the grains were charged
electrically, one side of the cone being linked
to electrical circuit Of $4,000 VOLTS the other
pole Of this circuit being grounded.
This large voltage was provided by the use
Of o high-tension generator connected to a
transformer. The sand which fell from the
lower and larger end Of the cone in the curious
cloud warfare was charged either negatively or
positively. This charging could be changed as
desired by shifting the ground terminal The
principle upon which the cloud and fog dis
persal tests was based was that the charged
grains of sand colliding with q moisture
saturated cloud would either cause it to break
up or else would develop rainfall.
sf1rI1 ne fIv ot
attitudes Of 1000 to 1000 feet were disspated
quickly when first attacked from the air in this
novel manner at. McCook Field. The expert
mentors even mounted an electrogcope in the
"sand-shooting ship in order to determine the
clarity OF the clouds which were attacked This
instrument proved futile, however, for such q
purpose, and consequently the military scien-
lists failed to determine whether the clouds
contained negative or positive electricity-n
either.
One cloud 1000 feet long and one-hah as
wide was shot" at an elevation Of 5000 feet
and, according to the War Department records,
was dispersed in three minutes by the electrified
sand fire. Later tests with a similar airplane
which was not equipped with fog dispersal
apparatus were apparently successful in de-
Stroying certain clouds merely by the blast
action of its racing propeller
IN the initial tests small airplane was used
which accommodated only 100 pounds of sand
as cloud-destroying ammunition. Subsequently,
Martin bomber with a sand capacity Of 700
pounds was employed. This big flying machine
was used In attacking dense stratus clouds
which were loaded with billions Of prospective
raindrops. All attacks the large, dense
clouds with this machine failed although it was
successful in dispensing the smaller clouds of
similar variety.
NOTWITHSTANDING the variations in these
experimental results, the McCook Field
experiments have been mentioned "as epochs
in artificial weather-making," in that they
produced light shower as result of cannon
aiding storm clouds with electrified sand.
Weather experts and meteorologsts on the
other hand, refuse to credit the Army Air
Corps research as authentic. They claim that
man-made weather is exactly as impossible
today as it was before the termination of this
military research.
The United States Weather Bureau says that
under certain atmospheric conditions when the
humidity is high clouds are constantly break
ing down and disintegrating in one sector Of
the sky while they are reformed in another
They contend that the cloud and fog dispersal
results of the War Department tests were
founded incorrectly on this popularity. Science
reports that under certain conditions-when
the air Is saturated and expanded under suit
able humidity conditionS-the introduction Of
sand or dust particles or even smoke into a
weather-ripe cloud would result in subsequent
rainfall no matter whether those particles we're
or were not charged with electricity.
thundershower results in nature when
warm air loaded to capacity with moisture as
it ascends from the earth is cooled gradually
until the dew point" is reached. Thereupon,
the water vapor forms cloud and If sufficient
dust particles, smoke similar media are
present upon which the water can condense
small droplets are produced which increase in
size due to friction as they plunge to earth.
Science explains that the exact temperatures
OF the dew point varies with the amount Of
moisture In the AIR. The dew noint il hi0h
II large amount Of moisture occurs in the
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