Omaha daily bee. (Omaha [Neb.]) 187?-1922, 1916-05-12
Why Rain Drops Are Round


MAILING rain forms into spherical drops for the
Il Same reason that the earth has become globe,
VIZ: Because that is the shape in which tho
internal forces Of attraction attain balance In the
Of very large and massive body ike the eartn
IL the attraction OF gravitston that controls the
form but IN that OF small body like rsjndrop It Is
the molecular attraction Of the infnitesma particles
The intensity Of molecular attraction which Is
the that holds the componens Of bodies together
is greater than that Of the attraction Of graya-
ton but II Is exercsed over comparatively insis
nincant distance In each case however. the result
ant OF all the attractions between the individual par
tcles IL force directed toward the center OF mass
But. by the principle Of inertia time Is always re-
1uirod for any force combination % forces 70 set
matter in motion The larger the volume Of matter
concerned the longer Will be the time needed for the
internal forces group s the particles synmericaly
around their common center Of mass
Thus when you pour out water from pail the at
traction grayitation brings II down TO the ground
Ia a shapeess mass before the molecular attraction
OF s particles has had sufficient time 10 form II into
drops. But II you should empty your pail from the
ton ~ the Woolworth building the water would
sprinkle passengers in Broadway with minute spher-
cal drops because first. the resistance Of the air
would break II Up into small masses. and second. the
molecular forces In these small would have
time 70 group their particles into minute globes
II ia upon this principle that the old-fashioned shot
towers are operated Molten lead IL dropped from
great elevation after passing through sieve 10 faci
tate rs separation into small masses and during their
downward flight these rounded into little
spheres by the mutual attraction Of their molecules
which group themselves around common center
with very large bodies, not broken up into small
portions, the grayitational force plays the principal
part In shaping them because graytauon Is effective
at great distances and throughout masses, whl3
cohesion or molecular attraction. IL extremely limited
with regard 10 tho space over which IL acts.
afh a
cules close around H. and these In turn attract their
immediate negbbors within the space occupied by
randrop tho molecular attraction Is the master force
ana quickly shapes the into sphere
And just 40 a spoonful Of water thrown from n
high tower will descend In the form 81 one or more
round drops owing the resultant pull Of all It's mole
cules toward center, the entire ocean II
Il were flung out into open space would become a
gigantic ball OF water rounded into that shape by tho
grsytatonal attraction acting throughout It's whole
mass.
II s by no accident that all the planets spher-
ical They have taken that shape as inevitably a
loose stone rolls down steep hill Their forms are
not perfect spheres they have been subjected
to outside disturbing forces such the centrifugal
effects OF their rotation their and the deforma
ons produced by the attraction OF other planets and
OF tho Even the heads OF comets are srheroidal,
although they are believed TO consist OF swarms ~
small bodies like meeors. This tendency OF masses,
whose component parts particles free to move
among another, to assume globular outline, Is
curously illustrated even by crowds swsrms OF
sentient beings Thus a OF bees when 1t gath
ers close becomes spherical spherodal since that
form Ia best suited TO nclose the greatest number OF
individuals. A human crowd certainly would take
spherical form n It's members able TO choose
their positions freely in up-and-down in hort.
zontal space. Being confined to one level, they ar.
range themselves In circle which Is the section OF
a sphere,