River Falls journal. [volume] (River Falls, Pierce County, Wis.) 1872-2019, 1906-04-05
MAKING OF HAILSTONES.
An Atom of Dust Is the. Nucleus
About Which Moisture
Freezes.

Ii one would know how hailstone IL
formed he must first dissect it. He will
find that it is composed of quantity
OF tiny crystals arranged in concentric
rings or zones, and each zone in turn Will
have its evidence to give concerning the
making of the hailstones on it's way to
the earth
An atom of dust is the nucleus OF
each hailstone These atoms of dust
pervade every part of the atmosphere
and are found not only in the lower
strata of the air. but the winds carry
them to the tops of the highest noun
ta1ns. So that, no matter whether SAM
pies of air are obtained by balloonists or
mountain climbers, minute particles OF
dust are always to be found in them
1t is coming to be believed that without
these atoms of dust upon which tbs
moisture of the air can settle there would
be no raindrops, no fog, no snow, dew,
clouds or hail. Without these minute
platforms, as they are called, upon which
the moisture condenses as it alights,
rain woAld be continually pouring down
atmosphere buoyed UP till such times
as circumstances compel them to yield
up the supplies they have collected. If
a little ~vapor should happen to con-
dense on a particle of dust floating aim
lessly about in the air there is the be-
ginning of what, under favorable cir
cumstances, will become a full-siZel
hailstOne.
The hailStOne to attain great size
must plunge to the earth from great
height The clouds which float at the
greatest distance from the earth arc
those known as the cirrus, and are often
many miles above the tops of the high
hailstorm can only dive to the earth
from this height it will, in it's headlong
flight, pass through strata of air differ
ing very much as regards temperature
and moisture, and these are circum-
stances must favorable to its develop
ment. But before it can begin it's de-
scent it must find some way of being car
ried up to these heights. So the jour-
new is made by getting into the way of
one of the. strong ascensional currents
which spring upward from almost every
part of the earths surface.
In such place it is not long be-
fore the moisture on the atom of dust
freezes. The form which the frozen
moisture takes depends upon circum-
stances. but there are many possibili-
ties before it. 1t may crystalline as
tiny pellet of snow, or may take the
shape of an ice crystal or simply the
form of frozen raindrop. Any of these
shapes will serve as an excellent begin
ming for a further change.
1t is easily understood that the force
of grayitation has been constantly pull
ing this atom of dust and its CONCEALED
moisture toward the ground. AS it
starts on its journey back to the earth
it will pass through strata of air which
differ greatly in moisture and tempera-
ture. Some of the air will be above
the freezing point and other layers will
he below it, while it will be no uncom-
mon thing for the hailstone to dash
through a cloud some thousands OF feet
thick. The hailstone itself, with its
heart of ice, is always below the freez-
ing point, so that any moisture which
settles upon it is promptly. frozen and
forms a girdle of ice about the nucleus.
When the Maidstone passes through
the air that is below the freezing point
the moisture settles upon it in the form
of a clear zone of ice, while, on the other
hand. when the air is moistened and its
11ooict11rn is above the freezing point the
girdle of ice is Opaque.