Evening star., 1936-02-16

Intricate Patterns Form
Great Elemental Mystery
Formations Far From Simple Things They
Appear to Be to Naked Eye-Ice Really
a Mineral, and Remarkable One

great variety Of shapes, hundreds Of
which have been drawn and photo
graphed with the aid of the micro
scope.
Hoarfrost occurs not only on out
door objects, after clear, frosty
night, but also indoors on window
panes, refrigerating pipes and other
cold surfaces. Not all the so-called
frost figures seen on windowpanes.
however, are due to hoarfrost. Many,
including the long feathery, or fern
like forms, result from the freezing
of thin film of water on the pane,
and have sometimes been distin-
gulShed as "WindoW-ice."
Some of the most beautiful de-
posits of true hoarfrost are found on
the surface ice of lakes, streams and
glaciers. They are known as "ice
flowers" Hoarfrost should not be
confused with the rough or feathery
coating of ice deposited on terrestrial
objects in cold weather by drifting
fog. This is now termed "rime" by
meteorologists. One more distinct va
riety of ice is known to the Weather
Bureau as glaze" though it is more
often called "sleet" by the general
public and by the engineering profess
sion. This is the smooth and nearly
transparent coating formed on wires,
tree branches, pavementS and other
objects by a cold weather rainStorm.
Its occurrence on a large scale is
called an lice storm"
Newspaper reports that the rivers Of
Alaska were freezing upside down
/. e., from the bottom upward-created
widespread interest one Autumn
few years ago, though the process in
questionable formation of anchor
ice"-l a very common one. even
in the United States. In our latitudes
such ice forms when the bottom of
stream or other body of water
becomes very cold on account of the
nocturnal radiation of heat through
the water to clear sky overhead,
but where permanently frozen ground
exists at moderate depth the chill
ing of the bottom below the freezing
point is partly and perhaps chiefly
due to the proximity of such ground.
WRITING of Northern Russia, w.
W G.Bogoras says:
"On account of the ever-frozen
ground, the rivers begin to freeze, not
only from above, but also from be-
meath. Very soon the water flows
as If incaSed in round tube Of frozen
al Tha c1Yrfan chnnt Of iNa
is formed of small tablets, thin and
brittle as the thinnest glass, but on
the very bottom the water begins
to form the bottom ice, the so-called
'salo," which has the shape and con-
sistency of half-dissolved snow. In
this double manner the river freezes
with the utmost rapidity. Shallow
currents in the mountains in more
quiet places freeze to the bottom"
Some Winter morning you may wake
up to find your lawn covered with
big snowballs, as if a whole regiment
of brownies had been disporting them
selves during the night. 1t Is rather
rare that the wind and the tempera-
ture are just right to produce what
science calls "snow-rollers," and when
this happens the resulting spectacle
is generally very striking.
The rollers are cylindrical and more
or less followed out at the ends, so
that they have the general shape of
that once familiar item of the femi-
nine Winter wardrobe, the muff. In
size they may be as big as barrels,
though they are generally much
smaller. Each of these cylinders has
been rolled by the wind and lies at
the end of a long trough in the snow,
marking the path along which the
rolling has occurred. The trough is
narrow at the end where the rolling
began and gradually increases in
width toward the final position of
the roller.
The nucleus of a snow-roller is
either lump of snow scooped up by
gust or projection from the snow
surface which the wind topples over.
AS this is rolled along by the wind it
will increase in size, provided the snow
is of the right consistency. Loose,
fluffy snow. only slightly damp, seems
to be the most favorable for the pro-
duction of snow-rollers.
On frosty morning, after a night
free from wind, curious fringes, rib
bons or masses of ice are sometimes
found among the dead stems of GER
tain plants, frequently called frost
plants"
The water that forms these fringes
is brought up from the soil by capil-
larry action and comes to the surfece
mainly or wholly through row of
minute openings. The fringe begins
as row of separate hairlike crystals
which merge into continuous ribbon
as they grow outward. Why they
should form in a narrow line along
the stem rather than in broad patches
is puzzle, and theer are still others
connected with their formation.
ONE variety of ice that always
arouses the curiosity of the lay
man. If he happens to notice it, con-
sists Of little columns or pillars an
inch or few inches in height, formed
in compact clusters on the surface of
bare soil. These columns grow up
from the ground, sometimes carrying
q thin layer of surface soil or a thin
horizontal crust Of ice, while in still
other cases the upper ends of the COL
umns are separate. The columns are
usually vertical and parallel to one an
other, but in some cases they are
spread apart so that they bear a cer-
tain resemblance to tufts Of grass
One of the rarest of Winter spec