Spirit of the age. [volume] (Woodstock, Vt.) 1845-1913, 1908-10-03
Structure Of HailstOnes.
by CLEVELAND ABBR.

There are three plausible hypothe-
ses as TO the origin OF the snowy ice
at the centre of Maidstone,
(a) The hailstone may have be-
gun with the formation OF a ball Of
snow, and tho clear Ice may DO q
deposit of cold water, froSen few
seconds later by the cold OF the
surrounding atmosphere. In this
case the air that is mixed with the
snowy Ice at the centre would be
compressed by the freezing OF the
surrounding clear ice, and would be
liberated as a bubble when the hall
stone is melted under water.
OBJ The nucleus OF the Maidstone
may have been at first large drop
OF water, containing dissolved air,
which is forced out by the process OF
freezing, precisely like the bubbles
OF air that are seen In cakes OF arti-
fetal ice. Cold water can dissolve
an appreciable percentage of its vol
ume Of air, all of which is eTtruded
when water freezes; a bubble of
highly compressed air might thus be
formed at the centre of the hailstone.
II such hallstone be melted In cold
water slowly, all OF this air will be
redlssolved, and no bubble will be
seen to rise to the surface. If the
stone be dissolved In hot water rapid
ly, or especially II the stone be
crushed foTcibly and quickly under
water, the air may escape as a bub-
BILE without having had time to be
redlssolved.
(c) A hailstone formed of pure
water that has had no opportunity
to absorb or dissolve air can be re-
duced to temperature far below
freezing, but will eventually turn to
Ice, at which moment its tempera-
ture will rise to thirty-two degrees
Fahrenheit, and 1t will assume
crystalline structure, 80 as to re-
semble snow. Such a hailstone has,
therefore, a snowy nucleus without
inclosed air, and ON being melted
under water will, of course, show no
bubble. In fact, the central space
is occupied, not by air, but by the
vapor Of water only and as the
pressure is very small, we may liken
this to a partial vacuum.
All these three forms of hailstones,
and other forms as yet unthought
Of, are possible; and If we could in
vent methods of distinguishing be-
tween these three kinds of hailstones
we should have a better knowledge
OF what goes on In the upper air
uuiins the formation of hail
inose who have proper convent
enees Will find that the study of hail
tones under polarized light gives
additional information as to their
crystalline structure, but has not as
ct told us much about the process
u formation.
IS ice is poor conductor OF heat,
Is worth while to make some effort
} De- Zine the temperature of the
It-.lor OF large Maidstone. The
Eternal surface may safely be as
Lmed 10 have the temperature of
IapC. alton or the average wet
alb temperature prevailing in the
Mer thousand feet of air through
n.eh the Lail has rapidly fallen,
at the centre must be at tempera-
re more nearly corresponding to
at at which the nucleus was
,rined. There is, therefore, a state
! strain that should be revealed by
lnri1sd light. The average tenn
azure Oh the whole hailstone may
easily aaI dircctly determined by
wing La.l to melt within a
rini stei, where the heat con-
cd tHi lie detei mined, and then
te--p-tdtu.e be Computed
,-thly teView.