Marvels of the Universe 707 
storms are recorded by several French writers, 
including the famous astronomer Flammarion. So 
we find insurance offices against damage by hail are 
to be seen in most Continental countries. 
We used to be satisfied with the statement 
that Hail was nothing more than frozen drops of 
rain. But this definition does not satisfy the 
scientific mind of to-day. Every department of 
science is undergoing the scrutiny of keen specialists. 
Nothing in Nature is, to them, too small or too 
insignificant for close examination. This being so, 
Hail is raised to a position of equal importance 
with the snow-crystals and other beautiful forms 
of water. 
Hail is often the accompaniment of a storm at 
a time when the surface temperature of the earth 
is extremely high, and the process of cooling is 
correspondingly rapid; this cooling of the air is 
continually going on, for all hot air ascends, and, 
consequently, becoming cooler, is absorbed by the 
sun’s rays in the form of vapour; but it is only 
when this condensation takes place with peculiar 
[Bu M. Quénisset. 
A transverse section of the central Hailstone shown 
on page 709, showing its formation of a_ series of 
hexagons round a central hexagonal core. 
rapidity that Hail is formed. The greater cold necessary for freezing Is provided by the rapidity 
of the evaporation taking place over the earth surface ; for evaporation has always a tendency 
to lower the surrounding atmospheric temperature. 
Now at the time of a storm the air-currents are 
often of very varied temperature, so that the substance falling from the storm-cloud, be it either 
a rain-drop or a snow-flake, is affected by the vary- 
ing temperatures through which it has had to pass. 
It is melted and congealed often many times before 
it reaches the earth, and this rapid series of 
transitions causes it to take the ultimate form of 
an ice-mass or Hail. It is not necessary that these 
variations in temperature should be remarkable ; 
a few degrees above and below zero would be 
sufficient to affect the transitions from ice to water. 
Not only does the atmospheric temperature affect 
the form in which the water vapour returns to 
earth, but the electricity present in the storm-cloud 
is in some degree responsible for the phenomenon. 
Hail-storms are noticeable for the presence of 
electricity in a high degree. 
It may possibly surprise some of our readers to 
learn that /arge hailstones are not simply frozen 
quantities of water that have fallen directly from 
the clouds, but that in the process of growth, or 
of enlargement in bulk, they have fallen as small 
particles from clouds of enormous height ; have 
descended, it may be, a thousand or more feet ; 
have ascended again to a great height ; have fallen 
[The Monthly Weather Review. 
A Hailstone which was taken up at Morgantown, 
W. Virginia. It measured roughly two inches in height 
and-had a-volume of about one cubic inch. 
