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delicate, silent action of this beam Within the ice that I
now wish to direct your attention. Upon the screen is
thrown a magnified image of the slab of ice: the light of
the beam passes freely through the ice without melting it,
and enables us to form the image, but the heat of the
beam is in great part intercepted by the ice, and that heat
now applies itself to the work of internal liquefaction.
Observe those stars breaking out over the white surface,
and expanding in size as the action of the beam continues.
These stars are liquefied ice, and each of them, you ob-
serve, has six rays. They still more closely resemble
flowers, each of six petals. Under the action of the heat
the molecules of the ice fall asunder, so as to leave be-
hind them these exquisite forms. We have here the pro-
cess of crystallization reversed. In this fashion, and in
strict accordance with this hexangular type every ice mole-
cule takes its place upon our ponds and lakes during the
frosts of winter. To use the language of an American
poet, “ the atoms march in tune,” moving to the music of
law, which thus renders the commonest substance in Na-
ture a miracle of beauty.

It is the functioknwof science, not as some think to divest
this universe of its wonder and its mystery, but, as in the
case here before us, to point out_theu_wp‘nder and the
mystery_moificommonflthingjs. Those fern-like forms, which
on a frosty morning overspread your window-panes, illus-
trate the action of the same force. Breathe upon such a
pane before the fires are lighted, and reduce the solid crys-
talline film to the liquid condition, then watch its subse-
quent appearance. You will see it all the better if you
look at it through a common magnifying-glass. After you
have ceased breathing, the film, abandoned to the action of
its own forces, appears for a moment to be alive. Lines of
motion run through it; molecule closes with molecule, until
finally the whole film passes from the state of liquidity,

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