The Sunday herald and weekly national intelligencer., 1891-08-09
OBSERVATION-DISCLOSURES.
Physical Nature and Internal Condition
of Gases.


Physical Nature and Internal Condition
of Gases.
Good Words
or all the exciting causes OF luminosity none
is more powerful or more remarkable in its
action than electricity. A discharge of cleo
tricity sent through rarefed gas is attended
by glow the color of which is often charac-
teristic OF the particular gas; and not infre-
quently the gas continues to give out light for
some time after the apparent cessation OF the
electrical action. BY reason of the beauty
and the remarkable appearance OF stri@, or
dark and light spaces, arranged in symetri-
cal manner in the track OF the glow and
round the poles, together with other mani
festations, these phenomena have been the
occasion of much observation and study on
account of the light they are calculated to
throw on the physical nature and internal
constitution of gases, and on the manner In
which their molecules behave under the in
tiuence of electricity and and magnetism.
The pheunomena observed in gases In con-
ditons of extreme tenuity have been especially
studied by Mr.. Crookes. Under these cir
cumstances the tube or vessel containing the
highly.rareied gas, IL Of soda glass, phospho-
resces with yellowish green light, due to the
impact OF the rapidly moving molecules on the
surface OF the glass, and round the negative
pole in the tube is dark space with a
luminous boundary, due probably to the col
This molecular bombardment is capable of af-
fording some OF the most striking and beauti-
full examples of phosophorescence with which
we are acquainted.
Substances which are phosphorescent under
ordinary conditions glow with the greatest
brilliancy when submitted to the negative dis
charge in these highly attenuated gases.
Canton's phosphorus shines with all the
splendor induced by strong sunshine. Under
the same circumstances the diamond, especially
that from the South African fields, phos-
phoresces with brilliant light blue color.
Diamonds from other localities were found by
Mr.. Crookes to shine with all varieties of
color, such as bright blue, pale blue apricot,
red, yellowish, green, orange, and bright
green A green diamond when phospboresc-
ing in good vacuum gave out almost as much
light as a candle, and the different faces of the
naturally-crystalized gems were found to
glow with different shades of color.
The ruby, which is practically almost pure
alumina, phosphoresces with full rich red.
A number of rough rubes in high vacuum
glow, when the molecular discharge plays
upon them, as If they were red-hot and with
an illuminating effect almost equal to that OF
the diamond under the the same conditions
The color of the ruby has apparently little or
nothing to do with the phenomena; pure
white alumna rubies of pale reddish yellow
and gems of the ''pigeon blood" color oil EN- it
practically the same deep red glow. The arti-
fetal rubies of Messrs. Frenzy 81 Fell, which
are OF the same chemical nature as the natural
stone, behave in precisely the same way when
subjected to the discharge in a sufficiently
high vacuum, showing that in this as in all
other respects the natural aud artificial rubies
are identical in character. The sapphire, how
ever, which In chemical composition differs
but slightly if at all, from the ruby, gives out
bluish-gray light, while the emerald CLOVIS
with fine crimson-red color.