The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1901-02-10

the perfection Of a luminous paint Of a last
ing quality. Luminous paints now appear
ing on the market are made OF SUPPLIES OF
calcium and strontium. which must be ex-
posed TO the light a long while before they
can radiate it in the darkness. In other
words, they radiate only such light as they
previously absorb, and when that supply Is
expended they completely darken. But
radium need not absorb light before giving
1t of. Quantities kept in a leaden. x-ray
proof box two years were as radiant as ever
when unpaeked.
Radium emits rays found to nave the fur
Their power of rendering the air through
which they pass a conductor of electricity
An electromagnetic brought near them will
defect them from their direct path. No
one can venture now to predict the result
of thus opening up through the air direct
paths for electric currents to follow. IL
each ray from a radium lamp is in itself an
electric wire, great possibilities are certain
to be revealed by physicists.
Rays from a radium have also the power
OF transforming oxygen into ozone. Rooms
lighted thereby will perhaps receive in
this way purer, more wholesome and more
refreshing atmosphere. stimulating the
= - 62C8NCA ooh1 ONO
action than rooms lighted by lamps breath
ing out carbonic acid gas. Moreover, the
radium rays. unlike those from present
artificial light, do not raise the tempera-
ture Of surrounding space. They cannot
produce heat or set fire to any infiammable
material. They would, therefore, increase
the safety of houses from fire.
The fact that radium cannot ignite gas
suggests the great possibility of its intro
duction as a means OF lighting mines. But
az fits present price the half pound men,
toned as sufficient to light an ordinary
room would cost $500. Yet, If such a
supply would last a million years, a single
lamp, even at this price, would shine upon
thousands of generations and would more
than pay for itself in saving gas, oil and
electric light bills.
GILDED CITIES OF THE FUTURE.
When radium is cheaply and ~abundantly
produced 1t will be a simple matter to
illuminate our streets with globes coated
with it's radiant, film. Our watch faces,
similarly treated, will be visible in the
blacklist darkness. Ships gliding under the
inky canopy of night will. perhaps, be made
as brilliantly visible as the fiery vessels of
fairyland. There will be no more cropping
about in darkness for the house numbers
of our friends. A radiantly outlined key
hole will be a blessing to the late slayer at
the club. Wearing luminous apparel. the
pedestrian will. perhaps. reduce the risk
Of being run down in the dark streets by
the lightning-speed, noiseless-tired vehicles
of modern times, or the never-present po-
liceman will be conspicuously in evidence
when urgently desired. Perhaps our books,
our magazines, our newspapers, will yet be
printed In luminous ink, visible in darkness
as well as in light. What need of head
lights upon our bicycles, our automobiles,
our street cars and our railroad trains If
these space eliminators can be adorned
with radium paint? Who can gainsay that
the wonderful mineral will ultimately be-
come so cheap that country roads and by
ways can be lined with fiery fences. leading
the rural plodder safely on his dreary way?
And may not our very cities themselves
stand out from the earth's sable crust in
burning consultations, striking awe and
admiration to the Martians?
But, seriously, when radium can be foune
in abundance it will undoubtedly afford
man his cheapest light-a light which will
never fail.
JOHN ELFRETH WATKINS, JR.