River Falls journal. [volume] (River Falls, Pierce County, Wis.) 1872-2019, 1897-12-30
OZARK LIGHT"
Many Substances Generate Rays That
Affect sensItiNe Plnfea.

Another startling discovery has been
made IN the realm of Invisible rays, and
independently verified by different ex-
perimenters, namely, that many sab
stances which we have been in the habit
Of regarding as inert are constantly
smi;tir g invisible rays In the absence
OF other light, which rays possess
actinic power and therefore are capable
Of affecting sensitive photogra
plates. Some six months ago the emf
nent French Investigator. Beequerel,
discovered that the element uranium
when exposed TO brilliant ..ght stored
up during this period energy whiCh was
either transferred iE.o rays Of ether
kinds or else emitted Ia lie or gnsl in
cident form, when the slostance was
placed In absolute darkness. Moreover,
these rays possessed remarkable pow
ers Of penetrating light, opaque sub
stances, Y rty like. Or. Russell IN a
paper recently read before the Royal
Society of London described how in
repeating Beequercl's experiments he
discovered that this particular action
is by no means confined to uranium
salts, but that many Of the metals and
other bodies, such as wood, charcoal,
copal, straw, etc, possess il ~ marked
legree. The radiations from these
bodies, however. differ in one very i'm
portant particular from those given out
by the uranium compounds. While the
latter readily pass through glass the
former are completely stopped by IL.
Starting with the metals. mercury
zinc, magnesium cadmium, nickel,
aluminium, pewter, fusible metal, bis
muth, tin, cobal; and anthony, he
found that all these, after a weeks eN-
posture near sensitive plate in the
dark, every precaution being taken TO
exclude extrancous light, produced a
distinct effect upon the plate, while
gold, iron and copper only showed a
very slight effect. The fact has been
known for long time that certain sub
stances when placed in contact with a
sensitive film for long time viii show
traces of their outline in the develop
ment of the plate. This phenomenon
has never been satisfactorily explained
/ Dr. Russell, results, however, are not
based on this principle, as in one in
stalce a polished surface of zinc with
design scratched on il gave distinct
image of the markings when not touch
ing the plate, and even when thin
screens of gutta percha or celluloid
were interposed between the sensitive
plate and the zinc surface. In another
set of experiments cardboard pill boxes
used for in-.osing certain substances
/ before the experiments, were found tC
be quite .iive themselves in emitting
these remarkable radiations. imprint
ing most distinct image OF themselves
Different qualities of cardboard giv'
varying results. The better kinds act
ed but family, while cheaper A.nds
such rs strawboard, were very active
| In the same way certain printing ink:
gave very good impressions on the
plate, while others were altogether
/ inert.
As regards the conditions affecting
| the emission of these radiations, it i
/ known that heat increases their activ
/ ity, and the water vapOr in no way as
siSts their action. Their source is
mystery. Some form of potential ener
gy stored up in the active bodies pos
sesscs the power of generating, through
what medium has not even been sur
missed, rays quite rs remarkable as tn,
| Roentgen rays, and possessing in lin
tied degree many of their characters
! tic properties. Probably their natur,
| is akin TO what has paradoxically beer
| styled, dark light. "-Chicago Chron
| iclc.