Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1904-05-06
Radium and Its Mysteries.


pardon me even if it is again told; for it
forms the first chapter in volume of
which many have still to be written.
NJ. Henri Becquerel prompted by a
hint from the celebrated mathematician,
NJ. poincare, discovered that the COM
pounds of uranium, somewhat rare
metal, as well as the metal itself, were
capable of imprussing a Photographic
plate wrapped up in black paper or other
wise protected from light 1t was also
found that such salts, placed near a
charged clectrosCupc, discharged it, the
gold leaves falling together An cleo
troscopc, it may be explained, is metal
box with glass sides; through a hole in
the lid "a wire passes. The stopper which
closes the hole and supports the wire
is made of sulphur or scaling wax, or
some other material which does not con-
duct electricity. From the end of the
wire are suspended two pieces of gold
leaf. hanging down so as to be visible
through the glass sides of the box.
If piece OF scaling wax is rubbed, so
as to excite it electrically, and if the pro-
jccting end of the wire is touched with
the rubbed sealing WAX "A small charge
of electricity is given to the WIRE and
through it to the gold leaves, 50 that they
rcpel each other, and fly apart, making
a figure like an inverted V. If the wire
be touched with the finger the electric
charge is conducted away through the
body, and the leaves swing back into
their original position
This effect OF discharging was found
to be produced when salt or mineral
containing uranium was placed inside
the box. Nine. Curie, a Polish lady,
living in Paris noticed that the rate at
which the gold leaves fell together was
more rapid with certain uranium min
erals specimens of pitchblende) than
could be accounted for by the uranium
oxide in the mineral; she therefore sep
tod 81 Al I'M a if- of.
stituents uranium, iron, lead barium,
bismuth etc. Cfor the mineral contains
all these and many other elements), and
tested each group as to its power Of dis
charge. At first she thought that she had
traced the discharging power to the bis
muth group. and attributed it to an ele-
meut which she named "polonium,' after
her native country.
This discovery has been dsproved but
It appears that the amount of polonium
ubtainablc is exceedingly small and diff
ficult to separate from bismuth. Suisse
queuuy Nine. Curie discovered another
element of the barium group, possessing
enormous powers Of discharge, and to
this element, which occurs in relatively
greater amount, she gave the name ''ra-
| dunn
It is an uudoubted element in the sense
/ i'm which that term is generally used; its
salts resemble closely those of barium.
and its spectrum has been observed hy
/ NJ Dcmalcay. Prof. Ruugc, and Sir VIII
/ liam Crookcs. Its atomic weight has
| been determined by Nine, Curie as 20
| the atomic weight of uranium is the high
est kuown-240. and there is some evil
dcucc from its spectrum that radtum may
! have even higher atomic wcight-OVcr
/ 25U-aud that the sample analysed by
/ Nine. Cuiic may not have been quite free
from baiium, of which the atomic weight
I is only 1877.
! While these researches were in prog
rpss NJ Curic and Dr. Schmidt discuN -
/ cred simultaneously that another element
thorum. of which tie atomic weight is
/ -. also Possesses the power Of discharg-
ing an olectroscup,. and, moreover, that
il air be- led over stlts OF thorium. Ia,
air acquires and retains for a short tim,
diScharging power
The subject was taken up by Prof
Rutherford. OF Montreal and 10y Nj. Fred
crick Soddy, who then worked in his lab
oratory: and they found that if the "ac-
tive" air were cooled with liquid air il
lost its activity" the active portion re-
naming in the cold tube ON warminl
the tube the active portion was carried
forward. and with it the discharginl
power They also found, that simila
Termination" or gas was evolved from
salts of radium possessing much more
permanent discharging power Will
| the "emanation'' from thorium salts de
cayed' in a few minutes. that from IA
dunn salts lasted a month. It, too, wa
condensible when cooled; it was lumi
nous, and impaired temporary lumin
osity to objects which it touched eek
cited activity'D.
The fact that n radium salt is Away
hotter than its surroundings discovere
by the Curies. implies that radium
, continually losing energy; and II the ra
l dunn salt be dissolved in water some q
this energy is expended in decomposing
! portion OF the water into oxygen an
/ hydrogen gases. Prof. Rutherford an
! H. T. Barnes have recently shown tina
more than two-thirds of the heatin
} effect is not due to the radium at all. bu
to the radioactive emanation which
produces from itself" In NoVembe
1902. Mcssrs Rutherford and Soddy con
3 cludcd from their experiments on the EN-
. anations from radium and thorium tina
e they are inert gases analogous in M
70 ture to the members Of the argon fam
o Uv" and also they threw out the SUI
o. mise whether the presence OF heliui
e i'm minerals and its invariable associate
= with uranium and thorium may not
. connected with the radio-activity"
70 Now. | had the good fortune to di,
e cover helum in 1895: it is one of the al
V gon gases. and is contained in certai
= minerals. and when Mr. Soddy came
5 work with me in the early summer
1903 we tested the truth of this surmis
and We were rewarded by success. II
II fresh emanation from radium does N
- show the spectrum of helium, but as
. DECAYS" helium is produced in mimi
II hut eyer-increasing quantity
= We can helm ourselves by an analog