Evening star., 1937-09-09
STARS, MEN AND ATOMS
Notebook of Science Progress in Field,
Laboratory and Study.
BY THOMAS r. HENRY.

Efforts to enter the weird world of
absolute cold were described in papers
presented before the American Chemical
Society this week.
1t is approximately 445 degrees Fahren-
heit below zero. Science has come to
within one-hundredth of one degree
from which vantage point it can overlook
the promised land which it never can
enter.
Absolute cold is complete absence of
heat. Heat is a manifestation of the
movements of atoms. Where all move
ment of the atoms within molecules stops
there is no heat and consequently 1t
cannot possibly be any colder Four hun
dred and forty-five degrees below zero
is one of the irreducible absolutes. Minus
four hundred and forty-six degrees is a
step beyond nothing. 1t is a contradic-
ton in terms, like "noisy silence"
There is, after all, lot of movement
and lot of heat in a cake of ice. The
hydrogen and oxygen atoms in its mole
cules are vibrating back and forth like
drunken dancers. There is still heat until
they can be made to stand absolutely mo-
tionleSs. This is admittedly an impoS-
sible goal. One can only get within an
infinitesimally tiny distance Of it, at great
cost.
Laboratories all over the world are
striving to get a little nearer to this
absolute There efforts are not stunts,
but potentially of great theoretical and
possibly practical Importance because
queer and largely ineXplicable things
are found to happen on the edges of
zero. The most notable is the change
in the phenomenon of electric conduc-
tivity. Through rings of such elements
as lead, tin and mercury an electric
current, once started flowing, will flow
on forever with no loss of power
If actual use could be made of such
a super-conducting metal in transmits
sion lines and electrical machinery the
effect would be revolutionary, but un-
fortunately the property disappears once
the temperature arises to within 20 de-
grees of absolute cold.
In paper presented before the So
ciety by DR.. H Grayson Smith of the
University of Toronto an explanation of
this phenomenon of super -conductivity
was attempted. Experiments indicate,
he said, that the entire piece of metal
becomes similar to one enormous mole
cule. Ordinarily electrons within the
metal are considered to be in more or
less random motion like the molecules of
gas, but in a super r-conductor it seems
that this electron gas must be solidified.
These electrons are the conductors of
electricity. When in a state of random
motion they are forever humping into
each other and losing energy. When they
are forced into straight line r otion by
the extreme cold they have always a
clear road
One difficulty with low temperature re-
search in the past, it was explained by DR..
D. H. Andrews of Johns Hopkins Uni
versity, has been the intricacy and cost
OF the apparatus necessary. Consequently,
experimental work has been possible only
at few centers. Recent developments,
he sald have simplified the apparatus
and reduced the costs to within few
hundred dollars so that this type of ex-
perimentation can be carried on in MANY
places.
AS we approach nearer and nearer to
absolute Zero" said DR.. Andrews, I'VE
may expect to obtain much more funda-
mental knowledge of the nature of mat
ter. electricity and energy. 1t is impos-
sible to predict what new and strange
phenomena may be discovered. Be-
SIDES this, the accumulation of the more
familiar types of data such as super
conductivities, specific heats, refractive
indlces and the like proves to be a very
valuable aid in the application of phys
ical theory and especially thermody-