Evening star., 1923-11-28

Last saturday evening. there was
intense interest amongst a group OF
scientists gathered about a banquet
| table at the Cosmos Club while q
distinguished recipient of the Nobe
prize for 1922. DIR. Niels Bohr, pro-
feSsor of theoretical physics of Copen-
hagen. was telling something of what
he had discovered about the structure
of an atom.
Later, when two of the leading
physicists of the United States bureau
of standards were asked to tell what
DR.. Bohr had talked about each de-
ferred to the other. Both agreed that
they understood it perfectly, but that
they had ever heard. For a physicist
to tell it to a layman was as difficult
as If Greek and a Norwegian were
to talk to each other, each in his own
laneuage. yet hoping to be mutually
intelligible
An atom! In school days, 1t was
taught that a molecule, the unit of
matter. was made up of atoms which
were the smallest conceivable indi-
visible units. A molecule of water
(HsO) consists of two atoms Of
away any one Of those three atoms
and the water ceases to be water. The
same atoms are found in other kinds
of matter, in combinations with 9TH
er atoms
Nobody ever saw an atom. No mi
croScope can make ii visible. Yet
within the last eight or nine years,
scientists have begun to compare an
atom with the solar system, with a
nucleus Infinitely small. about which
are speeding planets" at distances
from the nucleus, greater. in proper
ton to their size, than the distance
from the sun to the earth-greater,
even, than the distance from the sun
70 the farthest of planets. Neptune.
The atom, as a solar system" is
emptler than all the space in which
the earth and the seven other solar
planets revolve about the sun.
The sun may be taken as ball
nine feet in diameter; the earth, in
proportion, would be a marble one
men in diameter. lying three city
blocks away. The earth is about
100 solar diameters away from the
sun, but, according to DIR. Millikan,
an atoms "planet"-called an cleo
tron-is 10000 diameters Of it's
nucleus away from that nucleus
possibly 100000 diameters-and it is
revolving about that nucleus at a
speed exceeding 10000 miles a sec
ond. If an atom were magnified TO
three feet diameter its nucleus would
be mere pinpolnt, too small to be
seen two feet away.
DR.. Stratton, former head of the
bureau of standards, used to try to
illustrate the size OF an atom as
follows: Take spray of oil and
pick out the smallest oil Elobule
tloating in the air. Magnify that
globule until it is as big as the
world: the atoms composing II would
then be the size of little peas"
Now take one Of those little peas.
several planets" (eIectrons) speed
ing around orbits 10000 times as
great in proportion as Neptune s
orbit. and try to measure the orbit
accurately and to weigh the electron.
That is what has been accomplished d
of the Bridge Laboratory OF Physics.
At San Diego. Calf, and chairman OF
the administrative council of the
California Institute of Technology.
nr. Millikan has been awarded the
Nobel prize for physics for 1923. He
has not only seen" an electron. but
has timed its speed with his scientific
stop-watch. while the tiny planet"
was plunging through empty space
about it's sun" 10000 diameters
away.
Science can see more than fifty-six
times as wide range as eyes can
discern. DIR. Millikan, in an article
in recent issue of Scribner's
Magazine, shows a five-and- -one-half-
inch scale of the span Of discernment
on which the range of eyesight is
measured one-eighth Of an inch Be
yond the visual one-eighth inch on
the scale extend to the right ultra
violet rays occupying half an inch :
beyond are the Roentgen rays and
N-rayS measuring on that same scale