Evening star., 1942-06-27
Of Stars, Men
And Atoms
Notebook Of Science Progress
In Laboratory, Field
And Study
By Thomas r. Henru.

Apparently 1t already has existed about
fourth of its life span.
Such is the latest estimate of DR.. H. A.
Bethe of Cornell University, who first
propounded about five years ago the
carbon cycle" theory to account for the
titanic output of solar light and heat.
This seemingly has been going on for
! about 2,000,0000O0 years with no per-
ceptible change in amount.
The interior of the sun, DR.. Bethe
holds, Is like an enormous atom smaSher.
Temperature there is about 10000 900 de-
grees centigrade At such a heat all the
atoms are stripped of their electrons and
only the nuclei remain, rushing about
furiously and frequently colliding with
each other
Here is the theory as it now stands:
First carbon nucleus of mass l2-
that is II times the mass of hydrogen
atom-bumps into loose proton and
| captures it.
| It then becomes a nitrogen atom OF
mass 49, an unstable form which soon
| breaks up by shooting out a positive
| electron, or positron. The nucleus then
becomes carbon again, but carbon of an
unstable form. The positive electron
almost immedia tely unites with wan
dering negative electron and the two
disappear in a burst of energy.
The newly formed carbon nucleus in
! the course of time picks up another pro-
ton, thereby Transforming itself into a
nitrogen nucleus of mass IA. More en-
ergV is radlatcd.
This new nitrogen nucleus exists for
! several years but eventually picks up an
! other proton and becomes oxygen of
mass IS. This oxygen nucleus is itself
| unstable, throws out positron, and be-
comes nitrogen of mass Is.
This nitrogen in the course of about
! 20 years will be struck by hard-hitting
| proton and smashed. The result will be
| carbon of mass IL Just as it was at the
! start, and helium of mass T.
| All that can now happen is for the
! process 10 be repeated all over again
| Every time new form of atom is created
there is some energy left over to become
The whole carbon cycle requires about
100000 years. Every time it occurs a
/ little Of the suns mass is lost.
Robot SentrieS with ears so sensitive
| that they can hear whisper or the
| tUitter of a sparrow a mile away now are
| guarding plants Of one Of the country S
/ greatest industrial rorD0ratiorc
They would be equally efficient guards
! for any area which could be inclosed in
/ wire fenCe-such as an army depot or
| internment camp.
This type of mechanical sentry is an
| invention Of an engineer of the E 1.
| Gu Pont de Nemours & Co. and six
| months Of tests under every conceiva bic
| condition have proved it the most eff
! cient ever devised, company officials say.
! The mechanics Of the contrivance have
not been revealed. The fence itself acts
| as the ears Of the robot and re-
lays instantly to human watchman,
who may be stationed in a comforta BILE
watch station inside the plant. such
! sounds as the snip of wire cutter or
the sound of a pick.
The mechanical sentry, Du Pont en-
| gineers say. has the effect of multiplying
| BY many times the number of guards on
| duty in bad weather and at night.
| During heavy fogs, blackouts and storms
| guards would have to be placed almost
! shoulder to shoulder along fences which
| often are from Is to 20 miles long
p1I !,
only Of any disturbance, but of its loca-
| ton.
If necessary, the Du Pont engineers
! announce. they will overhear voices
! speaking in whispers. bird songs and the
! sound of wind blowing and transmit
| them for mile. Actually, however this
| Is more than is wanted and such delicacy
would defeat its own purpose. The sys-
! tenn is adapted to screen out such sounds
and pick up only those likely to be i'm
| portant.
In addition to extending the hearing
range Of guards. the robots provide a
| checklng-in system. A watchman need
only to step up to the fence and tap in
an established code. He will be heard in
| headquarters. He also can use the fence
| line telephone to call for help. The line
is always open.
The manner of receiving warning sig
nails or the guards calls can be as elabo-
rate as desired. They can be heard
through loudspeaker or can be made
to record themselves silently on a mov-
ing tape or drum, showing the exact
hour, minute and second received The
signals may also be arranged to ring a
bell or automatically relayed to military
or r,o1ico bao