Laurel outlook., 1946-03-27
Shell Action Is
Seen by X-Ray
Radio Specialists Shown
How Shrapnel Breaks
Bone Without Contact.

NEW YORK. - Pictures OF a
pressure wave breaking a bone, of a
supposedly armor-piercing shell de-
feating it's own purpose, and of anti
| personnel bombs in the act OF ex-
ploding, e shown to members OF
| the Institute of Radio Engineers at
its meeting here, says the Herald
| Tribune.
The pictures were taken with an
x-ray machine that a operate in
one-millionth of a second-20,0 900
times faster than a blink of the
average eye. The machine was de-
veloped before and during the war
by DR.. Charles M. Slack, assistant
director of the lamp division re-
search laboratories of the Westing-
house Electric corporation, and DON
aid c. Dickson, a Westinghouse
research engineer. 1t was used ex-
tensively during the war by army
and navy ordnance experts and by
scientists working on the atomic
bomb.
Pressure Wave Breaks Bone.
One of the uses to which the ma
chine was put helped to solve the
wartime mystery of how a small
piece of shrapnel can break a hui
man bone without touching it. The
leg of a small animal was placed
before the machine, a tiny piece of
shrapnel was shot into the leg, and
the picture was taken at the prop
er moment. Although the shrapnel
stopped in the flesh some distance
short of the bone, the picture
showed a pressure wave sent ahead
of the fragment with shock enough
to break the bone.
The machine was especially use
full to ballistic experts, who were
able to study the behavior Of bull
lets and shells moving through the
muzzles of guns, in flight, or strik-
ing targets. The story of the frus-
trated armor-piercing shell was
shown in slides recently by Mr..
Dickson. Pictures taken by the swift
x-ray showed the armor-piercing
cap breaking from the shell under
the impact of firing, followed the
two broken pieces in flight, and
caught the main body of the shell in
the act of catching up with and
SCATTERING the cap.
Tells Peacetime Uses.
Mr.. Dickson, who read a paper
prepared by DR.. Slack and him
self, said that the peacetime uses
of the x-ray device include the study
of machinery used in refrigeration
and electric appliances, and in arc
welding. X-ray penetrates smoke
and flame, and pictures may be
taken of the rapid transfer of metals
during welding, he said. The heart
of the super-speed machine, he ex-
planned, is a tube designed especial
ly to jerk electrons out of a cold
metal cathode at a rapid rate when
a high monetary voltage is applied.
A vacuum metallic arc is created,
supplying the electrons which
crash into the anode at 100, 900 miles
per second, pouring an x-ray bar
rage through metal to make the
SApOSuIS.
Other technical papers read dur
ing the final session included
on the development of a system for
radio transmission of instrument
readings in radio-controlled aircraft.
The system, known as radio tele-
metering, was explained by David
w. Moore Jr. of the Fairchild Cam
era and Instrument corporation. 1t
consists of magnetic devices which
may be fitted over dials on the in
strument board of the remotely con-
trolled plane or missile to transmit
continuous readings over conven-
tional radio equipment to the re-
ceiver, which may be mounted in
another plane or on the ground.