Evening star. [volume] (Washington, D.C.) 1854-1972, 1950-08-13

ruins. But for the past five years
the fear it inspires has been vastly
increased by the mystery which
has surrounded it., Fear Of the
unknown is the greatest fear man
knows and throughout history
ghosts and demons have caused
more terror than lightning or
hurricanes.
The atomic bomb from the be-
ginning has been considered more
as a demon than as a physical
fact and there has been more
or less paralysis in considering
possible defense measures against
it. To the people Of this country
it was. until quite recently, a
friendly demon. There persisted
somehow an egotiStic and silly
confidence that it was an Amerl-
can secret safe from any poten-
tial enemy except through mach
nations of spies and traitors.
All this quite in the face of the
fact that some of the most bril-
liant atomic physicists in the
world were on the other side.
Average Man Mystifed
For the average American it is
almost a complete mystery and
the man on the street seems will
ing to believe nearly anything.
This is due in part to the fact
that the forces involved, by far
the most stupendouS in creation,
are completely beyond his COM
prehension and outside his sem
sorry experience. The atom itself
is unreal, unbelievable. To a con-
siderably lesser extent it is due
to the policy Of secrecy about
atomic weapons, much of the need
for which has disappeared since
Russian nuclear physicists worked
out the whole thing independent
ly-perhaps aided to very in
consequential extent by the rev.
Citations of traitors.
At the best, the bomb is bad
enough. But at present it is not
as bad as the imaginations of i'll
informed alarmists can make it..
There still is much that can be
done to minimize its effects, de-
pending on understanding of its
mechanisms of destruction. From
the first it has been the policy of
the Atomic Energy Commission
to preserve as little secrecy as was
consistent with national security
and last night it went beyond
anything ventured before in TAX
ing the public into its confidence
on the mechanisms and effects
Of atomic weapons.
Clues TO Size
In the past the most vital secret
of all has been the size of the
bomb, for it must remain quite
close to certain critical dimensions
in order to explode at all. A little
smaller or little larger and it will
be a complete dud. The report is
sued last night may even make it
possible for any one with some
knowledge of nuclear physics to
calculate the dimensions. 1t states
bluntly that somewhat more than
two pounds of fashionable material
is used. This, of course, potential
enemies calculated long ago.
The effect of an atomic bomb
explosion are threefold. First
by all odds the most important
and probably also the least feared
because they can be most easily
comprehended-are the blast eff
fects. These are the shock waves
in air or water proceeding from
the great ball of fire which imme-
diateIy follows the bombs detona-
ton. They topple and crush what
ever is in their path. Within about
a half mile from the center Of the
blast buildings will be crushed like
eggshells and there will be vir-
tually complete destruction. Struc-
lures might be built which would
be fairly resistant to them, but
this would mean virtually rebuild
ing most cities. There is severe,
hut not complete. destruction over
an area of about four square miles
moderate damage over eight square
miles, slight damage over II square
miles and traces of damage over
approximately 200 square miles
The ultimate range depends great
w on nature of terrain and me-
neurological conditions on the DAY
of the explosion.
Scaling Laws Revealed
These are the estimates for the
type of bomb which was dropped
on Hiroshima and NagaSaki IN the
late summer of 1945. The extent
and range of destruction will be
increased with more powerful
bombs. such as now are believed to
be available, but there is not a
one-to-one correlation between
power and range Of destruction.
That is, an atomic blast equlva-
lent to the explosion OF 10000
tons of TINT will not have twice
the range-or anywhere near 1t
of the equivalent of 10000 tons OF
TINT. The report makes public
for the first time so-called seal
ing" laws, automatically some
what complicated although re-
duceable to simple formulas by
which the reader can calculate the
extent of destruction for himself.
But these blast effects are, after
all, the same kind of effects known
from the last wars INT block
busters" which became fairly ia
miliar to a good part of the popu-
Iation of Western Europe. They
differ only in magnitude. Famili-
arity rids them of their worst ter
rors.
The two remaining effects of an
atomic bomb blast are more ter
rifying because they are more
mysterious and men have had little
experience with them. First is
the heat effect. Within few
thousandths of second after the
explosion a great ball of fire is