Evening star., 1925-08-20
CEILING Of SKY"
LOCATED BY NAVY
Discovery Expected to In
crease Range of Radio and
Reduce Operation Cost.

| Information expected to lead to de-
cided improvements in radio and
other wireless communication has
been collected by the Naval Research
| Laboratory here working in cooper
alton with the Carnegie Institution of
! Washington.
| Secretary Wilbur in announcing
the discoveries indicated that the
work would go a long way to elimi-
mating fading" from wireless COM
munication, and that it already had
been carried to a point where 1t
could be stated definitely that high
frequency transmitting station could
be built for about 100000 instead of
present stations which cost approx
mately $2,000,000.
| The new stations, he added, not
only would cost less, but also would
! give better service and longer range
and could be operated much more
| economically.
100 Miles Above Earth.
The investigation confirmed the
| theory of an ionized region in the
| higher levels of the earths atmos-
phere. The ionized zone was de-
scribed as constituting "a ceiling of
the sky" but additional research will
| be required to determine its size,
shape and exact location. It is, how
ever. known to lie more than a hun
dred miles above the earth.
From observations made" said a
Navy Department statement, "it ap-
pears that the plane of maximum
density, in popular language the cell
| ing of the sky, lies at a~varying dis
| tance above the surface of the earth,
| rising and falling as atmospheric
| conditions vary.
This layer, the conception of which
| originated independently with Heavi-
side in England and Kennedy in the
| United States, is known in the
scientific world as the Kennelly-H -Heavi-
| side layer. 1t acts as a DETECTING
surface to electromagnetic waves
| under which they are guided around
| the world in very similar way to
| that in which whispered sound waves
run under the domes of the Capitol
at Washington and of ST. Paul's
| Cathedral in London.
Measurements Made.
'The results attained are based upon
/ an analysis of the phenomenon known
as the sky distance checked by a
simple mechanical device by means
of which the effective distance Of the
DETECTING layer may be actually
measured.
I'm the pioneer work of short wave
| length transmission, it was the ex-
perience that signals could be picked
| up at distances of 40 or SO miles,
after which they disappeared. They
were again picked up at points hun
| dreds of miles distant. The inter
vening of dead space of non-reception
| became known as the sky distance,
In seeking to account for this. a
| theory was developed at the research
| laboratory that there was a relation
| between the earth's magnetic field, the
| frequency of the waves used, skip dis
| tances observed and the height of the
! Heaviside layer. This relation could
be and was worked out mathemat-
| ically, using data contributed bv
| the members Of the American Radio
Relay League and their co-workers
| in foreign countries.
| Find Wave Is Double.
THE joint experiment with the
| Carnegie Institution of Washington
| approached the solution of the prob
| lem from a different angle, demon.
strating definitely the existence of two
waves, one of them arriving by way
| of the earth and the other by way
| of the layer. From these expert
| ments estimates of effective height of
| the layer were made, these estimates
| being essentially in agreement with
| the estimates derived from observa-
| tions on the skip distance. Other
peculiarities of the action of the layer
have been investigated by the Car
negie Institution of Washington in col
| laboration with the Radio Corpora
| ton of America and the Westing-
house Manufacturing Co.
''The knowledge now gained will
play an important part in further ad-
vancing the radio art"