Evening star., 1937-05-30
u. S.PH0TOCRAPHS
THIRD OF SURF ACE
Biggest Picture-Taking Job
in History to Aid Farm
Agencies.
By the Associated Press.


The biggest picture taking Job in
history-more than 100000 worth
Of photographers now under way
with Government agencies footing the
bill.
The subject of the photographs is
about one-third of the entire land
surface of the United States. Cam
eras do the shooting to miles above
the land from powerful airplanes.
Experts piece these photographs to-
gether and the result is a con- bina-
ton picture and map OF the land be-
low.
With these picture maps, Federal
ofhcials check the acreage and fields
of every farm seeking benefit pay
ments; plan soil conservation or pub
lie works projects; lay out parks,
dams, canals, drainage bitches, roads
or forests; or improve national de-
fense plans.
Aerial mapping is a development
OF the World War that has been per-
lected and improved for peace-time
purposes. This year many Govern
ment agencies are making wide use
Of the method.
The Agricultural Adjustment Ad-
mlnlstratlon, which operates Federal
farm programs, has called for 35O,OOO
square miles of air mapping In "a
States.
Soil Conservation Work.
The Soil Conservation Service let
contracts for 1920 square miles In
A States to provide basic maps for It's
battle against duststorms and wind
and water erosion.
Smaller projects are under way or
have been completed by the Army,
Navy. Resettlement Administration,
Tennessee Valley Authority, Coast
and Geodetic Survey, Forest Service,
Geological Survey and the Bureau Of
Biological Survey.
E. L. Deal. an A. A. A. executive
whose first contact with aerial map
ping was as World War captain,
said wide use Of the picture maps
was "a natural development because
they are better and cheaper"
1t costs from to 10 cents to sur
Vey and map an acre OF farm land by
former methods, he said. while aerial
maps cost about % cents an acre and
can be used longer"
Deal said pioneers in the aerial map
ping were corporations with oil, gas
and tlmberland. He said the A. A. A.
obtained some Of these picture maps"
Tor experimental use in checking farm
acreage in 1884 and then contracted
Tor mapping on small scale in 1895
and 1886.
high degree of skill is required
for the pilot and photographer in an
airplane 10000 to 10000 feet above
ground. They often fly over a strange
territory and must avoid tilt. wind
currents and other hazards TO obtain
good set of accurate prints. Veteran
mapping airplanes have covered 300
10 600 square miles in a day when
weather conditions were perfect.
Photo Of Entire State Possible.
Deal said it would be possible to
assemble a photograph of an entire
State-or even the whole United States
by. piecing negatives together if
floor space could be found large enough
for the job.
Ordinarily about III square miles
are shown in an enlargement used by
the A. A. A.
When the enlargement Is completed
q ground measurement is made of a
road or side Of farm to establish the
relationship between actual distances
and the picture map. Then a precise.
measuring instrument that looks like
a fountain pen with some wheels on
1t is placed on the picture map to
obtain distances. These instruments
are called planimeters and rotometers.
Deal said many new uses for the
picture maps were being developed.
Some agricultural experts expect them
to greatly improve accuracy of crop
yield statistics and estimates. Farmers
and county agents have used them to
make adjustments in field and building
plans on individual farms.
Ofhcials said many farmers asked
for copy of the photograph showing
their farm, to be framed and displayed
in the farm home.