Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1919-05-13

XXT ASHlNGIO4p u -, May T. u
wv gather by photography all the ma
terials for a map, including the ele-
vations Of hills and mountains, while lying
it in an airplane, will be possible within
Il few years in the opinion OF +. II. MoMlt,
OF the Geological Survey, who, together with
Major j. w. Bagley of the Engineer corps,
and j. B. Mertie also of the survey, has been
at work for many months on the use OF cam
eras and airplanes for map-making.
These scientists are developing method
Of making accurate maps, by photography
from an airplane, Of all features which show
in the horizontal. That is, they can now
make a map which will show the streams
and lakes, the roads, railroads, forests, and
Cities but which will not yet show the ele-
yations in any distinctive or reliable way.
They have, however, among other devices
with which they re experimenting, an in
which makes it possible to work out the ele-
walton from two overlapping pictures taken
from different points. While this method
has not been used except eXperimentally, it
promises to be one means of solving the
problem of topographic mapping from the
air 1t is also possible to supplement the air
plane map by a panoramic picture of the
same piece of country, from which the ele-
vations may be obtained by method which
Major Bagley has perfected.
The Importance of this use of the camera
and airplane in mapping can scarcely be
exaggerated. To the government alone it
will be invaluable. The Geological Survey,
the Coast and GeOdetic Survey, the Forest
Service and other branches OF the govern
ment doing field work, spend thousands Of
dollars every year in making maps. Until
few years ago this entailed going into
the country, and laboriously mapping the
topography of the plane-table method-Work
requiring much time and fit weather. Major
Bagley, as a member OF the Geological Sur
vey, more than doubled the amount of work
h. do in INV hn of 10
panoramic camera. He had still to go into
the country and scale the high points. but
the camera did in a second what would have
required half day with a plane-table.
The scientists had long seen the POSSIBLE
tiles of the airplane for this work, but the
instrument was not, before the war, suf6-
GENTLY perfected for their purses. Now that
the plane has become stable and reliable
craft, the inspiring possibility, opens up of
mapping the wild mountain regions of Alasak,
for example, with detail and accuracy, while
passing over them at the rate of a hundred
miles an hour This will be as far removed
from the method Of the old-time top0grapher.
toiling through the wilderness with his DAD
OF inlruments as tie automobile is from
the OK cart.
War gave the impulse which brought
about this development in mapping methods.
When things were at their worst in Europe,
and an invasion of America did not seem
ar impossible contingency, Bagley and Moi
fit were impressed by the fact, already real
lied by military authorities, that our At
lantic coastal country, from the mouth of the
Potomac clear around to the Gulf of Mexico,
was an unmapped country, much CT it wilder
ness. Wireless stations might have been
(and possibly were) established in this coun-
try, while it's unknown creeks and bayous
offered every possible advantage to an in
vading enemy.
What was needed was a method of map
ping this country with accuracy in very
short time. There was only one way OF do
inc, this-from the air. Bagley and Mofft
brought their work to the attention of the
Council of National Defense and received
an appropriation COR carrying it on Later the
engineer corps, to which Major Bagley be-
longed, took up the method SO that the work
became a cooperation between the Geologi-
cal Survey and~the corps of engineers. 4.
With these funds Bagley and Mofft built
their airplane cameras and their "rectifying
cameras, and carried on their experiments.
A panoramic camera and the ingenious in
strument by which he reduced his pictures to
maps, had already been designed and con-
structed by Major Bagley.
AS test of the apparatus, General Black