The Wahpeton times., 1918-03-28

quadrangle mas recently been pub.
lished by the United States GeoloKi-
cal Survey.
= This map represents by far the
most complete survey ever made of
this section OF the state. It shows so
clearly every physical feature Of the
quadrangle that the character of any
part Of 1t. as we'll as the shapes of
the hills and valleys. can be seen at a
glance, and the altitude of any par
ticular point can be easily determined
The relief of the country is graphi-
lcally shown by means of brown con-
tour lines. each one of which rep
resents certain altitude above the
sea. The traveller walking along the
course shown by one of the contour
lines will go neither up hill nor down
hill but on level. That such a
map Is Of prime value to the engineer
who may be laying out railroad or
trolley route. highway, a drain
age or irrigation system goes with
out saying. but it is also of great
value to the average citizen. Far
mers and automobilists, for instance.
buy thousands of the maps. In adj
ditton to the land and water fea-
tures' the map shows. in black. all
the WORKS of man-roads. bridges.
towns, houses. etc.
The topographic mapping done by
the Geological Survey represents the
highest type of geographic work, and
the maps show substantially eyerv-
thing as 1t is on the ground at the
time Of the survey. In making the
survey for this particular man the
topographic engineers tramped over
practically every part of the quad
rangle. hundreds of miles being thus
covered. Permanent iron bench
marks. showing exact attitudes, were
also set at numerous points in the
quadrangle. The location of these
marks is indicated accurately on the
map and they can be used for all
time as the basis for any further
SURVEYS desired. Map making of this
sort is very different undertaking
from that of constructing the average
geographic map at adesk-generally
a matter OF mere approximation and
compilation. Everything on the
Geological Survey topographic sheet
is exact and true to nature.
This sheet forms but one small
section of the great topographic at
las of the United States, which the
Geological Survey is making and
which will be the largest and vet
the most detailed atlas in the world
When completed this map will be an
proximately an acre in extent. Al.
ready more than 2,300 of these
sheets have been completed. cover
Ing nearly AZ per cent of the United
States.
In some parts of the country much
of the work is carried through rough
and almost impossible areas. with
dense forests. insurmountable preci-
pices. or deep morasses. Hundreds
of temporary camps are made dur
Ing each field season, at attitudes
ranging from above snow line to be-
low sea level. All this work ia fol.
lowed by an enormous amount Of
office drafting. and the task is final
'ly completed in examples of copner-
plate engraving and lithoeranhic
printing second to no others in the
world. ~
The cost to the Government Of
these quadrangle surveys, for both
field and office work. ranges from
$4,000 to $4,000 each; but the mans
are sold at only about the cost of
paper and printing-10 cents a COW
or So for fifty copies.
The Director of the Geological
Survey will furnish without charge
index sheets showing the published
topographic maps of areas in any
State.