The Black Hills union and western stock review. [volume] (Rapid City, S.D.) 1904-19??, 1908-12-18

series or years. ms part OF the
work is in charge of the Water Re-
| sources Branch of the U. S. Geolog-
| ical Survey, and is prosecuted as
rapidly as small appropriations will
| permit
A topographic map also shows,
without the necessity of prelimin-
airy surveys, the most feasible
grades and routes for projecting new
railroads. New Roads may be laid
out accurately with a small amount
of work. The travelling men and the
automobiles are glad to have these
maps, as they show the most direct
and safest routes from town to town
without inquiry.
In fact, today the first essential
of any enterprise is a topographic
map, whether it be the construction
of railroads, the irrigation of arid
lands, the building of highways, the
storage Of water, numbering or min
ing.
In order to make clear the scope
of the Topographic maps of the U. S.
Geological Survey the various items
that enter into their composition are
enumerated. They are printed in
three colors. In black is shown the
culture, which includes buildings,
trails, maps, railroads, county and
state boundaries, section and town
ship lines where they exist, bench
marks, triangulation stations and
mines, as we'll as all lettering In
blue are shown the drainage feat
ures, such as streams, lakes, rivers,
canals and glaciers. The hill and
mountain features, or elevations,
are shown by means Of contour lines
in brown. The contour intervals
varies with the scale of the map and
the relief of the country-where
they are close together the country
is steep; where further apart, gently
rolling, ETC.; and where none exists
the country is practically fiat.
The areas selected for survey are
defined by lines of longitude and
latitude and are called quadranglas,
which are named after the most
prominent city or natural feature on
the same.
AS permanent monuments copper
bolts or brass tablets, marking the
exact geodetic positions, of primary
triangulation points, are left at the
most conspicuous points throughout
the state where surveys are in pro-
gress. These monuments serve as a
base for all other government, pri-
vate and cadestral surveys. There
are also established permanent
figures the elevation above the mean
sea level. These serve As 4 datum
for future spirit level work, for en-
gineering Investigations and for
such public works as canals, rail-
roads and other public and private
surveys.
The making of complete topo-
graphic map of South Dakota was
begun by the U. S. Geological Sur
vey in 1891, and since that time
about 1854 square miles have
been surveyed, or approximately 90
per cent of the area of the state,
which is 1860 square miles. The
quadrangles covering this area
which have been or are in the course
of publication are the Glendale,
Columbia, Worthwhile, Aberdeen,
lRedfield, Byron, Huron, DeSmet,
Mitchell, Alexandria, Olivet, Parker,
Canton, Elk Point, Belle Fourche,
Redwater, st. Onge, Willow Greek,
Vale, Deadwood, Spearfish, Sturgis,
Rapid, Harvey Peak, Hermosa, Edge
mont and Oelrichs.
These maps may be obtained from
the U. S. Geological Survey at Wash
ingtOn, d. c., at the nominal price of
five cents per copy, or $500 per
hundred