PACIFIC SECTION OF TOPOGRAPHY. 
R. U. Goode, Geographer in charge. 
ARIZONA— CALIFORNIA. 
TRIANGULATION STATIONS. 
During the fall and winter of 1D02-3, Mr. R. B. Robinson extended 
a system of quadrilaterals down the valley of the Colorado River 
from the vicinity of Needles, Cal., to Yuma, Ariz., a lineal distance 
of 175 miles. Forty stations were occupied and 24 located by inter- 
sections. This work depends upon stations in the expansion of the 
secondary base of the United States Coast and Geodetic Survey near 
Needles, and a check was obtained by connecting with stations Pilot 
and Azimuth of the United States and Mexican Boundary Survey 
Commission near Yuma. Positions are given on the United States 
standard datum as derived from the transcontinental belt of the 
Coast and Geodetic Survey through the secondary triangulation along 
the California-Nevada boundary line from Lake Tahoe to Needles. 
A few of the stations in the vicinity of Yuma were selected, built, and 
occupied by Mr. A. II. Sylvester, topographer, earlier in the season. 
Arizona. 
CONE, MOHAVE COUNTY. 
A sharp, rocky peak, well known as "the Boundary Cone," about 
17 miles northeast of Needles, Cal. The road to Kingman via the 
Snow Ball mine passes by the base of the peak. To go to Cone from 
Needles, take road to Snow Ball mine, past the Cone. Stop at the 
first big wasl i road crosses after passing the peak and go up the wash 
a short distance — the best and perhaps the only way up. Horses can 
not be taken much farther than the wash. There are several springs 
within 2 or :> miles of the station and plenty of water at Leland mine, 
about 3 miles a little west of north. 
Station mark: A bronze triangulation tablet wedged in solid rock, 
about 2 inches underground, under center of a cairn 7 feet high. 
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