b. With regard to permanence of monuments, no one can accurately predict what changes will
occur at a given site over a period of years, but it should be taken into consideration during the site
selection. You can be certain of a few things. All main roads will be widened, the grades will be
reduced, and the curves will be eased. Most cities will continue to expand. Suburban areas will be
enlarged, and residences will be built on what is now farmland, prairie, or wooded areas. All main-road
intersections are desirable sites for gasoline stations and other establishments catering to the motoring
public and should be avoided as station sites.
c. The right-of-way fence of an established highway is a good location for a station site, provided
the road is full width. Since triangulation stations are naturally placed on high ground through which the
highway may pass in a cut, it is necessary to keep back from the centerline. On the other hand, most
railroad property is fairly well established and the right-of-way lines are permanent with the exception
of abandoned branch and electric lines.
d. Cultivated land provides a fairly safe location but involves probable damages to crops each time
the monument is used and precludes the use of a surface monument. Some landowners will permit the
use of a surface monument on cultivated land. Never take advantage of such permission--at a later time,
new owners may think differently. Line fences between farms are often good sites for stations, and
signals can easily be built over them. Fences between fields are seldom permanent and are frequently
removed for tractor cultivation.
e. In intensively cultivated sections, some of the best sites are in the vicinity of farm buildings or in
groves maintained for shade and wind breaks. The buildings are generally located on knolls or fairly
high ground. Public parks and buildings and the grounds of city and consolidated schools are generally
in permanent locations.
f. In mountainous country, the natural physical conditions usually determine the permanence of
monuments. These conditions include the quality of the rock, the amount of frost, and the rapidity of
erosion. The tops of sand hills are often blown away, or blow pits, which may be started by the
monument itself, may engulf the monuments. If it not possible to avoid such localities, use a long iron
pipe monument.
g. During the final selection of station sites, it may be necessary to accept a weaker scheme in order
to obtain a better station site, or vice versa. Good station sites are important, but the strength of figure
must be maintained within the prescribed limits.
h. Accessibility is important both for the party establishing the station and all subsequent users.
Unfortunately, the most accessible sites are often the most exposed, and the ease of access is less
important than other conditions affecting the probable life of the monument.
i. The reconnaissance party assigns a name to each station selected in order to identify it and to aid
in its recovery. Although the triangulation party is
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