the differences in elevation between the base station and the unknown points depends.
c. After the initial reading has been made, and the time, temperature, and humidity conditions have been
recorded, the field instruments may be transported to any of the other points (within 10 miles of the base station) for which
elevation reading are desired. Observations of indicated altitude, time, temperature, and humidity (wet and dry bulb
readings) are made at each point and recorded. During this period, the base station altimeter is read at five-minute
intervals, and all changes in weather conditions are noted and recorded. During the point to point traverse, readings may
also be taken of other known points of elevation to maintain a running check upon the readings being taken at each point
in the scheduled run. These checks are particularly desirable when they can be taken near the points in the scheduled run
which are most distant from the base station.
d. After all desired points have been traversed and observed, each instrument is returned to the base station for
the final observation of altitude, time, temperature, and humidity. This final observation must be taken with the same
accuracy as the initial observation, and since it is taken at the base station, it is desirable for the work to be arranged so
that a loop or circuit is formed by the points in the run. The circuit should be arranged so that not more than four hours is
required to complete the run.
e. During the run, any standard level or transit notebook may be used for recording the field notes,
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