and that error will influence the final results for all other points obtained by that observer for the entire
day. When more than two check or tie points are used, the computer can usually discover a faulty check
point recording, provided an ordinary misreading is the apparent cause. Because of the different
conditions and circumstances under which a day's observations using any one altimeter are made, the
computing and adjustment of new elevations require good judgment on the part of the computer, and a
good knowledge of field procedure is helpful.
(6) Regardless of how carefully the adjustments and corrections are made, discrepancies will still appear
when elevations using altimeters are found for benchmarks or other points which have previously been
determined by higher order methods. When this is the case, the computer will have to adjust each
series of observed elevations in order to make them agree with the check or tie points. Comparable
corrections must then be applied to the elevations observed using the altimeter at new points which are
generally found in the series between check or tie points. It is assumed that such corrections are likely
to be influenced by various factors such as elevation, elapsed time, and horizontal distances. Between
two tie points which differ greatly in elevation it is probably
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