Readjustment of Triangulation Datum

The readjustment of the basic triangulation of the United States to the 1927 North American Datum created a problem to all organizations whose surveys were built on the basic system. Complete recomputation and readjustment being out of the question because of their prohibitive cost, the United States Geological Survey investigated methods of readjusting its earlier triangulation to fit the new datum by applying corrections to the old datum values. Since the corrections are usually very small, approximate methods of determination give reasonably precise results.