A New Type of Quadrilateration

In city surveys, the required primary control is obtained most commonly by a local triangulation scheme. In recent years, however, the great progress made in the field of electromagnetic distance measurement, which has resulted in improved and practical versions of both geodimeter and tellurometer systems, has made it possible to employ more flexible configurations of control nets than was possible with the classical triangulation method. One such new method, which is under study in Poland, is described briefly.