Schlumberger electrode array, idea of apparent resistivity. Resistivity map of the May syncline. 1921 Telluric currents. Simultaneous recordings in Alsace. 1927 Variable line length electrical soundings.
Alsatian salt domes.
First tests of the torsion balance in Mantes, France. Perfection of terrain corrections at the Capbreton dunes in France. Growth of gravimetric and magnetic survey activities. V. Baranov invents the master curves for calculating the different components of the potential fields. 1929 Theory of electrical prospecting.