James G. A Manual on Ground Resistance Testing

Philadelphia: PHILADELPHIA ELECTRICAL & SCIENTIFIC, 1947. This Manual is intended to serve two purposes:
1. As instructions for the use our «Megger» Ground Resistance Testers;
2. As an introduction to the general subject of ground resistance measurements.Nature of a ground connection.
The single-test "megger" method for testing grounds.
Direction for using the "megger" ground testers.
Location of reference grounds.
Ground resistance curves.
Various methods for testing ground resistance.
Theoretical value of resistance to earth of a ground connection.
Current distribution and equipotential lines of earth.
Geophysical prospecting.