Abstract :
Earth connections in electric circuits are frequently made by driving a gas pipe into the ground. Such grounds are of fairly high resistance, and therefore not permissible where a low resistance ground is required. Their great simplicity and cheapness makes them desirable, where very low ground resistance is not necessary, as for discharging static charges, earthing overhead ground-wires, etc. To get data on the resistance offered by such gas pipe grounds, their permanence, and the variation of the resistance with the seasons, an investigation was started two years ago.