Measurement of the two components of air earth conduction current in the tropics

Abstract

An attempt has been made for the first time at Poona {India) to measure both components of air earth current corresponding to the positive and negative ionic conductivities, To avoid electrode effect, at a distance of about 15 m above the ground, two duraluminium test plates (1 m square approximately) are being used one above the other separated by 20 cm. To measure the two components of air earth current, the top and bottom Plates are connected to the two pairs of quadrants respectively of a quadrant electrometer and the needle is connected to a steady battery of 22.5 volts. To avoid displacement currents due to potential gradient changes two radioactive collectors are used one for each plate so that the correction due to the displacement current is rectified at the plates themselves. Full details of measurement of the two components of air earth current using the above apparatus are given and their importance in the study of the various problems in atmospheric electricity has also been indicated.