At Bombay thunderstorms invariably move overhead in some east-west or west-east direction according as they are “heat” thunderstorms or “line-squall” thunderstorms. Lln analysis has been made of the charge brought down by rain during the passage of 23 thunderstorms over Bombay in the years 1930-32. During 1930-31, nine thunderstorms transferred to each sq. cm. of ground 0.52 E.S.U. of positive charge and 0'75 E.S.U. of negative charge, and during 1931-32 fourteen thunderstorms transferred to each sq. cm. of ground 0.59 E.S.U. of positive charge and 1.46 E.S.U. of negative charge. Therefore, the 23 thunderstorms, collectively transferred t o each sq. cm. of ground 1.11 E.S.U. of positive charge, and 2.22 E.S.U. of negative charge. Estimating that an area of (100 km.)2 received charge at the rate recorded at Bombay, it is concluded that on the average each thunderstorm transferred to the ground an excess of about 2 × 103 coulombs of negative electricity.