A general view of the experimental field as it appeared on May 8, 1918, is shown in Figural. After the 1918 crop was harvested, measurements of the charge carried by the wind were undertaken. A ﬂame collector was used, which was connected to the gold leaf of an electroscope, the case being grounded. A full-scale deﬂection of 25 divisions represented a potential of about volts. 'in all the measurements the collector was held at a height of 1 meter above the ground.