@article{oai:nagoya.repo.nii.ac.jp:00019729, author = {竹内, 利雄 and 石川, 晴治 and 高木, 増美 and Takeuti, Tosio and Isikawa, Haruzi and Takagi, Masumi}, issue = {1-2}, journal = {空電研究所報告}, month = {Jun}, note = {We have obtained four sets of pairs of electrostatic field change records produced by ground discharges through the coincident observations at two places, Maebashi and Shibukawa, which are 13km apart. Though the number of data suited for the present investigation are only four, the following results have been obtained. 1) A pre-preliminary discharge was observed to have occurred at a place in a thundercloud, away from the portion just above the struck point on the ground. 2) The height of the negative charge of the concerned ground stroke was about 3 km in one case. 3) It has been found that the data of the time interval between the two successively recorded ground strokes are to be divided into three groups. The first group has the time interval of less than 600 ms and is due to stroke pairs each of which belongs to the same discharge. The second group has the time interval ranging from 600 ms to 3 sec, and seldom occurs. The third group has the time interval longer than 3 sec, and the interval corresponds to the recovery time of the negative charge dissipated by the preceding stroke of a stroke pair.}, pages = {27--29}, title = {雷放電の研究(第4報) : 二地点における落雷の同時観測の結果について}, volume = {11}, year = {1961} }