The magnetic character of the year 1916 and review of the years 1906–1916

The annual review of the “Caractère magnétique de chaque jour” for 1916 has been drawn up in the same manner as the preceding years; moreover it contains a review of the collaboration of the observatories during the years 1906–1916.In 1916, 36 observatories contributed to the quarterly reviews; 35 of them sent complete data. Table II of the annual review, containing the mean character of each day and each month, the list of “calm days” and the days recommended for reproduction, is reprinted here. From the review of the years 1906–1916 it appears, that altogether 52 observatories have contributed to the “Caractère magnétique”; an observatory that has been removed is taken with the new one as one station (Potsdam‐Seddin, Irkoutsk‐Zouy, Tiflis‐Karssani, Baldwin‐Tucson, Zikawei‐Lukiapang).