Notice of magnetic disturbance during eruption of Mont Pelée, Martinique

On May 8, 1902, at 11.59 A.M., Greenwich mean time, a magnetic disturbance occurred which began simultaneously at the two Coast and Geodetic Survey magnetic observatories in the United States, viz: at Cheltenham, Maryland, and Baldwin, Kansas. Taking the longitude of Mont Pelée, Martinique, as 4.04.6 W. of Greenwich or of St. Pierre 4.04.7, this magnetic disturbance began at 7.54 A.M., St. Pierre (or Mont Pelée) local mean time. The newspaper reports, in general, agree that the first eruption of Mont Pelée occurred at about 8 A.M. May 8th and it has been reported that the town clock of St. Pierre was found stopped at 7.50. The reports received thus far from other observatories, viz: Honolulu (Hawaiian Islands), Toronto (Canada), Stoneyhurst (England), Val Joyeux (France), Potsdam (Germany), and Pola (Austria) show that this disturbance was quite general, and that it began practically simultaneously at all of them. The horizontal intensity was the element principally disturbed.