A FEW days ago I received from Prof. Milne a letter, dated March 15, 1895, in which he sends me a list of earthquake disturbances, compiled from the records he was fortunate enough to rescue from the fire which destroyed his house on February 17. In this list I find no less than three observations of the great Argentine earthquake of October 27, 1894, which was recorded by three different horizontal pendulums. The times given for the beginning of the earthquake—viz. 18h. 0m., 18h. 5m., 17h. 41m.1—are not very trustworthy, because they were determined by measuring the linear distance from a break in the curve which was caused regularly every day about noon by taking away the lamp. The exact times of these breaks were noted in a book, which, unfortunately, was destroyed by the fire. Prof. Milne, however, tells me that in the instrument, to which corresponds the first of the above-mentioned times, the lamp was always removed within half a minute or one minute from noon (Japan time). Consequently, the error cannot exceed a few minutes. The duration of the disturbance was between two and three hours in all the three instruments.