Some microseismic tremors and their apparent connection with barometric variations

In 1874 Professor Rossi of Rome, in “Bulletino del Vulcanismo Italiano, Vol. 1,” called attention to a possible connection between microseismic motion and variations in atmospheric pressure. He stated that no marked barometric depression had occurred during the preceding three years without having been immediately preceded, accompanied, or followed by marked microseismic motion.2 Professor Rossi calls these effects baro‐seismic. The most recent papers on this subject, and the only ones to which I have had access, are those of Professor F. Omori, the well‐known Japanese seismologist.3 Professor Omori has called these motions “Pulsatory Oscillations”, on account of their regular pulse‐like nature.