Abstract
THE last publication of the Earthquake Investigation Committee of Japan contains five papers illustrated by twenty-six plates, ali of which are the work of Dr. F. Omori. The first of these refers to a horizontal pendulum tromometer, which is essentially a conical pendulum seismograph carrying a load of 50 kg. and writing indices with a multiplication of 120. In addition to recording earthquakes, it indicates the almost continual existence of “micro tremors,” the periods of which are about 0.3 second and the range 0.13 mm. When “pulsatory oscillations,” which are a larger form of disturbance than the tremors, are in evidence, it would appear from the illustrations, which are given of these movements that they might, seriously interfere with the character of an earthquake record.
Article PDF
Rights and permissions
About this article
Cite this article
Seismological Notes . Nature 67, 619–620 (1903). https://doi.org/10.1038/067619a0
Issue Date:
DOI: https://doi.org/10.1038/067619a0