  The period of an undamped compound pendulum has been selected to maximize the
instrument's response to microseisms, when functioning as a type of horizontal
seismometer. When functioning as a tiltmeter, the instrument is also capable of
monitoring eigenmode oscillations of the Earth. Other instruments designed by
the author, some of which were monitored during hurricanes, suggest that storm
seismicity in the frequency range of this pendulum could aid the process of
hurricane forecasting.
