definition
A device used by seismologists to detect and measure seismic waves and therefore locate earthquakes etc; a seismograph.
On the next page, we will have a look at some example seismometer traces.
In the Wiechert astatic pendulum seismometer the stationary mass is also cheese-shaped, but it is supported by a conical extension from its base, which balances it on the floor of its case.
Wiechert has also constructed a seismometer on the same principle, but in which the stationary mass is smaller, being adjustable between 80 and 200 kilos (180 and 440 lb).
The term " seismometer " may conveniently be extended (and will here be understood) to cover all instruments which are designed to measure movements of the ground.