noun
definition
An instrument that automatically detects and records the intensity, direction and duration of earthquakes and similar events.
Examples of seismograph in a Sentence
The Richter Scale uses a seismograph to measure seismic waves.
Consider a second seismograph reading, this time from a station at Puerto Princes.
The first Professor of Engineering was James Alfred Ewing, a native Dundonian who invented the continuous seismograph.
Figure 4. Locations of temporary seismograph stations (red squares) deployed around Manchester.
Earthquakes (not of a violent character within recent centuries, though the ruin of the Colosseum is probably to be ascribed to this cause) are not unknown even at the present day in Rome and in the Alban Hills, and a seismograph has been established at Rocca di Papa.
For local earthquakes it will move relatively to the pivoted balance weight like an ordinary bracket seismograph, and for very rapid motion it gives seismoscopic indications of slight tremors due to the switching of the outer end of the boom, which is necessarily somewhat flexible.
The Strassburg or Bosch seismograph differs from those just described in resembling the Milne instrument, it is a horizontal and not a vertical pendulum.
The Galitzin seismograph, devised by Prince Galitzin, is of the same type, but it essentially differs from the Milne instrument in having its pendulum dead-beat; this is brought about by an electromagnetic device.