seismometer
(saɪzˈmɒmɪtə(r))
[f. seismo- + -meter.]
An instrument for measuring the intensity, direction, and duration of earthquakes.
All practical seismometers now record their observations automatically, hence the name is used almost interchangeably with seismograph (q.v.).
| 1841 J. D. Forbes in Edin. Phil. Trans. XV. i. 220 The self-registering part of the apparatus, which Mr. David Milne has termed a Seismometer. 1886 J. A. Ewing in Encycl. Brit. XXI. 626/2 Seismometer. This name was originally given to instruments designed to measure the movement of the ground during earthquakes. Ibid. 627/1 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. |