What's the difference between seismometer and seismometry?
Seismometer
Definition:
(n.) An instrument for measuring the direction, duration, and force of earthquakes and like concussions.
Example Sentences:
(1) By now my controversy seismometer is going off the Richter scale: Muslims, Jews, Hitler – it's like a mass invitation to every irate commentator in the blogosphere.
Seismometry
Definition:
(n.) The mensuration of such phenomena of earthquakes as can be expressed in numbers, or by their relation to the coordinates of space.