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Aristotle was the first to try to prove earthquakes wre made because of a natural cause. He stated that winds from the Earth occasionally shaking the Earth's surface. Before Aristotle people believed organisms lived under the ground. From those active organisms as people believed were the cause of earthquakes. Actual date is around the 350s B.C.
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Chang Heng created the Dragon Jar as a seismometer but it was so sensitive, and it can also tell which way the direction of the earthquake is coming from.
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The Elastic Propagation theory was developed and it explained primary, secondary, and surface waves.
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Seismographs are used to detect and measure strength of earthquakes and funds for seismology academies. It begins in the 1850s.
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The first seismometer ever to record the intensity, time, and duration of any movement was created by Luigi Palmieri in Italy. After the Mercury moves it creates electric current which can then be measured.
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Irish Engineer R.Mallet observes damage from earthquakes and concludes that earthquake waves come from a central focus and that if those waves are traced back the central focus can be found.
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Seismographs are used to detect and measure strength of earthquakes and funds for seismology academies. It ends at the 1860s.
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The San Francisco Earthquake of 1906 was recorded by the first seismograph to ever be installed in North America. That seismograph was installed at 1897.
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An American Engineer H.F.Reid made a theory in which elastic energy is released spontaneously by a slip on the fault.
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In the early 1900s B.B.Galitzen created the first electromagnetic seismograph into which is more accurate than other mechanical seismographs.
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Charles Richter creates the Magnitude scale so earthquakes can be measured.
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When most seismic stations were established after 1900s to lead that earthquakes happen only where crustal plates spread apart.
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The WorldWide Standardized Seismographic Network was established creating very reliable and high quality data set. This helped seismology advance very well.
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All modern seismographs that are used are electromagnetics
