1 The inside of the seismoscope is unknown: most speculations assume that the motion of some kind of pendulum would activate the dragons.

2 The earliest seismoscope was invented by the Chinese philosopher Chang Heng in A. D. 132.

3 A seismoscope is an apparatus or device which only indicates that an earthquake has occurred.

4 The instrument is reported to have detected an earthquake 400 miles away that was not felt at the location of the seismoscope .

5 In 1703, Frenchman Feuille invented the first seismic instrument of Europe --- the mercury seismoscope ( Dewey, 1969).