World-first Earthquake Detector

A piece of powerful and useful equipment to measure earthquake waves.

The first instrument for recording earthquakes was built by the Chinese scientist Chang Heng in the second century. The original instrument did not survive, and we know of it only from descriptions of that time. It was a large bronze device about 6 ft across. It was designed to record earthquakes too slight to be felt and to tell roughly what direction the quake had come from. When the ball drops out from the dragon's mouth into the frog's mouth. It means that the direction has an earthquake. When this happens, a messenger will be sent out in that direction and rescue the situation We now call it a seismoscope.