Yikyū Shionoya

A forgotten Japanese polymath who created the world's first earthquake prediction system in the Edo period.

Yikyū Shionoya (1789–1865) was an eccentric scholar in feudal Japan who developed revolutionary seismic theories 150 years before modern seismology. Combining traditional Japanese earth philosophy with empirical observation, he invented the ‘Dragon-Scale Seismograph,’ using nested bronze bowls and mercury to detect underground vibrations.

Shionoya’s 1831 manuscript Chikyū no Uzu (Whirlpools of the Earth) proposed that earthquakes resulted from subterranean electrical currents—a concept aligning with modern plate tectonics. He established a network of observation posts across Honshu, creating the first earthquake forecasting system. Though ridiculed by contemporaries, his 1847 prediction of the Zenkoji earthquake saved countless lives.

Suppressed during Japan’s Westernization era, Shionoya’s work was rediscovered in 2004. Modern researchers confirm his observations of precursor animal behavior and electromagnetic anomalies before quakes.