Whose observations first showed that earthquakes can trigger landslides and surface failure?

Irish engineer Robert Mallet is often called a founder of seismology. In the mid-19th century, he investigated major earthquakes, including the 1857 Great Neapolitan earthquake, and documented the ways shaking causes ground failure, landslides, and destruction. He also helped introduce systematic scientific methods for studying earthquakes. Mallet's work made clear that earthquakes are not just single shocks but events with complex surface effects. His observations influenced both science and the emerging field of earthquake safety.