Italy has been pioneering the instrumental measurement of earth motions, and among them the measurement of tremors.

Around 1870 Timoteo Bertelli designed and built in Bologna an accurate yet simple, light and comparatively inexpensive instrument to measure the tremors of the earth. He named it tromometer from the name of the ancient Greek word for tremors, τρομος.

The original tromometer consisted essentially of a horizontal pendulum made by a mass of 100 g suspended by a very thin copper wire 150 cm long and encased in a tube to protect it from air currents. The position of the mass was observed through a microscope with a micrometric eyepiece, which could easily resolve tremors with amplitude < 10^-6 m.