A vocabulary of landscape — a landscape of words
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Mercalli scale
A seismic intensity scale that measures earthquakes by the effects observed rather than the intensity. The scale runs from I (not felt) through XII (total destruction) and every level is defined by human experience. At IV, dishes rattle and sleepers wake; at VI, furniture moves and plaster cracks. Let’s not talk about IX and up.
Etymology
Named for Italian volcanologist Giuseppe Mercalli, who developed an early version in 1884. The current Modified Mercalli Intensity Scale (MMI) was refined by Harry O. Wood and Frank Neumann in 1931.
Notes
The Mercalli scale and the Richter/moment magnitude scale measure different things. A single earthquake has one magnitude but many intensities, the strongest near the epicenter and weaker with distance.