Italy 1850-1814 Giuseppe Mercalli was an Italian volcanologist, seismologist, and Roman Catholic Priest.(1) He is best known for developing an earthquake intensity scale. (1) Born and educated in Milan, he became a professor at a local seminary after graduating college. (1) Mercalli was soon removed from the seminary, but the Italian government quickly found him new positions in schools across the country.(1)
In 1892, he had relocated to Naples, where he would spend the rest of his life by the volcano he studied most closely, Vesuvius.(1) He died a mysterious death in 1914, burning in a fire in his apartment. At first, it was deemed an accident, but within days speculation arose that he was murdered. (1)
His most famous achievement to solid earth science is his work on the earthquake intensity scale. While studying seismic activity in Italy in the late 19th century, his access to seismic instruments was limited. (1) Some seismographs and seismoscopes (devices that signal an earthquake has occured, and sometimes indicate direction) were available, but most of his information came from personal observation of damage and listening to accounts. (1) To provide some consistency to his earthquake analyses, he decided he need a method to rate the relative effects of each event.
(1) At first, his scale had six degrees, but he soon realized he needed more precision. (1) ARound the same time, another intensity scale, the deRossi-Forel scale was gaining in prominence. (1) It had ten degrees of intensity, but lacked detail in the description of each degree. In 1902 Mercalli modified this scale to include the detail he desired, and his new scale quickly caught on among Europe’s scientists. (1 )It was tweaked by other seismologists to twelve degrees and also had more refined descriptions. (1) This edited version was called the Modified Mercalli intensity Scale. (1)
The Mercalli intensity scale is from 1 to 12. This link will provide more information and a comparison between the Richter and Modified Mercalli scales: http://www.geo.mtu.edu/UPSeis/Mercalli.html
Part 2 Earthquakes Intensity: Modified Mercalli Scale http://www.appstate.edu/~abbottrn/mercalli/intnsty.htm