Seismologist Michele Stefano de Rossi and limnologist François-Alphonse Forel had each created their own intensity scales and in 1883 came together to join their efforts and formulate the 10-level Rossi – Forel scale . In 1902 , Giuseppe Mercalli updated the scale to include descriptions of how individuals responded to the earthquake , and Adolfo Cancani later proposed extending the scale to 12 levels . The German physicist August Heinrich Sieberg executed the change and called it the Mercalli-Cancani-Sieberg ( MCS ) scale which became popular in Europe . Wood and seismologist Frank Neumann devised their own 12-level scale in 1931 , removed Cancini and Sieberg 's names , and called it the Modified Mercalli Intensity Scale . One of the first uses for the new scale was in a report Wood furnished to the Seismological Society of America regarding the effects of the 1933 Long Beach earthquake where its intensity was placed at VIII ( '' Severe '' )
1933 Long Beach earthquake
1933 Long Beach earthquake
Harry O. Wood