Guiseppe Mercalli (1850-1914) was an important Italian seismologist. Born in Milan, he was a teacher at various private schools there before being elected professor in the Liceo Campanella of Reggio Calabria, and moving through various other professorships before becoming director of the Vesuvian observatory in 1911. His professional life was therefore spent close to the seismic and volcanic districts of Italy. As well as his two important memoirs on the subject, he also investigated several important individual earthquakes, from the one in Ischia in 1883, to those in Calabria in 1894, 1905 and 1907, to the Messina earthquake of 1908. He developed his own scale of intensity for earthquakes, and his writings were of great importance to seismological studies of the time. He died, perhaps prematurely, due to the spilling of a petroleum lamp.