The Italian government appointed him a professor at Domodossola, followed by a job at Reggio di Calabria.

Giuseppe Mercalli also observed eruptions of the volcanoes Stromboli and Vulcano in the Aeolian Islands.

In 1914, Mercalli burnt to death under suspicious circumstances, allegedly after knocking over a paraffin lamp in his bedroom.

His body was found, carbonized, by his bed, holding a blanket which he apparently attempted to use to fend off the flames.

The scale currently in use assigns indices ranging from I ("Not felt, except by a few under favorable conditions"), to XII ("Damage total; objects thrown into the air").