The Italian scientist and inventor Tito Filippo Gonnella (1794–1867) is primarily known as the inventor (in 1824) of one of the first planimeters in the world.
These two machines worked as mechanical calculator devices. They assisted in addition calculations and helped lead to more complex calculation machines.
As a professor of mathematics and mechanics, Gonnella is believed to have created these machines as a way to advance the field and improve the adding machine technology.