Ferdinando Visconti (Palermo, 3 January 1772 – Naples, 26 September 1847)
Visconti, son of a colonel in the Neapolitan army, was a cadet since the age of 3 at the Real Napoli regiment. In November 1786 he entered the Military Academy of Naples, which he left on 27 February 1791 as a second lieutenant of artillery and engineers, then was employed at the same school as a mathematical teacher. His scientific interests included geography, astronomy and nautical science, and he published a work on the piloting and manoeuvring of ships.
He was part of the “Jacobin” group who contacted the squadron of the French admiral Latouche-Tréville in 1793. On 3 October 1794 he was condemned to 10 years of prison for conspiracy. He was freed in 1801 following the terms of the treaty of Florence between France and the Kingdom of Naples. He was proposed as a successor to Giovanni Antonio Rizzi Zannoni as director of the topographical establishment, but King Ferdinand IV vetoed his nomination. He then moved to Milan, where he was made a lieutenant 2nd-class of the topographer corps on 7 September 1802. Despite being acting deputy director of the War Depot from 1804, only on 21 September 1809 was he named captain 2nd-class; then on 23 August 1810 he was promoted to captain 1st-class and on 8 July 1813 squadron chief deputy director. In 1808 he started working on a map of the Adriatic Sea.
He went back to the Kingdom of Naples, when Murat was still King, with the fall of the Kingdom of Italy in the spring of 1814. He was there tasked with founding and directing a General War Depot. In January 1817 he was appointed director of the Topographical Bureau, which was separated from the Depot. From 1817 to 1820 he managed to accomplish several key geodetical and topographical operations for the cartography of the Kingdom. He also experimented with lithographic printing, which culminated in the Military Lithography in 1823.
During the 1820 uprisings, he was appointed a member of Parliament and took an active part in the reforms of the army. For this reason, he was forced to quit the army and the direction of the Topographical Bureau at the return of King Ferdinand I (the same king as had condemned him in 1794) in 1821. Between 1822 and 1830 he still planned and executed geodetical operations as a member of the Neapolitan Academy of Sciences. On 8 July 1828 he there presented a memoir on the measurement system (Del sistema metrico uniforme che meglio si conviene a dominj al di qua del faro del regno delle Due Sicilie letta il dì 8 luglio 1828) where he defended the traditional Neapolitan system, though introducing the decimal system.