The illustrious French physicist Charles Augustin de Coulomb carried out a series of studies that are at the basis of modern electrostatics. He conducted refined research on magnetism, friction and electricity. He also designed various scientific instruments, including the torsion balance, invented in 1777 and described in a promemorium dating from 1784. Thanks to this instrument, which allowed precise measurement of forces of extremely low intensity, Coulomb conducted various studies on the interaction between electric charges, arriving at the formulation of the law known today by his name. In his honour the unit of measurement of electric charge in the International System has been called the "coulomb" (C). He also published texts in astronomy and mathematics, and may be considered one of the forerunners in applying the principles of mechanics to machines.