Jean-Charles, chevalier de Borda (4 May 1733 – 19 February 1799) was a French mathematician, physicist, and Navy officer.

[1][2] In 1756, Borda wrote Mémoire sur le mouvement des projectiles, a product of his work as a military engineer.

In 1778, he published his method of reducing lunar distance for computing the longitude, still regarded as the best of several similar mathematical procedures for navigation and position fixing in pre-chronometer days.

Another of his contributions is his construction of the standard metre, basis of the metric system to correspond to the arc measurement of Delambre and Méchain.

[3] This required the calculation of trigonometric tables and logarithms corresponding to the new unit and instruments for measuring angles in the new system.