Caspar Wessel, a surveyor born in 1745, presented his only math paper "Om Directionesns Directionens analytiske BetgningBetegning" (in Danish) in 1797 at the age of fifty two on complex numbers. His paper was forgotten for almost 100 years until his paper was translated into french in 1878(?). In the meantime Gauss in 1831 and Argand in 1806 re discovered Wessel's idea.
By reading the texts in Complex Numbers you will hardly know the contributions Wessel.

