The kings great triumphs were the conclusion of the Intercursus Magnus of 1496 and the Intercursus Malus (so called by the Flemings, not by the English) of 1506.
The fact that other philosophers, notably Etienne Louis Malus and Augustin Fresnel, were pursuing the same investigations contemporaneously in France does not invalidate Brewster's claim to independent discovery, even though in one or two cases the priority must be assigned to others.
The phenomenon of polarization observed by Huygens remained an isolated fact for over a century, until Malus in 1808 discovered that polarization can be produced independently of double refraction, and must consequently be something closely connected with the nature of light itself.
ETIENNE LOUIS MALUS (1775-1812), French physicist, was born at Paris on the 23rd of June 1775.
The Malus Intercursus on the other hand gave England some privileges which she had not before enjoyedexemption from local tolls in Antwerp and Holland, and a licence for English merchants to sell cloth retail as well as wholesalea concession which hit the Netherland small traders and middlemen very hard.
T Malus gave the name of polarization, as he attributed it, on the emission theory of light, to a kind of polarity of the light-corpuscles.