Color blindness all variations in human color vision involve the red and green receptors in male eyes. It is very rare for males or females to be "blind" to the blue end of the spectrum. The first scientific paper on the subject of color blindness, "Extraordinary facts relating to the vision of colours", was published by the English chemist John Dalton in 1798 after the realization of his own color blindness. Because of Dalton's work, the general condition has been called "daltonism", although in English this term is now used only for deuteranopia. Color codes present particular problems for those with color
Henri Moissan "grade universitaire" necessary to attend university. He began working for a chemist in Paris, where he was able to save a person poisoned with arsenic. He decided to study chemistry and began first at the laboratory of Edmond Frémy and later at that of Pierre Paul Dehérain. Dehérain persuaded him to pursue an academic career. He passed the baccalauréat, which was necessary to study at university, in 1874 after an earlier failed attempt. During his time in Paris he became a friend of the chemist Alexandre Léon Étard and the botanist Vasque. He published his first scientific paper, about carbon