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
Scientific Revolution principles—of spirits operating in nature. Practical attempts to improve the refining of ores and their extraction to smelt metals were an important source of information for early chemists in the 16th century, among them Georg Agricola (1494–1555), who published his great work "De re metallica" in 1556. His work describes the highly developed and complex processes of mining metal ores, metal extraction and metallurgy of the time. His approach removed the mysticism associated with the subject, creating the practical base upon which others could build. English chemist Robert Boyle (1627–1691) is considered to have refined the modern scientific method for