These days we have the Pantone Matching System, a widely used colour matching system that's home to just about every colour you can think of, however 271 years before that colour matching system existed an artist simply known by the name of "A. Boogert" wrote a book in Dutch about the use of colour in art and went on to demonstrate how adding different amounts of water can change its tone.
A simple enough idea - at least that's until you see the amount of work and detail that went into creating the book. With nearly 800 pages of handwritten notes and paintings the book, which is titled Traité des couleurs servant à la peinture à l’eau, likely remained the most comprehensive exploration of colour until the Pantone Colour guide came along in 1963.
Medieval book historian Erik Kwakkel, who translated the books introduction says that the book was intended as an educational guide - a shame when you consider that because it was a single copy not many people would have seen it. Nevertheless the book still remains an impressive feat for one artist so many years ago.