October 31, 1794 - John Dalton presented his study on the disease that is now associated with his name, Daltonism

In 1794, Dalton was elected to the Manchester Literary and Philosophical Society, better known as "Lit&Phil", where he presented his first paper, "Extraordinary Facts Concerning Color Vision", which posited that deficiencies in color perception are due to abnormalities of the vitreous humor. It was the first time that not only the fact of the lack of color perception in some people was described, but also an explanation for the phenomenon was given. Although his theory was discredited while he himself was alive, his thorough and methodical investigation of his own visual problem made such an impression that his name became the common term for color blindness, color blindness.

Dalton discovered that he saw colors differently while conducting botanical research and left instructions that his eyes be preserved, allowing DNA analysis, published in 1995, to show that he actually suffered from a less common type of color blindness. , deuteranopia. He was only able to see blue, purple and yellow.

This blindness to certain colors sometimes hindered his scientific work, especially in the laboratory where he mixed up reagent bottles, or in social aspects, such as when he went to meet King William IV in 1832. He wore scarlet academic dress, an unusual color for a man like him and that surprised his acquaintances. The reason was that Dalton saw her as dark gray.

If you want to know more about this scientist and his many achievements, click on the following link: John Dalton