Doctor J. Schulze mixed chalk, nitric acid, and silver precious metal in a flask one day and noticed darkening on the area of the flask after contact with light. This was the unintentional creation of the first photosensitive element. He pointed out that the side of the flask subjected to sunlight had a darker color than the ones that were not exposed.
Johann Heinrich Schulze was a German teacher and mathematician from Colbitz in the Duchy of Magdeburg. Schulze pursued medicine, chemistry, idea and theology and became a teacher in Altdorf and Halle for anatomy and many other subjects.