"The process of obtaining images upon sensitized surfaces by the action of light, " has fascinated man for over a hundred years. In 1727, Johann Schulze, a German physician, made a paste of chalk, silver carbonate and possibly silver chloride, which darkened after exposure to sunlight. Limited usefulness was achieved since no method was devised to prevent unexposed areas from eventually tuning dark also, until Louis Daguerre in 1839. He used silver-plated sheets of copper fumed with iodine vapors to form silver iodide. Images were made permanent by dissolving the remaining silver iodide with a solution of common salt. "Daguerreotypes" became the rage. The development of photography as we know it today is largely due to the perfection of flexible film in rolls by George Eastman in 1889. Chemistry, silver iodide and light have had profound effects on the way we live.
