Today's interesting fact has to do with modern photography.

When I went to school, Louis Danguerre was said to have been the father of modern photograpy.

However, a Joseph Niepce, a number of years before had developed created a process that, using bitumen and lavender oil on metal plates, created an image that could be used to produce prints. Unfortunately it took between 8 and 42 hours to produce an image.

Niepce died of a stroke in 1933 and left his notes to Danguerre who then worked out how to use silver, iodine vaper and mercury fumes to create a latent image.

Of course, pin hole camers have been around for a long time, the Greeks and Chinese had both invented them in the 4th and 5th centruies BC. Camera obscuras were used in the 6th century CE, in eastern Europe, and early Muslim scolars studied cameras as well.