We photograph history. Histogram brings the things people made and found into focus: the inventions, discoveries, maps, buildings and books that changed what people could do. How did a librarian measure the size of the Earth with the shadow of a stick? How did an Ottoman admiral draw the coast of a continent he had never seen? What had to be invented before a single page could be printed? Each film takes one thing and one question: what the problem was, who solved it, how it works, and what changed afterward. Built from the sources that survive. New documentaries every Thursday and Sunday.