Britney Gallivan Britney Gallivan Britney Crystal Gallivan (born 1985) of Pomona, California, is best known for determining the maximum number of times that paper or other materials can be folded in half. In January 2002, while a junior in high school, Gallivan demonstrated that a single piece of toilet paper 4000 ft (1200 m) in length can be folded in half twelve times. This was contrary to the popular conception that the maximum number of times any piece of paper could be folded in half was seven. She calculated that, instead of folding in half every other direction, the least volume of
Paper texture effects in calotype photography make them more transparent. Since many prints could be made from a single negative, travel photography became possible, and prints from calotypes were soon distributed in book form and sold in shops. The chemical operations used to make a calotype were not difficult to perform, and relatively few specialized supplies were required. But the process had a serious deficiency, and it was quickly replaced by photography on glass when this became practical. Paper texture limits what can be done with the calotype process. This texture can be seen by holding a piece of copier paper up to the light: the