helix shape, and it was a critical piece of information for Watson and Crick's 1953 model. Rosalind Franklin was the first to acknowleged the two forms of DNA molecule (Type A and B), as well as to hypothesize that the phosphate backbone is outside of the helix. Her work was published third in the series of DNA Nature articles in which she described the structure of Type B DNA molecule, but was overshadowed by Watson and Crick's first publication on the structure of DNA. After leaving King's college, Rosalind Franklin shifted her work to do research and signficant contributions on the tobacco mosaic virus and the polio virus. Franklin died of cancer in 1958 from ovarian cancer.