Maurice Wilkins by James Watson. During the second phase, 1951–52, Wilkins produced clear "B form" "X" shaped images from squid sperm, images he sent to James Watson and Francis Crick, causing Watson to write "Wilkins... has obtained extremely excellent X-ray diffraction photographs" [of DNA]. In 1953 Wilkins' colleague Rosalind Franklin instructed Raymond Gosling to hand over to Wilkins a high quality image of "B" form DNA ("Photo 51"), which she had made in 1952 but had “put it aside” as she was leaving King's College London. Wilkins showed it to Watson. This image, along with the knowledge that Linus Pauling had proposed
Timeline of United States discoveries chloride 1936 Elliptical galaxies 1936 Muons 1936 Vitamin E 1936 Sodium thiopental 1937 Niacin 1937 Electron capture 1938 Fluropolymers 1938 Animal echolocation 1938 Carme 1938 Lysithea 1940 Plutonium 1942 Cyanoacrylate 1943 Streptomycin 1944 Americium 1944 Curium 1946 Cloud seeding 1948 Warfarin 1948 Miranda 1948 Serotonin 1948 Tetracycline 1949 Nereid 1949 Berkelium 1950 Californium 1951 Barium stars 1951 Ananke 1952 Polio vaccine 1952 Einsteinium 1952 Rapid eye movement 1953 DNA structure In 1953, based on X-ray diffraction images and the information that the bases were paired, James D. Watson along with Francis Crick co-discovered what is now widely accepted as the