This page concerns the discovery of the DNA molecule and the discovery of its structure.
The DNA molecule was discovered by Friedrich Miescher in 1869. He accomplished this by mixing alcohol and pig's stomach juice over bandages containing pus (these were given to Miescher from the local hospital). However, people paid little attention to the molecule until 1952, when its biological role was discovered. In this year, Linus Pauling attempted to determine the structure of the DNA molecule, but was unable to find a structure that could exist. The next year, in 1953, the scientists James Watson and Francis Crick discovered a plausible double-helix configuration using X-ray crystallography.
Sam Kean (2011) The Disappearing Spoon