20th century in science biologically relevant molecules, they were, till the end of the 20th century, more a collection of rules, observations, and recipes than rigorous ab initio quantitative methods. This heuristic approach triumphed in 1953 when James Watson and Francis Crick deduced the double helical structure of DNA by constructing models constrained by and informed by the knowledge of the chemistry of the constituent parts and the X-ray diffraction patterns obtained by Rosalind Franklin. This discovery lead to an explosion of research into the biochemistry of life. In the same year, the Miller–Urey experiment demonstrated that basic constituents of protein, simple amino acids,
Maurice Wilkins deduced from her X-ray diffraction data. Watson and Crick published their proposed DNA double helical structure in a paper in the journal "Nature" in April 1953. In this paper Watson and Crick acknowledged that they had been "stimulated by... the unpublished results and ideas" of Wilkins and Franklin. The first Watson-Crick paper appeared in "Nature" on 25 April 1953. The members of the Cambridge and King's College laboratories agreed to report their interlocking work in three papers with continuous pagination in "Nature". Sir Lawrence Bragg, the director of the Cavendish Laboratory, where Watson and Crick worked, gave a talk at