Includes bibliographical references (pages 445-496) and index.

The path to the discovery of the molecular structure of DNA was one of the most dramatic in the history of science. This volume is the complete story of that landmark event. The roots of the story of the genetic "secret of life" are in nineteenth-century molecular biology; in 1869, a substance which corresponded to DNA, "nuclein," was discovered. For nearly a hundred years, however, the structure of the molecule proved more elusive than scientists had thought. In this book, the author develops five major themes: long-chain macromolecules; nucleoproteins; bacterial transformations; the intellectual evolution of structural chemists and physicists, including Crick and Watson, into biologists; and the way in which combined scientific approaches led to the conclusions about the molecular structure of DNA.-- Section I. From colloidal particles to long-chain molecules: Bergmann, Staudinger, Svedberg, Polanyi, Mark, Astbury -- 1. The macromolecule -- 2. The ultracentrifuge -- 3. The fibre diagram and the long-chain molecule -- 4. The Leeds school under Astbury -- 5. Astbury under attack -- Section II. Nucleic acids and the nature of the hereditary material: Kossel, Levene, Garrod, Caspersson, Beadle, Muller, Darlington, Stanley -- 6. Kossel, Levene and the tetranucleotide hypothesis -- 7. The nucleoprotein theory of the gene -- 8. The physiology of the gene -- 9. The enzyme theory of life -- 10. The chemistry of virus-genes -- Section III. Bacterial transformation, its nature and implications: Griffith, Avery, Boivin, Vendrely, Chargaff, Wyatt -- 11. Bacterial transformation -- 12. The identity of the transforming substance -- 13. Support for Avery -- 14. Base ratios -- Section IV. Intellectual migrations: Delbrèuck, Schrèodinger, Bernal, Perutz, Pauling, Watson and Crick -- 15. Physicists in biology: the informational school -- 16. Physicists and chemists in biology: the structural school -- 17. Pauling, Caltech and the [alpha]-helix -- 18. Watson and Crick -- Section V. The hunt for the helix: Furberg, Wilkins, Gosling, Franklin, Watson and Crick -- 19. DNA as a single or multiple-helix -- 20. DNA as a triple helix -- 21. DNA as a double helix -- 22. Conclusion.