ILLUSTRATION CREDITS

Figure 1.1 The DNA molecule, pictured as a spiral staircase (Ray Loadman)
Figure 2.1 Friedrich Miescher (University of Basel/Jakob Höflinger)
Figure 3.1 Nuclei in cells of the milkweed, drawn by Robert Brown (The Linnean Society)
Figure 3.2 Chromosomes during cell division, drawn by Walther Flemming (Zellsubstanz, 1882)
Figure 3.3 Cell division (Ray Loadman)1
Figure 4.1 Gregor Mendel and his brothers at the Abbey of St Thomas in Brünn (Prof. Ondrej Dostál, Gregor Mendel Museum, Brno)
Figure 4.2 Diagram of Mendel’s cross-fertilisation studies (Ray Loadman)
Figure 5.1 Thomas Hunt Morgan in the Fly Room at Columbia University, New York (California Institute of Technology Archives)
Figure 6.1 Albrecht Kossel (University Archives Heidelberg)
Figure 6.2 Purine and pyrimidine bases in DNA and RNA (Ray Loadman)
Figure 7.1 Phoebus Levene (Rockefeller University Archives)
Figure 7.2 A ‘tetranucleotide’ structure for DNA, proposed by Levene (Ray Loadman)
Figure 8.1 X-ray crystallography, apparatus and theoretical basis (Ray Loadman)
Figure 8.2 William Bragg and his son Lawrence (Smithsonian Institution Archives)
Figure 9.1 Mutations in the fruit fly, Drosophila, described by T.H. Morgan’s group (Royal Society)
Figure 9.2 Ribose and deoxyribose, the sugars in RNA and DNA (Ray Loadman)
Figure 10.1 William (Bill) Astbury (Special Collections, Leeds University Library)
Figure 11.1 Fred Griffith (Science Photo Library)
Figure 11.2 Griffith’s experiments on the transformation of pneumococci (Ray Loadman)
Figure 12.1 Oswald Avery (Rockefeller University Archives)
Figure 13.1 The ‘pile of pennies’ structure proposed for DNA by Bill Astbury (Ray Loadman)
Figure 14.1 Nikolai Vavilov, Russian geneticist and botanist (Science Photo Library)
Figure 15.1 John Randall (Royal Society/Godfrey Argent)
Figure 15.2 Maurice Wilkins (Archive Bocher/Lindau Nobel Laureate Meetings)
Figure 17.1 Prisoner No. 7002: Nikolai Vavilov (N. I. Vavilov Research Institute of Plant Industry)
Figure 18.1 Alfred Mirsky and Gulland Masson (Cold Spring Harbor Archives)
Figure 18.2 Erwin Chargaff (Science Photo Library)
Figure 18.3 Chargaff’s Rules (Ray Loadman)
Figure 19.1 Linus Pauling (California Institute of Technology Archives)
Figure 19.2 Molecular structures for DNA proposed by Michael Creeth and Sven Furberg (University of London/Sven Furberg Estate)
Figure 20.1 Ray Gosling’s X-ray photograph of ‘crystalline’ DNA (Nobel Foundation)
Figure 20.2 Francis Crick (Hans Boye/MRC Laboratory of Molecular Biology)
Figure 20.3 Rosalind Franklin (Elliott & Fry/National Portrait Gallery)
Figure 21.1 B299: X-ray photograph of DNA, taken by Elwyn Beighton (Special Collections, Leeds Unversity Library)
Figure 22.1 James D. Watson (Hans Boye/MRC Laboratory of Molecular Biology)
Figure 24.1 The B form of DNA: Photograph 51 and the X-ray diffraction pattern of squid sperm (King’s College Archives and Nobel Foundation)
Figure 24.2 Hydrogen bonding linking adenine with thymine and cytosine with guanine, to bridge the two helical strands of DNA (The Double Helix, 1968)
Figure 24.3 Jim Watson and Francis Crick with their model of the double helix (Science Photo Library)
Figure 24.4 Schematic drawing of the double helix (The Double Helix, 1968)
Figure 25.1 Mechanism of duplication of the two strands of DNA (The Double Helix, 1968)
Figure 25.2 The double helix, refined by Maurice Wilkins (Nobel Foundation)
Figure 25.3 Francis Crick, Jim Watson and Maurice Wilkins with the other Nobel laureates, 1962 (Science Photo Library)
Figure 26.1 Colin MacCleod and Maclyn McCarty at the inauguration of the Avery Memorial Gateway, Rockefeller University (Rockefeller University Archives)