CHAPTER ONE PHOTOGRAPH 51 It was May 1952 in London England The spring days brought welcome sunshine after the long and dreary English winter But on other days thick clouds of what Britons called London fog descended on the city coating sidewalks streets and buildings with grime This fog was a swirling thick soup of coal smoke factory emissions and toxic chemicals But Rosalind Franklin barely noticed Throughout the spring of 1952 Franklin and her student and laboratory partner Raymond Gosling spent long hours indoors They worked with temperamental cameras and complicated X-ray machines Their damp basement lab at King’s College was in an old house with narrow staircases thin walls and a leaky roof Franklin and Gosling’s experiments could be frustrating Rosalind Franklin hard at work in her lab where she was one of just a handful of female scientists 5
and the math they had to use was complex Yet the work was leading them on a trail of discovery into the fundamental secrets of life Women in Chemistry Women have made important contributions to chemistry since the science began In the late eighteenth century Marie Lavoisier worked as a laboratory assistant to her husband Antoine-Laurent helping him develop a new scientific method for understanding the elements She translated scientific articles from English to French and created beautifully precise drawings of laboratory experiments and equipment Born in Poland Marie Curie worked as a researcher in physics and chemistry in France With her husband Pierre Curie discovered the elements polonium and radium Their studies of radioactivity earned the two a share of the 1903 Nobel Prize in physics After Pierre’s death Marie helped develop the medical use of X rays and won the 1911 Nobel Prize in chemistry making her the first person ever to earn two Nobel Prizes Dorothy Hodgkin like Rosalind Franklin was a skilled X-ray crystallographer Using this method she discovered the structure of penicillin insulin and vitamin B12 She won a Nobel Prize for her work in chemistry in 1964 THE DOUBLE HELIX Franklin and Gosling were creating X-ray images of thin delicate fiber-like structures By measuring the details on the image they could figure out how chemical compounds and molecules invisible even to microscopes made up the structures One image taken by Gosling showed two strands crossing each other in the shape of an X The strands appeared as a series of steps like the rungs of two ladders crossing in the center Franklin and Gosling were not sure what to make of the image but the shape of the strands was clear they 6
showed the structure of a double helix The image was much sharper than many others the scientists had taken in the lab It became known as Photograph 51 Franklin was secretive about her work as were other scientists working in the lab They wanted the opportunity to announce discoveries as their own Instead of showing the image to her colleagues she kept it with other images in her office When she was ready with her calculations and findings she would write everything in a paper She would share the paper with a few other scientists at King’s College Then she would announce her findings at a lecture or seminar She would seek input from her scientific peers and then prepare an article for publication in a journal This would allow her to claim a discovery if in fact the photograph showed anything significant Gosling and Franklin were also competing with other scientists in England and in the United States In fact James Watson and Francis Crick members of the prestigious Cavendish Laboratory at Cambridge University were working on the same problem the structure of deoxyribonucleic acid or DNA for short the molecule that passes genetic information from parents to offspring Linus Pauling a molecular chemist at the California Institute of Technology was publishing articles on this very subject and he was drawing near to a solution 7