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months, Watson and Crick fumbled around with DNA models. All did not go smoothly. One of the difficulties was that Watson and Crick did not have all the materials available to construct a model with the inorganic ions like DNA. With some manipulation of on-hand material they were able to create a model to their liking. Watson and Crick had constructed a beautiful three chain helix representing DNA. The next obvious step would be to check the parameters with Rosy’s quantitative measurements. To their knowledge the model would certainly fit the general locations of the X-ray reflections. Upon completion, Watson and Crick were ecstatic about their accomplishment. To be the first to discover the structure of such an important molecule like DNA was going to make a major impact in the world. A phone call was made to Wilkins asking that he come to Cambridge to view the model and issue his opinion on its validity. The next day both Wilkins and Rosy came to Cambridge to view the model. Watson and Crick had their presentations prepared. They planned to dazzle their audience as they explained how they solved the complexity of the DNA structure. As their discussion went forth, Wilkins was skeptical on many aspects of the model. Rosy was completely dissatisfied with the model, especially with the fact that the model had Mg++ ions holding together the phosphate groups of the three-chain model. She noted that the Mg++ ions would be surrounded by tight shells of water molecules which contradicted the results she had gained on the water content of DNA molecules from her experiments. The rest of the day was spent trying to salvage what little argument Watson and Crick had. Over lunch was no success, neither did they prevail when they returned to the lab. Soon the day was over and Wilkins and Rosy returned to London. When Watson and Crick’s supervisors heard of the failure with the model, they ruled that no further research would be done at Cambridge on DNA. For over a year Watson and Crick let DNA alone, only to be pondered upon while not working on other projects. That year Watson worked on researching the tobacco mosaic virus (TMV). A vital component to TMV was the nucleic acid, so it was the perfect front to mask his continued interest in DNA. Over time and hard work, Watson was able to show that some parts of TMV were helical in shape and thus decided to return to work on the structure of DNA. With more knowledge and expertise the research went forward with passion. Watson had seen an X-ray picture taken by Rosy that to him gave sure evidence that DNA was helical. Wilkins data only furthered his conviction. Watson and Crick were back at it again with a new fervor. They knew that there was a sugar phosphate backbone to the structure and it was held together somehow by the nucleic acids (adenine, thymine, cytosine, and guanine). Watson had a hunch that the shape was going to be a double helix. At first Watson thought the two backbones were held together by a like-with-like structure (adenine-adenine, thymine-thymine, etc.) holding the nucleic acids together with a hydrogen bonds. After about a day Watson realized that a like- with-like structure just was not possible. Watson knew that the amounts of adenine always equaled thymine and amounts of cytosine equaled guanine. With the help of Crick, they tried to construct a model by pairing adenine with thymine and guanine with cytosine. This fell together very nicely. After obtaining several opinions on the validity of their work they placed a call to Wilkins. Wilkins and Rosy came down and to the surprise of Watson and Crick, Wilkins and Rosy were immediately pleased with the model. After comparing results and measuring the model they decided that Wilkins and Rosy would publish a paper at the same time Watson and Crick published their paper, announcing their discovery. This was indeed an incredible discovery for the world, especially for the world of biology. The structure for the “stuff of life” was finally discovered. Watson and Crick went on to win the Nobel Prize for their work. Pauling who had worked so hard to discover the structure was not disgruntled by the fact that someone had beaten him to the discovery, but rather pleased that the problem was finally solved. Everyone was enthusiastic about the new discovery. This was excellent reading. Watson not only told the story of how the structure of DNA was discovered but he also let us in on the developments of parts of his personal life. He would speak of how he tried to have dinners at a school that was teaching young, pretty French girls English. He also spoke much of his relationship with Crick and Crick’s wife, Odile. He made the book come alive and science seem more fun, breaking the stereotype of the scientist. I especially enjoyed how he described Rosy and her firm dedicated feministic attitude. The reader could feel sympathy for the tribulations Wilkins had to go through working with her. The book was an excellent account of the discovery of the structure of DNA. Throughout the text, Watson mostly eluded to the greatness of others rather than to his own greatness. Even though he played probably the most significant part in the discovery of DNA’s structure he gave credit to those that have inspired him.