Contrary to the somewhat tentative spirit of the scientific paper, in his personal communications about the proposed model, Pauling expressed more confidence and was extremely upbeat. In a letter to the Scottish biochemist (and eventual Nobel laureate) Alexander Todd, dated December 19, 1952, Pauling wrote: “We have, we believe, discovered the structure of the nucleic acids. I think that it will be about a month before we send off a manuscript describing the structure, but I have practically no doubt about the correctness of the structure that we have discovered . . . The structure is really a beautiful one.” In a letter sent on the same day to Henry Allen Moe, president of the Guggenheim Foundation, Pauling repeated the same sentiment: “I have now discovered, I believe, the structure of the nucleic acids themselves.”

Another person with whom Pauling was corresponding regularly was his son Peter, who, as luck would have it, had arrived at Cambridge just a few months earlier to work as a research student with John Kendrew. Peter’s desk was in an office with four other colleagues. In Peter’s words: “To my left, near the window, was a rather noisy fellow named Francis Crick. On my right was a desk occasionally occupied by Jim Watson. Also in the room was a visiting scientist, Jerry Donohue, whom I knew well from his long association with Caltech, and Michael Bluhm, John Kendrew’s research assistant.” In a pre-email era, Peter, through his frequent exchange of letters with his father, became the main line of communication between Caltech and Cambridge. Consequently, as soon as Linus informed Peter of his paper on the structure of DNA, the latter asked for a copy. This was on January 13, 1953. Peter added in his letter a brief comment that spoke volumes about the pressure the British scientists were feeling: “I was told a story today. You know how children are threatened ‘You had better be good or the bad ogre will come get you.’ Well, for more than a year, Francis [Crick] and others have been saying to the nucleic acid people at King’s ‘You had better work hard or Pauling will get interested in nucleic acids.’ ”

Under these conditions, it was only natural that the news from Peter that Pauling had discovered the structure of DNA hit Watson and Crick like a thunderbolt. With the memory of Pauling’s previous victory with the alpha-helix still fresh in the minds of everybody at Cambridge, the two young men were wondering if this was a catastrophic case of déjà vu. On January 23 Peter sent Linus another letter, this time complaining only that “I wish Jim Watson were here [Watson was on a quick visit to Milan, Italy]. It is rather dull now. Nothing to do. No interesting girls, just young affected little things only interested in sex, in an indirect manner.”

The weeks between Peter’s request for a copy of Pauling’s paper, and the manuscript’s arrival on January 28, felt like an eternity to Watson and Crick. When Peter finally brought the paper, Watson quickly pulled it out of Peter’s outside coat pocket, and instantly devoured the summary and the introduction. Then, after staring at the illustrations for a few minutes, he couldn’t believe his eyes. Pauling’s structure, with the phosphates in the center and the bases on the outside, was strikingly similar to his and Crick’s abortive model. The model was preposterously wrong!