Rosalind Franklin (17 page)

Pauling's paper, written with his colleague Robert Corey, had been published only two months before the Stockholm meeting in the April and May issues of
Proceedings of the National Academy of Sciences.
At Stockholm he was describing his discovery to an international audience for the first time.

Another speaker at the Stockholm conference was the acclaimed J.D. Bernal from Birkbeck. One of the first to turn X-ray diffraction methods onto giant molecules such as proteins, he addressed, with obvious reference to Pauling, the alternative approaches to working out molecular structures: speculative, deductive and inductive. Whichever was followed — and he did not suggest which was best — the resulting proposal had to be put to the test of X-ray analysis. The important thing, declared Bernal, was to review the evidence and the assumptions, then to ask oneself: ‘Have we found
the
solution? Or
a
solution?'

Rosalind took this commandment to heart. She wrote it down with strong underlinings:
‘the
solution or
a
solution'. She did not manage to meet Pauling personally.

A less formal conference was held in July at Bragg's Cavendish Laboratory in Cambridge. Max Perutz called, as he had the year before, a meeting of those working on X-ray analysis of protein structure. The Cavendish had a research unit, similar to that at King's and financed by the same source, the Medical Research Council. It was smaller than Randall's outfit and was studying protein by X-ray diffraction. Perutz, a brilliant and witty Austrian transplanted to Cambridge in 1936, was trying to solve the dauntingly intricate structure of haemoglobin, the major protein in red blood cells. His colleague John Kendrew was trying to do the same with the smaller protein, myoglobin (‘myo' means muscle).

By the mid-summer of 1951 the atmosphere in Britain had brightened considerably. The Festival of Britain opened, designed to lift the country out of the doldrums: ‘the people giving themselves a pat on the back', said the Labour politician Herbert Morrison. Set up on London's South Bank, the exhibition was a £12 million, five-month expression of nationalist faith in the British imagination to conquer new worlds — in art, in architecture and, not least, in science. J.T. Randall and Sven Furberg were not alone in believing that Britain's victory against terrible odds sprang from its scientific genius.

At Perutz's conference, Wilkins spoke, as he had at a similar meeting the previous year, about the DNA work at King's. All the different X-ray patterns that they were getting, he said, showed a clear central x. Alec Stokes had informed him that this was a strong sign of a helix. It seemed, Wilkins concluded, that all DNA had the same unique, twisting structure. He was applauded.

But not by everyone. Rosalind was waiting for him as he left the hall. She told him, in firm and deliberate tones, to return to his optical studies — in essence, to give up X-ray work. Her actual words as he remembered them, were ‘Go back to your microscopes.'

Wilkins was profoundly shaken. No one in science had ever talked to him like that. And why was she ordering him, the assistant director of the lab, to stop work just as he reported encouraging progress? He wondered if the success of his talk had disturbed her.

The rift was Randall's doing. Rosalind assumed that Stokes and Wilkins were moving off DNA, whereas Wilkins, never having seen Randall's letter to her containing the poisonous phrase — ‘as far as the experimental X-ray effort is concerned there will be at the moment only yourself and Gosling' — expected that he, with Stokes, would analyse the photographs that Rosalind and Gosling took.

(Decades later Wilkins reasoned that Randall deliberately manipulated the misunderstanding, in order to push him aside and himself get back into what was revealing itself as the most exciting project in biophysics.) For all his building of a big department, Randall had no piece of the action himself. Others have speculated that Randall wanted to get into the work because he was disappointed with the slow progress King's had been making under Wilkins.

News of the row swiftly spread to others on the King's team who had come up to Cambridge. When they went punting on the Cam, Geoffrey and Angela Brown were with Maurice in one boat, Rosalind with friends in another. Maurice looked up and saw Rosalind with the punt pole bearing down on them in what he saw as a menacing way. ‘Now she's trying to drown me!' he said. They all laughed, but it wasn't funny.

Rosalind was not one to do without a proper holiday. Hearing that Margaret Nance, her Unesco friend from Paris, now in London, was organising a party to go in August to the Ile de Batz off the coast of Brittany, she asked if she might join. Arriving after the others, Rosalind found that there was no accommodation for herself and another late arrival, Norma Sutherland. After spending one night sleeping on the floor of a barn, the two women decided to return to the mainland to seek accommodation. There appeared to be none, but Rosalind, with her determination and excellent French, found rooms. The holiday went well; a photograph taken at Quimper shows Rosalind, with a fullskirted floral print twinned with a tailored anorak, the most stylish of the trio. Norma, seeing her at close range, then, and over the next few months, got a clear view of a double-sided personality:

Her manner was brusque and at times confrontational — she aroused quite a lot of hostility among the people she talked to, and she seemed quite insensitive to this. But she was kindness itself to me and I have fond memories of that week together. I think she needed friends away from her workplace. A couple of months later I was to leave for home [Australia] and she invited me to lunch to say goodbye and presented me with a little gift to occupy the long hours on the voyage. I was touched by this gesture which showed a much softer side of the Franklin character.

After Brittany Rosalind put her bicycle onto the train and on 16 August, after travelling all night, arrived in the Dordogne and bicycled to the village of St Leon sur Vezère, where her old St Paul's friend Anne Crawford, now Piper, and her husband Michael had rented a derelict farmhouse. She came even though warned that one Piper child had chickenpox. Anne knew that Rosalind was always good with her brood — relaxed, generous, imaginative — and they spent a good week playing with the children and visiting the caves at Lascaux. As with children, so with landscape; in both Rosalind found release from the tensions of life and laboratory. To Adrienne she wrote from the Dordogne of ‘a heavenly view across the valley and no human beings within miles'.

News of the confusion about who was doing what at King's College London reached Caltech in Pasadena. So too had word of some excellent X-ray photographs of DNA. Linus Pauling had in the back of his mind that having solved one part of the cell's mysteries, the protein, he might as well get the nucleic acid as well. Brazenly he wrote and asked Randall to send to him the DNA X-ray photographs of DNA, as he understood from a friend of Wilkins that Wilkins was not planning to interpret them.

Randall gave the great man a dusty answer. ‘Wilkins and others,' he replied, were ‘busily engaged' in working out the interpretation of the desoxyribose nucleic acid X-ray photographs and it was natural that Wilkins should wish to carry on. He added, with an ethical flourish, ‘It would not be fair to them, or to the efforts of the laboratory as a whole, to hand these over to you.' In any case, he told Pauling, as Wilkins was to speak about his work at a conference in the United States, there should be no mystery about what King's was accomplishing.

Before Wilkins left for the States and while Rosalind was away, he asked his colleague Stokes if he could work out what sort of an X-ray pattern a helical structure would give. Indeed Stokes could. It took him twenty-four hours, the crucial calculations being done on his commuter train home to Welwyn Garden City. They were correct. Stokes, like Avery, an unusually quiet and reserved man, allowed later that he sometimes thought his result ‘worth perhaps 1/5000 of a Nobel prize'.

Wilkins put the information in a letter to Crick, saying that he and Stokes now felt that the DNA molecule had the shape of a helix. To make his point, he sketched a diagram of a helix in the margin. Crick's reply was that Wilkins was wasting his time; the protein molecule, not DNA, was the thing to study.

Not to Stokes. His mathematical diagram of undulating lines made such a pretty picture that he named it ‘Waves at Bessel-on-Sea'. (Bessel functions are mathematical devices used in structure calculations; Bexhill-on-Sea is a seaside town in Sussex.) Wilkins pinned it up on the laboratory bulletin board and left for his Gordon Conference (part of an annual series of summer conferences on scientific topics, held at a school in the White Mountains of New Hampshire). He also left Rosalind a note.

Stokes has supplied a few good things on helices & I have done more swelling & shrinking of fibres. The cross section increases by a factor between 3.7 & 4 on swelling to 100% humidity, Length 40—30%.

I think these simple
volume
experiments probably good enough to tell the no. chains p.u. cell [number of chains per unit cell].

Wilkins ventured some suggestions about the density and the pitch of the chain, or chains, and concluded cheerily, ‘Hope you have a good holiday, MW.'

The note was waiting when Rosalind got back from France. She had had a splendid holiday; now it was spoiled. She did not find Stokes's wave patterns pretty, but rather an intrusion on her assigned territory.

She had been getting remarkable results. The only researcher working at high humidity, determined to get the best possible photographs before embarking on interpretation, she took sharp clear pictures that revealed something no one had noticed before. There were two forms of DNA. When hydrated, the fibre became longer and thinner. When placed over a drying agent, it changed back. This transformation explained why Astbury's patterns had been difficult to interpret further. All earlier attempts to understand DNA's structure had been looking at a blur of the two forms. Rosalind and Gosling were tremendously excited by this finding.

They called the new, longer, thinner, heavily hydrated DNA, ‘wet', or ‘paracrystalline' or, more simply, the ‘B' form. The other, shorter, drier alternative, which they could reproduce at will, was ‘dry', ‘crystalline' or the ‘A' form.

This achievement was essential to the great discovery that lay in wait. Rosalind's skill in chemical preparation and X-ray analysis that Bernal later called ‘among the most beautiful X-ray photographs of any substance ever taken' had given the first clear picture of DNA in the form in which the molecule opens up to replicate itself.

When Wilkins returned from the United States, he saw Rosalind's new sharp B pattern and was impressed by its corroboration of Stokes's Bessel calculations. He called this to her attention. Might other kinds of DNA give a B picture as well? He now had some DNA samples of his own, given to him by Erwin Chargaff at Columbia. Perhaps the three of them - Franklin, Wilkins and Stokes - should collaborate?

 

DNA ‘A' and ‘B' forms

 

Collaborate? She exploded. It was the only time that Wilkins saw her completely lose control. ‘How dare you interpret my data for me!' Rosalind had good reason. Her work was her life, the core of her identity. Undervalued at King's, she had just achieved extraordinary results by working in virtual isolation. Now what she saw as a less able colleague of higher rank was proposing to elbow in and spoil the clarity of her investigation.

Where Wilkins saw rage, one of her brothers saw despair. One night when Colin Franklin and his wife Charlotte were expecting Rosalind to dinner at their home in Hampstead, he was startled to see her arrive in tears — ‘weeping' as he recalled, ‘beyond redemption'. In the Franklin manner, he pretended not to notice and said nothing.

By late October Rosalind was so miserable that she was ready to abandon her work. She poured her heart out to her old friend and confidante, Adrienne Weill.

Dear Adrienne,
I'm sorry I have been silent so long. I came back from my holiday to the blackest of crises in the lab, which lasted weeks and weeks, took all my energy and left me too fed up to write to anybody. Things have calmed down a little now, but I still want to get out as soon as possible, and think seriously of coming back to Paris if Paris will have me.

On 25 October 1951, with ‘one more heave', the Conservatives ousted Labour in the general election and were back in power, with Winston Churchill prime minister once again. At almost the same time, Randall was forced to recognise the contest within his own borders. He called Wilkins and Rosalind to his office, for a meeting from which a treaty of sorts emerged. Rosalind, using the Signer DNA, would concentrate on the A form. Wilkins would tackle the B. From then on communications between the two virtually ceased.

Far from settling the matter, the formal division of labour made things worse, for as Rosalind took all the Signer DNA with her, plus the Phillips micro-camera, Wilkins was left with the pig thymus DNA supplied by Chargaff, and older equipment. Worse luck, the Chargaff DNA did not crystallise, presumably because of its low molecular weight, and Wilkins was thus unable to duplicate the A-B transition.