"At once I felt something was not right. I could not pinpoint the mistake, however, until I looked at the illustrations for several minutes. Then I realized that the phosphate groups in Linus' model were not ionized, but that each group contained a bound hydrogen atom and so had no net charge. Pauling's nucleic acid in a sense was not an acid at all...a giant had forgotten elementary college chemistry."

James Watson. The Double Helix.

"I believe that the same process of moulding of plastic materials into a configuration complementary to that of another molecule, which serves as a template, is responsible for all biological specificity. I believe that the genes serve as the templates on which are moulded the enzymes that are responsible for the chemical characters of the organisms, and that they also serve as templates for the production of replicas of themselves. The detailed mechanism by means of which a gene or a virus molecule produces replicas of itself is not yet known. In general the use of a gene or virus as a template would lead to the formation of a molecule not with identical structure but with complementary structure. It might happen, of course, that a molecule could be at the same time identical with and complementary to the template on which it is moulded."

Linus Pauling. "Molecular Architecture and the Processes of Life." May 28, 1948.

"I may say that I would not want to condense these papers into a single paper, because the subjects are different, although, of course, closely related....You can now see that these papers really differ from one another, and that the amount of new material is such that it would be wrong to confuse the reader by lumping everything into a single paper. We may later - without doubt we shall - write some very detailed accounts of the whole business. I feel that this is the greatest step that has ever been taken toward the solution of the general protein problem."

Linus Pauling. Letter from Linus Pauling to E. Bright Wilson. March 7, 1951.

"I hope you'll write to Prof. J. T. Randall, Kings College, Strand, London. His coworker, Dr. M. Wilkins, told me he had some good fibre pictures of nucleic acid."

Gerald Oster. Letter to Linus Pauling. August 9, 1951.

"The proposer of this extraordinary formula for the nucleic acids has not quoted any significant evidence in support of it. The ligation of five oxygen atoms about each phosphorous atom is such an unlikely structural feature that the proposed phospho-tri-anhydride formula for the nucleic acids deserves no serious consideration."

Linus Pauling Verner Schomaker. J. Am. Chem. Soc. 74: 1111. 1952.

"Perhaps you will be interested, in a few years, to consider the possibility of spending your sabbatical year in Pasadena. I hope that our work will be in just as interesting a period after a few years as it is now. In particular, the problem of the structure of the nucleic acids may just be developing into a stage of rapid progress; right now not very much is being done, from the x-ray standpoint."

Linus Pauling. Letter from Linus Pauling to Charles M. Apt. April 9, 1952.

"During recent years my work on the theory of resonance in chemistry has been under attack in Russia. Russian chemists have been forbidden to make use of this theory in their scientific work. The action of the State Department in refusing me a passport represents a different way of interfering with the progress of science and restricting the freedom of the individual citizen."

Linus Pauling. "Statement by Linus Pauling." April 22, 1952.

"The only reason that I am pleased Ava Helen and you did not come to Cambridge centres round some objects made out of clams, chopped onions and other ingredients, of which I remember eating about sixty without stopping in your house. When I thought you were coming I wondered how I could reciprocate. The only thing I knew was that when we tried to make the objects at Cambridge the result was an evil-smelling black glue which had to be relegated to the ash-can."

Victor Rothschild. Victor Rothschild to Linus Pauling. May 13, 1952.

"May I say that the only part of your speech of 6 June to which I might offer objection is your selection of the letter x, rather than some other symbol, to refer to me. In algebra, as you remember, x is used to refer to an unknown quantity - usually the letters a and ba are used to refer to known quantities. I am not, however, an unknown quantity. I have not tried to keep anything hidden in any way. I have been willing to answer any questions that the Secretary of State might care to ask me -- in fact, I have emphasized my willingness in my letters to him, which he has not answered. I wish accordingly that you had used one of the letters in the first part of the alphabet in referring to me. Let me say, however, that I have not objection to your referring to me by that name. My character has already been damaged (I would not say assassinated, because I hope that there is some chance of its being restored to full vigor); and now any statement that you make about me, referring to me by name, will be helpful to me."

Linus Pauling. Linus Pauling to Sen. Wayne Morse. June 20, 1952.

"I have read your editorial of Thursday 15 May 1952, which has the heading 'He Will Stay at Home.' I assume that you will now give your readers the benefit of a similar editorial, informing them that, although there has been no change in the situation, the State Department, less than three months later, has reversed its decision and has issued me a passport. I have not received any apology, such as was made to Professor Lattimore, but I think that the passport itself serves as an apology."

Linus Pauling. Letter to the Editor of The Dallas Morning News. July 15, 1952.

"It is disgraceful that a committee of the United States Congress should permit and even aid such a scurvy unconscionable person to cause trouble for respectable people. If Budenz is not prosecuted for perjury we must conclude that our courts and Congressional committees are not interested in learning and disclosing the truth."

Linus Pauling. "Statement by Linus Pauling." December 23, 1952.

"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 and others have been saying to the nucleic acid people at Kings, 'You had better work hard or Pauling will get interested in nucleic acids.' I would appreciate very much a copy of 'your' article. The MRC Unit would like one too. They are very interested."

Peter Pauling. Letter to Linus, Ava Helen and Crellin Pauling. January 14, 1953.

"It would be nice if your model of the seven strand cable is correct. Riley and I postulated a nearly similar arrangement for desoxyribose nucleic acid. It is conceivable that the protein cables could fit alongside of or be intermingled with the nucleic acid cables to form nucleoproteins-but I guess I'm off in the realm of fantasy."

Gerald Oster. Letter from Gerald Oster to Linus Pauling. January 26, 1953.

"First, as to the form factor of the 7-strand cable, I must say that Crick has written me that he has evaluated the form factor for a compound helix exactly. His expression is without doubt similar to the Cochran, Crick, and Vand expression for a simple helix. I have been interested, however, in approximate expression that involve less work in calculation."

Linus Pauling. Letter from Linus Pauling to Gerald Oster. January 29, 1953.

"I have read through your paper on deoxyribonucleic acid-I think that you gave me a reprint, which, however, I lost, so that I had forgotten about your work until reminded by your letter. Unless I have misunderstood this paper too, the structure that you discussed for aggregates of nucleic acid molecules did not involved 6 twisted about a seventh, but rather 6 arranged hexagonally about a seventh, and with axes parallel with that of the seventh."

Linus Pauling. Letter from Linus Pauling to Gerald Oster. January 29, 1953.

"I should be interested to know what sort of work you are carrying on at the present time. You mentioned your plan to do some work on proteins in the future; have you started on this work, or are you working on nucleic acids, or other substances?"

Linus Pauling. Letter from Linus Pauling to Gerald Oster. January 29, 1953.

"As you will see from our nucleic acid work, we considered a helical model, however, parameters can so be chosen as to fit any data. Hence, we were satisfied to choose the rod model which, at least, can be discussed more uniquely in terms of our data. Riley and I found, experimentally, a spacing of 16Å for the unhydrated nucleic acid molecule but the value is based on an extrapolation of our observed data and hence may be in error." "I am not at the present time working with the X-ray diffraction of nucleic acid. Curiously enough, my main interest is in the photochemistry of dyes in solution in an optimistic attempt to explain certain biological phenomena such as vision. My work may never help to explain these phenomena but the photochemical properties of dyes in solution are themselves fascinating."

Gerald Oster. Letter from Gerald Oster to Linus Pauling. February 3, 1953.

"I gave Watson essentially the paper on nucleic acids, and after the 12th he showed it. Morris [sic] Wilkins is supposed to be doing this work; Miss Franklin evidently is a fool. Relations are now slightly strained due to the Watson-Crick entering the field. They (W.C.) have some ideas and shall write you immediately. It is really up to them and not to me to tell you about it. We tried to build your structure, and succeeded, I think, it was pretty tight. Perhaps we should try the new one. They are getting pretty involved with their own efforts, and losing objectivity."

Peter Pauling. Letter to Linus and Ava Helen Pauling. March 14, 1953.

"We felt we could hardly omit any mention of your structure nor did we feel it reasonable to suppress our doubts about it."

James Watson Francis Crick. Letter to Linus Pauling. March 21, 1953.

"I have seen the King's College nucleic acid pictures, and talked with Watson and Crick, and I think that our structure is probably wrong, and theirs right."

Linus Pauling. Letter to Ava Helen Pauling. April 6, 1953.

"So much good work has come from the Medical Research Council unit in Cambridge under Perutz and Kendrew that I think it deserves the recognition of a Nobel Prize. I have drafted a form of recommendation and I am enclosing the draft for your comments. I need hardly say how much strength would be lent to it if you felt able to give your support. The two main things are the body of work by Perutz and Kendrew which may now be fairly claimed to have succeeded in getting out the structure of two protein molecules, and incidentally shows how large a part of your d helix plays in it; and in the second place there is the work on nucleic acid by Watson and Crick. Each of these, it seems to me, is of Nobel Prize standard. One must also take into consideration a number of other important contributions from the laboratory, such as the work on virus, on sickle-cell anaemia, the beginning of Huxley's work on muscle, and the work on collagen; it is an impressive record. As an alternative I thought it might be well to suggest that the work of the unit as a whole should be recognized by dividing a prize between its four leaders, Perutz, Kendrew, Watson and Crick. Here I should be especially glad to have your views."

W.L. Bragg. Letter from Sir Lawrence Bragg to Linus Pauling. December 9, 1959.

"A NOTE ABOUT HONEST JIM: Today Dr. Leonard Hamilton telephoned me from New York. He has been asked by Wilkins (with whom he has worked) and Crick to arrange that a lawyer write a letter to Pusey, President of Harvard, objecting to the publication by Harvard University Press of the book Honest Jim. He asked if I would be willing to join in. I said that I would like to know what was said in the letter, abut that I did authorize that I be referred to in the letter, as well as Wilkins and Crick. I also said that I would pay part of the legal expense. This does not, however, comit [sic] me, I said, to any further action, such as a libel suit."

Linus Pauling. Linus Pauling - Note to Self. Deer Flat Ranch, Salmon Creek, Big Sur, California (typed). May 4, 1967.

"I thank your for your letter and the two new paragraphs of your preface to Watson's book. I must say that I was shocked to read [The Double Helix], perhaps one of the earlier drafts, after I had read your preface. I was indignant about the insinuation about my wife and the statements about other people, but also indignant about Watson's treatment of you. I do not think that you should give the book the support and validation that would be implied by your having written a preface, even despite your disclaimer."

Linus Pauling. Letter from Linus Pauling to Sir Lawrence Bragg (The Royal Institution). May 17, 1967.

"A good example...is the case of the alpha helix. Pauling had set up a group to do X-ray crystallography of the subunits of the proteins, and they got very precise data that enabled him to build up the whole molecule from the parameters of the subunits. As you know, he did this successfully in 1948 in London, but did nothing about it because his final picture of the alpha helix in 1948 did not agree with the X-ray diagram of the whole molecule....He then waited two years, until 1950, when the group at I.C.I. in London published the first X-ray pictures of synthetic polypeptides. These synthetic polypeptides did not have the anonymous reflection that Astbury's fixtures had had, and could be accommodated to the alpha helix; and he then published the paper. I think he was hoping to do the same thing with nucleic acids, because enough had been published on the subunits for him to do it, but he was misled by the erroneous pictures of the whole molecule."

Robert Olby. Interview with Gerald James Holton. Plenary Sessions of the Conference on Transforming Conceptions of Modern Science, Bellagio, Italy. September 1969.

"Most people believe that Wilkins could have done it, and they are sure that Pauling could have done it before Watson and Crick, had he been given the data. It is interesting that when Corey went to King's in 1952, Rosalind Franklin took him into a lab and projected the DNA pictures, but Corey was a gentleman and did not attempt to convey this information, or did not remember it precisely enough to give it to Pauling."

Robert Olby. Interview with Gerald James Holton. Plenary Sessions of the Conference on Transforming Conceptions of Modern Science, Bellagio, Italy. September 1969.

"The other point is about DNA. Pauling is very frank in telling why he did not succeed here. I thought this was an interesting example of how one's courage and willingness to put out an idea, even if you are not sure it is right, can sometimes lead to disaster....There is another aspect of the way Pauling works...his 'capacitic method.' He starts with a few postulates about the parameters and the restrictions of orientation of the subunits in a giant molecule, and from there works out pure whole molecules. This worked beautifully with polypeptides, and gave him the correct answer to what the whole molecule is like. Whereas with DNA the same procedure - using what he knew about the subunits there and building a model that fitted beautifully - did not work out."

Robert Olby. Interview with Gerald James Holton. Plenary Sessions of the Conference on Transforming Conceptions of Modern Science, Bellagio, Italy. September 1969.

"I might say that it reached a very pleasant climax at a conference that Linus Pauling had arranged to take place in Pasadena in 1953. Nowadays we would call it a workshop, on the structure of biologically important molecules: it probably wasn't attended by more than 25 or 30 people...The conference was strictly limited to structure; but in that respect, it was quite spectacular. It included Watson and Crick's account of the structure of DNA, solved six months earlier..."

Max Perutz. Interview with Horace Freeland Judson December 1970.

"...in the 1930s [Warren Weaver] had used the term molecular biology for the first time in a report of the Rockefeller Foundation. I think Warren Weaver's usage was quite significant. This was largely Warren Weaver's idea, that the time had come when a more basic attack ought to be made on the problem of life, in the field of biology and medicine."

Linus Pauling. Linus Pauling oral history interview, American Philosophical Society. March 1, 1971.

Question: How competitive about the double helix of DNA? "Well, we weren't working very hard at it; we-I was using -we had really very little in the way of our own experimental data, a few rather poor x-ray photographs of DNA, not carefully prepared. I wasn't putting much of my time on determining the structure. I thought that I would get it worked out, you know, in a question of time; I didn't know that there was competition, that is, I wasn't involved in a race."

Linus Pauling. Linus Pauling oral history interview, American Philosophical Society. March 1, 1971.

"...it was Wilkins' experimental work that put Watson and Crick on the right track."

Linus Pauling. Linus Pauling oral history interview, American Philosophical Society. March 1, 1971.

"[Using Robley Williams's] density, I calculated the number of polynucleotide chains per unit to be exactly three. This result surprised me, because I had expected the value two if the nucleic acid fibres really represented genes. I decided, however, that probably the fibres were artefacts, produced by the process of extraction...I am now astonished that I began work on the triple helix structure, rather than on the double helix."

Linus Pauling. "The Molecular Basis of Biological Specificity" Nature, 248: 771. 1974.

"Mrs. Shipley, I think, was a scoundrel of the deepest dye."

Linus Pauling. NOVA Interview. 1977.

"In [The Double Helix, Watson] tells about how happy they were, he and Crick, that my husband was not allowed to come because had he come, he would no doubt have seen these excellent photographs that Rosalind Franklin made and had and which, when they saw them, with their other data, they were able to work out the structure of DNA...[If] ever there was a woman who was mistreated, it was Rosalind Franklin, and she didn't get the notice that she should have gotten for her work on DNA."

Ava Helen Pauling. Interview with Lee Herzenberg. September 1977.

"So far as I could make out, they wanted, unencumbered by any knowledge of the chemistry involved, to fit DNA into a helix. The main reason seemed to be Pauling's alpha-helix model of a protein....I told them all I knew. If they had heard before about the pairing rules, they concealed it. But as they did not seem to know much about anything, I was not unduly surprised. I mentioned our early attempts to explain the complementarity relationships by the assumption that, in the nucleic acid chain, adenylic was always next to thymidylic acid and cytidylic next to guanylic acid....I believe that the double-stranded model of DNA came about as a consequence of our conversation; but such things are only susceptible of a later judgment...."

Erwin Chargaff. Heraclitean Fire. 1978.

"In the same way, I might have discovered the double helix if I had concluded from the experimental evidence that the molecule contained two polynucleotide chains rather than three."

Linus Pauling. Letter from Linus Pauling to Dr. Robert Paradowski. November 6, 1978.

"The glib assumption that he could have come up with it - Pauling just didn't try. He can't really have spent five minutes on the problem himself. He can't have looked closely at the details of what they did publish on base pairing, in that paper; almost all the details are simply wrong"

Maurice Wilkins. The Eighth Day of Creation. 1979.

"[Pauling] didn't deserve to get the structure. He really didn't read the literature. And he didn't talk to anyone either. He'd even forgotten his own paper with Max Delbrück which said that a gene should replicate by complementarity. He seems to consider that he should have got the structure because he was so bright, but really he didn't deserve it."

James Watson. Nature, 302: 653. April 1983.

"Nature did celebrate twenty-one years, and that was really nice, because Francis [Crick] wrote and, in particular, Linus [Pauling] wrote. But we couldn't sell the twenty-fifth anniversary very big, because we were still mad at each other."

James Watson. James Watson quoted in Nature, 302, 21 (April 1983): 654. April 1983.

Omni: Surely great men, even today, don't watch much TV or hang on the telephone? "There are no such men today. We have created a mechanism that makes it practically impossible for a real genius to appear. In my own field the biochemist Fritz Lipmann or the much maligned Linus Pauling were very talented people. But generally, geniuses everywhere seem to have died out by 1914. Today, most are mediocrities blown up by the winds of the time."

Erwin Chargaff. Interview with Erwin Chargaff, OMNI, 7, no. 9 (June 1985): 128. June 1985.

"Another statement by Watson, in the candid tradition of The Double Helix, throws a good deal of light on a major source of controversy, the 15-year deadline. The rationale is no longer the need to give those slaving on its repetitive tasks the chance to see the final fruits. Instead, "to me it is crucial that we get the human genome now rather than twenty years from now, because I might be dead then and I don't want miss out on learning how life works". (Emphasis added). [To which Pauling has written on the page "This is how I felt in 1929"]

. Review of The Code of Codes. Scientific and Social Issues in the Human Genome Project. Daniel J. Kevles and Leroy Hood, Eds. Science, 257 (August 14, 1992): 981. August 14, 1992.

"Constantly exposing your ideas to informed criticism is very important, and I would venture to say that one reason both of our chief competitors failed to reach the Double Helix before us was that each was effectively very isolated. Rosalind Franklin found small talk awkward and until it was too late did not realize how much good advice Francis would willingly have given her. Had she started to talk to him, Francis would have led her to use her facts to find the base pairs. And then there's Linus Pauling. Linus' fame had gotten himself into a position where everyone was afraid to disagree with him. The only person he could freely talk to was his wife, who reinforced his ego, which isn't what you need in this life."

James Watson. James Watson, "Succeeding in Science: Some Rules of Thumb", Science, 261, 24 (September 1993): 1812. September 1993.

"My sometimes ambivalent feelings toward Linus over the past 40 years would have been very different if the facts in Hager's book had been more widely known earlier. All in all, Linus was a very mortal God."

James Watson. Letter from James D. Watson to Bob Bender (Vice-President and Senior Editor, Simon & Schuster) (letterhead of Cold Spring Harbor Laboratory). September 27, 1995.

"Let's just start with the Pauling thing. There's a myth which is, you know, that Francis and I basically stole the structure from the people at King's. I was shown Rosalind Franklin's x-ray photograph and, Whooo! that was a helix, and a month later we had the structure, and Wilkins should never have shown me the thing. I didn't go into the drawer and steal it, it was shown to me, and I was told the dimensions, a repeat of 34 angstroms, so, you know, I knew roughly what it meant and, uh, but it was that the Franklin photograph was the key event. It was, psychologically, it mobilised us..."

James Watson. James Watson, Center for Genomic Research Inauguration, Harvard. September 30, 1999.

"Pauling's textbook on the chemical bond changed the way scientists thought about chemistry, presenting chemistry as a disciplinary field unified by an underlying theory. By demonstrating how the characteristics of the chemical bond determined the structure of molecules and how the structure of molecules determined their properties, Pauling showed for the first time, as Max Perutz said, 'that chemistry could be understood rather than being memorized.'"

Mary Jo Nye. "Was Linus Pauling a Revolutionary Chemist?" Bulletin for the History of Chemistry, 25: 76-77. 2000.

"Linus Pauling had come to Corvallis, and I, along with Verner Shomaker, had driven him back to his hotel. We were talking about the structure of DNA and Pauling simply said, 'When I was looking at that structure it never occurred to me that x-ray photograph that I was looking at, the very poor one, could have been of a wet crystal. My inability to fit the density of the crystal with only two helices was because it required more mass in the unit cell, and therefore I struggled to do that with three strands. It never occurred to me that the crystal could have been wet and that the extra density had to do with water.'"

Ken Hedberg. Ken Hedberg, OSU Professor Emeritus, on an incident ca. 1969. September 25, 2002.