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Publicado por Methuen & Co. Ltd., 1974
Librería: Windows Booksellers, Eugene, OR, Estados Unidos de America
Miembro de asociación: CBA
Hardcover, no dust jacket. Ex-library, rebound in blue library buckram. 272 pp.
Publicado por United States Department of Energy, Washington, D.C., 1999
Librería: BASEMENT BOOKS, Albuquerque, NM, Estados Unidos de America
Miembro de asociación: IOBA
Original o primera edición
Soft cover. Condición: Near Fine. 1st Edition. DOE/MA-0001. First Edition, First Printing, January 1999. Soft cover 4to in stapled wraps. Near Fine. Wraps rubbed and edgeworn w/ staple pulls, else Fine and unmarked. 66pp inc. Project Chart, Select Bibliography, Chronology; illustrated in photos and drawings, maps. Book.
Publicado por Independently Published, 2023
ISBN 10: 1998295427ISBN 13: 9781998295425
Librería: PBShop.store US, Wood Dale, IL, Estados Unidos de America
Libro Impresión bajo demanda
PAP. Condición: New. New Book. Shipped from UK. THIS BOOK IS PRINTED ON DEMAND. Established seller since 2000.
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Nuevo desde EUR 17,15
Publicado por University of Illinois Press, 1987
ISBN 10: 0252014065ISBN 13: 9780252014062
Librería: Better World Books, Mishawaka, IN, Estados Unidos de America
Libro Original o primera edición
Condición: Good. 1st Edition. Former library book; may include library markings. Used book that is in clean, average condition without any missing pages.
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Nuevo desde EUR 80,61
Usado desde EUR 18,86
Encuentre también Tapa dura Original o primera edición
Publicado por Rocket Science Institute, Inc., 2006
Librería: books4u31, Asheville, NC, Estados Unidos de America
Libro
Paperback. Condición: Vol 1. 2006 Vol 1 paperback no marks and is in very good conditionAND AS ALWAYS SHIPPED IN 24 HOURS; and emailed to you a USPS tracking number on all orders; all books are sanitized and cleaned for your protection before mailing. PLEASE NOTE OVER SEAS BUYERS if the book extra large or heavy there will be additional postage due to the new US Postage rates.
Publicado por United States Department of Energy, Washington, D.C., 2006
Librería: Take Five Books, Ashland, OR, Estados Unidos de America
Libro
Soft cover. Condición: Very Good-. Edition Not Stated. Edge wear and creases to cover, 1/2" tear to bottom front. Expedited or International shipping may cost more. Signed by Previous Owner.
Publicado por U. S. Dept. Of Energy, Washington, D.C., U.S.A., 2005
Librería: M & M Books, ATHENS, GA, Estados Unidos de America
Libro
Paperback. Condición: Near Fine. No Jacket. 2005 Edition.
Publicado por History Division Dept. of Energy, Wash - GPO, 2000
Librería: Jeff Stark, Barstow, CA, Estados Unidos de America
Libro
Hardback. Condición: Fine. Fine and birght looks new in its hardcover and gilt decorated binding. Fully illlustrated. Kind of fascinating history.
Año de publicación: 1987
Librería: Xerxes Fine and Rare Books and Documents, Glen Head, NY, Estados Unidos de America
Condición: Fine. Urbana 1987 1st University of Illinois. Neurasthenia and the American Medical Community 1870-1910. 8vo., 192pp., index. Fine in Fine DJ.
Publicado por University Press of the Pacific, 2005
ISBN 10: 1410224554ISBN 13: 9781410224552
Librería: PBShop.store US, Wood Dale, IL, Estados Unidos de America
Libro Impresión bajo demanda
PAP. Condición: New. New Book. Shipped from UK. THIS BOOK IS PRINTED ON DEMAND. Established seller since 2000.
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Nuevo desde EUR 31,52
Usado desde EUR 68,36
Encuentre también Tapa blanda
Publicado por CreateSpace Independent Publishing Platform, 2012
ISBN 10: 1479100374ISBN 13: 9781479100378
Librería: Lucky's Textbooks, Dallas, TX, Estados Unidos de America
Libro
Condición: New.
Publicado por University of Illinois Press, Urbana, 1987
ISBN 10: 0252014065ISBN 13: 9780252014062
Librería: Main Street Fine Books & Mss, ABAA, Galena, IL, Estados Unidos de America
Libro Original o primera edición
Hardcover. Small 4to. Tan cloth, pictorial dust jacket. xviii, 192pp. Illustrations. Fine/fine. A perfect, pristine and tight first edition.
Publicado por U.S. Department of Energy [1990], Washington, DC, 1990
Librería: Ground Zero Books, Ltd., Silver Spring, MD, Estados Unidos de America
Condición: very good. 28 cm, 66, wraps, illus., map, figures, chart, notes, bibliography, chronology. Topics covered include physics background, 1919-1939; early government support; the Manhattan Engineer District; the Manhattan Engineer District in operation; the atomic bomb and American strategy; and the Manhattan District in peacetime. Part of the U.S. Department of Energy Energy History Series.
Publicado por N.pl., Northern Arch. Survey, 1976., 1976
Librería: Antiquariaat Fragmenta Selecta, AMSTERDAM, Holanda
4to. XIII,304 p.; ills. & pls. Wrs. (A report evaluating the arch. potential of the 4 Northern counties of Cumbria, Durham, Northumberland and Tyne & Wear.) 0 gr.
Publicado por Northern Archaeological Survey, Newcastle-upon-Tyne, 1976
ISBN 10: 0905096002ISBN 13: 9780905096001
Librería: Barter Books Ltd, Alnwick, NORTH, Reino Unido
Miembro de asociación: IOBA
Libro Original o primera edición
Black laminated card cover. First Edition. 300mm x 210mm (12" x 8"). xiii, 303pp. With fold-out colour plans. Heavy item - shipping supplement may apply for overseas. VG : in very good condition without dust jacket as issued. Cover rubbed with light creasing.
Publicado por U.S. Dept. of Energy, Washington, DC, 2001
Librería: Ground Zero Books, Ltd., Silver Spring, MD, Estados Unidos de America
Condición: very good. Revised Edition. 28 cm, 66 + illus., wraps, illus., notes, bibliography, chronology, slight wear to cover edges. This revised edition contains a new feature, a gallery of photographs intended to capture the flavor of life and work at the three largest Manhattan Project locations--Oak Ridge, Hanford, and Los Alamos.
Publicado por BiblioBazaar, 2009
ISBN 10: 1115371266ISBN 13: 9781115371261
Librería: Revaluation Books, Exeter, Reino Unido
Libro Impresión bajo demanda
Paperback. Condición: Brand New. 376 pages. 8.75x5.75x0.84 inches. This item is printed on demand.
Publicado por BiblioBazaar, 2009
ISBN 10: 1115371282ISBN 13: 9781115371285
Librería: Revaluation Books, Exeter, Reino Unido
Libro Impresión bajo demanda
Paperback. Condición: Brand New. 376 pages. 10.00x7.50x0.84 inches. This item is printed on demand.
Publicado por Department of Energy, Management and Administration, Executive Secretariat, History Division, Washington, DC, 2000
Librería: Ground Zero Books, Ltd., Silver Spring, MD, Estados Unidos de America
Original o primera edición
Wraps. Condición: good. Presumed First Edition, First printing. Quarto, 95, wraps, illus., maps, endnotes, ink scribble on front cover, some wear to covers. This book was written in conjunction with the 50th anniversary commemoration of the Nevada Test Site, and represents a unique partnership between the U.S. Department of Energy's Nevada Operations Office (which provided the initial impetus for the project), the Office of Defense Programs of the Department's National Nuclear Security Administration (which provided funding for printing the history), and the History Division of the Department's Executive Secretariat (which researched and wrote the history). Gosling was a former Chief Historian for the Department of Energy and Fehner succeeded him into that position. The contents include a description and early history of the Nevada Test Site, the birth of the nuclear age, the search for a Continental Test Site, The Ranger Series, and the Legacy of the Nevada Test Site. The Nevada National Security Site, previously the Nevada Test Site (NTS), is a United States Department of Energy reservation located in southeastern Nye County, Nevada, about 65 miles northwest of the city of Las Vegas. Formerly known as the Nevada Proving Grounds, the site was established on 11 January 1951 for the testing of nuclear devices, covering approximately 1,360 square miles of desert and mountainous terrain. Nuclear weapons testing at the Nevada Test Site began with a 1-kiloton-of-TNT (4.2 TJ) bomb dropped on Frenchman Flat on 27 January 1951. During the 1950s, the mushroom clouds from the 100 atmospheric tests could be seen for almost 100 mi. St. George, Utah, received the brunt of the fallout of above-ground nuclear testing in the Yucca Flats/Nevada Test Site. Winds routinely carried the fallout of these tests directly through St. George and southern Utah. The vast majority-828 of the 928 total nuclear tests-were underground. The Nevada Test Site contains 28 areas, 1,100 buildings, 400 miles of paved roads, 300 miles of unpaved roads, ten heliports, and two airstrips. The Nevada Test Site was established as a 680-square-mile area by President Harry S. Truman on December 18, 1950, within the Nellis Air Force Gunnery and Bombing Range. The Nevada Test Site was the primary testing location of American nuclear devices from 1951 to 1992; 928 announced nuclear tests occurred there. Of those, 828 were underground. (Sixty-two of the underground tests included multiple, simultaneous nuclear detonations, adding 93 detonations and bringing the total number of NTS nuclear detonations to 1,021, of which 921 were underground.) The site is covered with subsidence craters from the testing. The NTS was the United States' primary location for tests in the 500-to-1,000 kt (2,100-to-4,200 TJ) range. 126 tests were conducted elsewhere, including most larger tests. Many of these occurred at the Pacific Proving Grounds in the Marshall Islands. . The last atmospheric test detonation at the Nevada Test Site was "Little Feller I" of Operation Sunbeam, on 17 July 1962. Although the United States did not ratify the Comprehensive Nuclear-Test-Ban Treaty, it honors the articles of the treaty, and underground testing of weapons ended as of 23 September 1992. Subcritical tests not involving a critical mass continue. One notable test shot was the "Sedan" shot of Operation Storax on 6 July 1962, a 104-kiloton-of-TNT (440 TJ) shot for Operation Plowshare, which sought to prove that nuclear weapons could be used for peaceful means in creating bays or canals. It created a crater 1,280 feet wide and 320 feet deep that can still be seen today. While there are no longer any explosive tests of nuclear weapons at the site, there is still subcritical testing, used to determine the viability of the United States' aging nuclear arsenal. Additionally, the site is the location of the Area 5 Radioactive Waste Management Complex, which sorts and stores low-level radioactive waste that is not transuranic and has a half life not longer than 20 years. The Radiological/Nuclear WMD Incident Exercise Site (T-1), which replicates multiple terrorist radiological incidents with train, plane, automobile, truck, and helicopter props is located in Area 1, at the former site of tests EASY, SIMON, APPLE-2, and GALILEO.
Publicado por Northern Archaeological Survey, 1976
ISBN 10: 0905096002ISBN 13: 9780905096001
Librería: M and M Books, Barkway, HERTS, Reino Unido
Libro
Soft cover. Condición: Good. 304pp. Many folding maps etc. Some creasing and edgewear to covers.
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Usado desde EUR 35,26
Encuentre también Original o primera edición
Publicado por CreateSpace Independent Publishing Platform, 2006
ISBN 10: 1463739044ISBN 13: 9781463739041
Librería: Wonder Book, Frederick, MD, Estados Unidos de America
Libro
Condición: Very Good. Very Good condition. Volume 1. (nuclear weapons, research) A copy that may have a few cosmetic defects. May also contain light spine creasing or a few markings such as an owner's name, short gifter's inscription or light stamp. Bundled media such as CDs, DVDs, floppy disks or access codes may not be included.
Publicado por United States Department of Energy
Librería: Wonder Book, Frederick, MD, Estados Unidos de America
Condición: Very Good. Very Good condition. (nevada, nevada national security site ) A copy that may have a few cosmetic defects. May also contain light spine creasing or a few markings such as an owner's name, short gifter's inscription or light stamp. Bundled media such as CDs, DVDs, floppy disks or access codes may not be included.
Publicado por U S DEPARTMENT OF ENERGY, USA, 1990
Librería: HISTOLIB - SPACETATI, AIX-VILLEMAUR-PALIS, Francia
Libro
AGRAFE. Condición: Satisfaisant. Format:21,5/28 U.S DEPARTMENT OF ENERGY, OFFICE OF ADMINISTRATION AND RESOURCES MANAGMENT, EXECUTIVE SECRETARIAT, HISTORY DIVISION DOE/MA-0417P EX BOOK OF LIBRARY WITH MARKS AND STAMPS.
Publicado por US .GOVERNMENT PRINTING OFFICE ., 1999
Librería: HISTOLIB - SPACETATI, AIX-VILLEMAUR-PALIS, Francia
Libro
Couverture souple. Condición: Satisfaisant.
Publicado por Macmillian & Sons, London, 1951
Librería: Atticus Rare Books, West Branch, IA, Estados Unidos de America
Original o primera edición
1st Edition. FIRST EDITION OF A NUMBER OF IMPORTANT PAPERS. ALSO INCLUDED: Armenteros, R.; Barker, K. H. "Decay of Neutral V-Particles" WITH Mackay, D. M., Calculating Machines and Human Thought WITH Bragg, W. L. Elimination of the Unwanted Image in Diffraction Microscopy WITH Martyn, D. G. The Theory of Magnetic Storms and Auroras. CONDITION & DETAILS: London: Macmillian & Sons. Complete volume. 4to (10.25.x 7.5 inches; 256 x 186mm). 1076 pp. & lv name and title index. Ex-libris bearing only discrete stamps on the flyleaf, pastedown and title page; no spine markings whatsoever. Bound in blue cloth, gilt-lettered at the spine. Solidly and tightly bound; light rubbing at the edges. Very clean inside and out. Very good condition.
Publicado por U. S. Department of Energy, Washington DC, 2006
Librería: Ground Zero Books, Ltd., Silver Spring, MD, Estados Unidos de America
Original o primera edición
Wraps. Condición: As new, in shrinkwrap. Presumed First Edition, First printing. vii, [1], 244 pages. Maps. Illustrations. Acronyms and Abbreviations. Endnotes. This work was written in conjunction with the opening of the Atomic Testing Museum in Las Vegas, Nevada. This was a joint project of the Department of Energy Office of History and Heritage Resources and the National Nuclear Security Administration. Since its establishment in 1957, the Office of History and Heritage Resources (OHHR) has consistently sought to maintain a level of excellence in its publications that meets all scholarly standards and yet is accessible to the general public. At the same time, OHHR has partnered with DOE program offices and field sites to provide historical products that are useful and fill specific departmental needs. In this effort, OHHR has produced a broad range of prize-winning monographs, shorter histories, articles, chronologies, and other publications. Volume II, Underground Nuclear Weapons Testing, 1957-1992 was projected but does not appear to have been completed. This is a comprehensive history of an important chapter in the history of the Cold War, American atmospheric atomic tests at the Nevada Test Site and elsewhere, providing unique insight into the successes, failures, and controversies of the program. Contents: Introduction: Operation Big Shot, April 22, 1952 * Part I: Origins of the Nevada Test Site * Part II: Early Atmospheric Testing, 1951-1952 * Part III: The Trials and Tribulations of Atmospheric Testing, 1953-1954 * Part IV: Atmospheric Testing in the Balance, 1955-1956 * Part V: Atmospheric Testing Comes to a Close, 1957-1958 * Epilogue: From Moratorium to Atmospheric Test Ban Treaty, 1958-1963 * Appendix: United States Nuclear Tests, 1945-1958. From 1951 through 1958, the United States conducted 120 tests at the Nevada Test Site. These tests directly contributed to the creation and manufacture of bigger, smaller, better, and safer nuclear weapons that greatly enhanced the capabilities of the nation's security forces and helped deter an all-out hot war.
Publicado por U. S. Department of Energy, Washington DC, 2006
Librería: Ground Zero Books, Ltd., Silver Spring, MD, Estados Unidos de America
Original o primera edición Ejemplar firmado
Hardcover. Condición: Very good. Presumed First Edition, First printing. vii, [1], 244 pages. Maps. Illustrations. Acronyms and Abbreviations. Endnotes. Rarely found as a handsomely bound hard copy (brown cloth with gold lettering on front and spine). Inscribed to Matt [Van Sickle] by Skip {Gosling} on fep. This work was written in conjunction with the opening of the Atomic Testing Museum in Las Vegas, Nevada. This was a joint project of the Department of Energy Office of History and Heritage Resources and the National Nuclear Security Administration. Since its establishment in 1957, the Office of History and Heritage Resources (OHHR) has consistently sought to maintain a level of excellence in its publications that meets all scholarly standards and yet is accessible to the general public. At the same time, OHHR has partnered with DOE program offices and field sites to provide historical products that are useful and fill specific departmental needs. In this effort, OHHR has produced a broad range of prize-winning monographs, shorter histories, articles, chronologies, and other publications. Volume II, Underground Nuclear Weapons Testing, 1957-1992 was projected but does not appear to have been completed. This is a comprehensive history of an important chapter in the history of the Cold War, American atmospheric atomic tests at the Nevada Test Site and elsewhere, providing unique insight into the successes, failures, and controversies of the program. Contents: Introduction: Operation Big Shot, April 22, 1952 * Part I: Origins of the Nevada Test Site * Part II: Early Atmospheric Testing, 1951-1952 * Part III: The Trials and Tribulations of Atmospheric Testing, 1953-1954 * Part IV: Atmospheric Testing in the Balance, 1955-1956 * Part V: Atmospheric Testing Comes to a Close, 1957-1958 * Epilogue: From Moratorium to Atmospheric Test Ban Treaty, 1958-1963 * Appendix: United States Nuclear Tests, 1945-1958. From 1951 through 1958, the United States conducted 120 tests at the Nevada Test Site. These tests directly contributed to the creation and manufacture of bigger, smaller, better, and safer nuclear weapons that greatly enhanced the capabilities of the nation's security forces and helped deter an all-out hot war.
Año de publicación: 1951
Librería: Scientia Books, ABAA ILAB, Arlington, MA, Estados Unidos de America
Libro Original o primera edición Ejemplar firmado
Soft cover. Condición: Very Good. 1st Edition. 7 pp. Original wrappers. Very Good. First Edition. SIGNED BY MAURICE WILKINS AND BY RAYMOND GOSLING, on the front wrapper. At a meeting of the Faraday Society in May 1950, Rudolf Signer "gave out samples of his best [DNA], and Wilkins took some home to King's. A few days later, he was preparing part of this DNA in highly viscous solution for the ultraviolet studies he was doing. Unexpectedly, he noticed that every time he touched the stuff with the tip of a glass rod and then drew the rod away, 'I had spun a very thin fibre of DNA, almost invisible, like a filament of spider web.' The fibres seemed so perfect and uniform that the molecules in them must have been neatly aligned alongside one another. Examined under a microscope, in polarized light, the fibres behaved as though they were made up of well-ordered crystals. So Wilkins took the fibres to a graduate student in the unit, Raymond Gosling, who was doing the crystallography with rams' sperm and had borrowed the use of an antiquated x-ray apparatus in a lead-lined basement of the chemistry department. Several dozen of Wilkins's fibres had to be bundled together, in a tiny tungsten-wire frame where they could be tightened like a violin bow, to constitute a large enough specimen for the soft focus of the x-ray tube. Wilkins and Gosling remembered that Bernal, fifteen years before, had got the first good x-ray patterns from protein crystals by keeping them wet. Accordingly, they maintained the DNA fibres at high humidity. They got striking patterns, with many spots, sharp and detailed, far better than ever before seen from DNA, and for the first time unmistakably from a substance in crystalline form. . . . That series of diffraction pictures taken in May or June of 1950 provided the one Wilkins showed at the meeting in Naples, a year later, that galvanized Watson's enthusiasm for DNA and x-ray crystallography" (Judson, Eighth Day of Creation, expanded ed., pp. 78-79). Olby, The Path to the Double Helix, pp. 332-35 (including an illustration taken from Wilkins and Gosling's paper). Maurice Wilkins shared the Nobel Prize in 1962 in Physiology or Medicine with Francis H. C. Crick and James D. Watson "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material." NOTE: Another copy--also signed by Wilkins and Gosling--sold for $2400 (buyer's premium included) on April 6, 2017, at the Pacific Book Auctions sale 611 (lot 239). Signed by Author(s).
Publicado por London: Macmillan & Co., 1953
Librería: Mark Westwood Books PBFA, Hay-on-Wye, HEREF, Reino Unido
Miembro de asociación: PBFA
Original o primera edición
Condición: Very good. Nature, Volume 171, No. 4356. April 25 1953. Complete weekly issue, this being the first printing of the announcement of the discovery of the structure of DNA. pp.: cclxix-cclxxviii, 709-732, xii[adverts], 733-758, cclxxix-cclxxxvi[adverts]. Stamped "Received 25 APR 1953" by the Cheshire Joint Sanatorium. A very good copy, stapled as issued.
Publicado por Fisher, Knight & Co, St. Albans, 1953
Librería: SOPHIA RARE BOOKS, Koebenhavn V, Dinamarca
Miembro de asociación: ILAB
Original o primera edición Ejemplar firmado
First edition. DISCOVERY OF THE STRUCTURE OF DNA. SIGNED BY ALL BUT ONE OF THE AUTHORS. First edition, offprint, signed by Watson, Crick, Wilkins, Gosling, Stokes & Wilson, i.e. six of the seven authors. We know of no copy signed by Franklin, and strongly doubt that any such copy exists. Furthermore this copy is, what we believe to be, just one of three copies signed by six authors. One of the most important scientific papers of the twentieth century, which "records the discovery of the molecular structure of deoxyribonucleic acid (DNA), the main component of chromosomes and the material that transfers genetic characteristics in all life forms. Publication of this paper initiated the science of molecular biology. Forty years after Watson and Crick's discovery, so much of the basic understanding of medicine and disease has advanced to the molecular level that their paper may be considered the most significant single contribution to biology and medicine in the twentieth century" (One Hundred Books Famous in Medicine, p. 362). "The discovery in 1953 of the double helix, the twisted-ladder structure of deoxyribonucleic acid (DNA), by James Watson and Francis Crick marked a milestone in the history of science and gave rise to modern molecular biology, which is largely concerned with understanding how genes control the chemical processes within cells. In short order, their discovery yielded ground-breaking insights into the genetic code and protein synthesis. During the 1970s and 1980s, it helped to produce new and powerful scientific techniques, specifically recombinant DNA research, genetic engineering, rapid gene sequencing, and monoclonal antibodies, techniques on which today's multi-billion dollar biotechnology industry is founded. Major current advances in science, namely genetic fingerprinting and modern forensics, the mapping of the human genome, and the promise, yet unfulfilled, of gene therapy, all have their origins in Watson and Crick's inspired work. The double helix has not only reshaped biology, it has become a cultural icon, represented in sculpture, visual art, jewelry, and toys" (Francis Crick Papers, National Library of Medicine, profiles./SC/Views/Exhibit/narrative/). In 1962, Watson, Crick, and Wilkins shared the Nobel Prize in Physiology or Medicine "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material." This copy is signed by all the authors except Rosalind Franklin (1920 -1958) - we have never seen or heard of a copy signed by her. In 1869, the Swiss physiological chemist Friedrich Miescher (1844-95) first identified what he called 'nuclein' inside the nuclei of human white blood cells. (The term 'nuclein' was later changed to 'nucleic acid' and eventually to 'deoxyribonucleic acid,' or 'DNA.') Miescher's plan was to isolate and characterize not the nuclein (which nobody at that time realized existed) but instead the protein components of leukocytes (white blood cells). Miescher thus made arrangements for a local surgical clinic to send him used, pus-coated patient bandages; once he received the bandages, he planned to wash them, filter out the leukocytes, and extract and identify the various proteins within the white blood cells. But when he came across a substance from the cell nuclei that had chemical properties unlike any protein, including a much higher phosphorous content and resistance to proteolysis (protein digestion), Miescher realized that he had discovered a new substance. Sensing the importance of his findings, Miescher wrote, "It seems probable to me that a whole family of such slightly varying phosphorous-containing substances will appear, as a group of nucleins, equivalent to proteins". But Miescher's discovery of nucleic acids was not appreciated by the scientific community, and his name had fallen into obscurity by the 20th century. "Researchers working on DNA in the early 1950s used the term 'gene' to mean the smallest unit of genetic information, but they did not know what a gene actually looked like structurally and chemically, or how it was copied, with very few errors, generation after generation. In 1944, Oswald Avery had shown that DNA was the 'transforming principle,' the carrier of hereditary information, in pneumococcal bacteria. Nevertheless, many scientists continued to believe that DNA had a structure too uniform and simple to store genetic information for making complex living organisms. The genetic material, they reasoned, must consist of proteins, much more diverse and intricate molecules known to perform a multitude of biological functions in the cell. "Crick and Watson recognized, at an early stage in their careers, that gaining a detailed knowledge of the three-dimensional configuration of the gene was the central problem in molecular biology. Without such knowledge, heredity and reproduction could not be understood. They seized on this problem during their very first encounter, in the summer of 1951, and pursued it with single-minded focus over the course of the next eighteen months. This meant taking on the arduous intellectual task of immersing themselves in all the fields of science involved: genetics, biochemistry, chemistry, physical chemistry, and X-ray crystallography. Drawing on the experimental results of others (they conducted no DNA experiments of their own), taking advantage of their complementary scientific backgrounds in physics and X-ray crystallography (Crick) and viral and bacterial genetics (Watson), and relying on their brilliant intuition, persistence, and luck, the two showed that DNA had a structure sufficiently complex and yet elegantly simple enough to be the master molecule of life. "Other researchers had made important but seemingly unconnected findings about the composition of DNA; it fell to Watson and Crick to unify these disparate findings into a coherent theory of genetic transfer. The organic chemist Alexander Todd had determined t.