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ving millions of flies （onebiographer says billions； though that is probably an exaggeration）； each of which had to becaptured with tweezers and examined under a jeweler鈥檚 glass for any tiny variations ininheritance。 for six years they tried to produce mutations by any means they could think of鈥攝apping the flies with radiation and x…rays； rearing them in bright light and darkness； bakingthem gently in ovens； spinning them crazily in centrifuges鈥攂ut nothing worked。 morgan wason the brink of giving up when there occurred a sudden and repeatable mutation鈥攁 fly thathad white eyes rather than the usual red ones。 with this breakthrough； morgan and hisassistants were able to generate useful deformities； allowing them to track a trait throughsuccessive generations。 by such means they could work out the correlations betweenparticular characteristics and individual chromosomes； eventually proving to more or lesseveryone鈥檚 satisfaction that chromosomes were at the heart of inheritance。
the problem； however； remained the next level of biological intricacy： the enigmatic genesand the dna that posed them。 these were much trickier to isolate and understand。 aslate as 1933； when morgan was awarded a nobel prize for his work； many researchers stillweren鈥檛 convinced that genes even existed。 as morgan noted at the time； there was noconsensus 鈥渁s to what the genes are鈥攚hether they are real or purely fictitious。鈥潯t may seemsurprising that scientists could struggle to accept the physical reality of something sofundamental to cellular activity； but as wallace； king； and sanders point out in biology： thescience of life （that rarest thing： a readable college text）； we are in much the same positiontoday with mental processes such as thought and memory。 we know that we have them； ofcourse； but we don鈥檛 know what； if any； physical form they take。 so it was for the longest timewith genes。 the idea that you could pluck one from your body and take it away for study wasas absurd to many of morgan鈥檚 peers as the idea that scientists today might capture a straythought and examine it under a microscope。
what was certainly true was that something associated with chromosomes was directingcell replication。 finally； in 1944； after fifteen years of effort； a team at the rockefellerinstitute in manhattan； led by a brilliant but diffident canadian named oswald avery；succeeded with an exceedingly tricky experiment in which an innocuous strain of bacteria wasmade permanently infectious by crossing it with alien dna； proving that dna was far morethan a passive molecule and almost certainly was the active agent in heredity。 the austrian…born biochemist erwin chargaff later suggested quite seriously that avery鈥檚 discovery wasworth two nobel prizes。
unfortunately； avery was opposed by one of his own colleagues at the institute； a strong…willed and disagreeable protein enthusiast named alfred mirsky； who did everything in hispower to discredit avery鈥檚 work鈥攊ncluding； it has been said； lobbying the authorities at thekarolinska institute in stockholm not to give avery a nobel prize。 avery by this time wassixty…six years old and tired。 unable to deal with the stress and controversy； he resigned hisposition and never went near a lab again。 but other experiments elsewhere overwhelminglysupported his conclusions； and soon the race was on to find the structure of dna。
had you been a betting person in the early 1950s； your money would almost certainly havebeen on linus pauling of caltech； america鈥檚 leading chemist； to crack the structure of dna。
pauling was unrivaled in determining the architecture of molecules and had been a pioneer inthe field of x…ray crystallography； a technique that would prove crucial to peering into theheart of dna。 in an exceedingly distinguished career； he would win two nobel prizes （for chemistry in 1954 and peace in 1962）； but with dna he became convinced that the structurewas a triple helix； not a double one； and never quite got on the right track。 instead； victory fellto an unlikely quartet of scientists in england who didn鈥檛 work as a team； often weren鈥檛 onspeaking terms； and were for the most part novices in the field。
of the four； the nearest to a conventional boffin was maurice wilkins； who had spent muchof the second world war helping to design the atomic bomb。 two of the others； rosalindfranklin and francis crick； had passed their war years working on mines for the britishgovernment鈥攃rick of the type that blow up； franklin of the type that produce coal。
the most unconventional of the foursome was james watson； an american prodigy whohad distinguished himself as a boy as a member of a highly popular radio program called thequiz kids （and thus could claim to be at least part of the inspiration for some of the membersof the glass family in franny and zooey and other works by j。 d。 salinger） and who hadentered the university of chicago aged just fifteen。 he had earned his ph。d。 by the age oftwenty…two and was now attached to the famous cavendish laboratory in cambridge。 in1951； he was a gawky twenty…three…year…old with a strikingly lively head of hair that appearsin photographs to be straining to attach itself to some powerful magnet just out of frame。
crick； twelve years older and still without a doctorate； was less memorably hirsute andslightly more tweedy。 in watson鈥檚 account he is presented as blustery； nosy； cheerfullyargumentative； impatient with anyone slow to share a notion； and constantly in danger ofbeing asked to go elsewhere。 neither was formally trained in biochemistry。
their assumption was that if you could determine the shape of a dna molecule you wouldbe able to see鈥攃orrectly； as it turned out鈥攈ow it did what it did。 they hoped to achieve this；it would appear； by doing as little work as possible beyond thinking； and no more of that thanwas absolutely necessary。 as watson cheerfully （if a touch disingenuously） remarked in hisautobiographical book the double helix； 鈥渋t was my hope that the gene might be solvedwithout my learning any chemistry。鈥潯hey weren鈥檛 actually assigned to work on dna； and atone point were ordered to stop it。 watson was ostensibly mastering the art of crystallography；crick was supposed to be pleting a thesis on the x…ray diffraction of large molecules。
although crick and watson enjoy nearly all the credit in popular accounts for solving themystery of dna； their breakthrough was crucially dependent on experimental work done bytheir petitors； the results of which were obtained 鈥渇ortuitously；鈥潯n the tactful words of thehistorian lisa jardine。 far ahead of them； at least at the beginning； were two academics atking鈥檚 college in london； wilkins and franklin。
the new zealand鈥揵orn wilkins was a retiring figure； almost to the point of invisibility。 a1998 pbs documentary on the discovery of the structure of dna鈥攁 feat for which he sharedthe 1962 nobel prize with crick and watson鈥攎anaged to overlook him entirely。
the most enigmatic character of all was franklin。 in a severely unflattering portrait；watson in the double helix depicted franklin as a woman who was unreasonable； secretive；chronically uncooperative； and鈥攖his seemed especially to irritate him鈥攁lmost willfullyunsexy。 he allowed that she 鈥渨as not unattractive and might have been quite stunning had shetaken even a mild interest in clothes；鈥潯ut in this she disappointed all expectations。 she didn鈥檛 even use lipstick； he noted in wonder； while her dress sense 鈥渟howed all the imagination ofenglish blue…stocking adolescents。鈥�
1however； she did have the best images in existence of the possible structure of dna；achieved by means of x…ray crystallography； the technique perfected by linus pauling。
crystallography had been used successfully to map atoms in crystals （hence鈥渃rystallography鈥潱弧ut dna molecules were a much more finicky proposition。 only franklinwas managing to get good results from the process； but to wilkins鈥檚 perennial exasperationshe refused to share her findings。
if franklin was not warmly forthing with her findings； she cannot be altogetherblamed。 female academics at king鈥檚 in the 1950s were treated with a formalized disdain thatdazzles mode