按键盘上方向键 ← 或 → 可快速上下翻页，按键盘上的 Enter 键可回到本书目录页，按键盘上方向键 ↑ 可回到本页顶部！
————未阅读完？加入书签已便下次继续阅读！
kelvin was one of the most extraordinary figures of the nineteenth century鈥攊ndeed of anycentury。 the german scientist hermann von helmholtz； no intellectual slouch himself； wrotethat kelvin had by far the greatest 鈥渋ntelligence and lucidity； and mobility of thought鈥潯f anyman he had ever met。 鈥渋 felt quite wooden beside him sometimes；鈥潯e added； a bit dejectedly。
the sentiment is understandable； for kelvin really was a kind of victorian superman。 hewas born in 1824 in belfast； the son of a professor of mathematics at the royal academicalinstitution who soon after transferred to glasgow。 there kelvin proved himself such aprodigy that he was admitted to glasgow university at the exceedingly tender age of ten。 bythe time he had reached his early twenties； he had studied at institutions in london and paris；graduated from cambridge （where he won the university鈥檚 top prizes for rowing andmathematics； and somehow found time to launch a musical society as well）； been elected afellow of peterhouse； and written （in french and english） a dozen papers in pure and appliedmathematics of such dazzling originality that he had to publish them anonymously for fear ofembarrassing his superiors。 at the age of twenty…two he returned to glasgow university totake up a professorship in natural philosophy； a position he would hold for the next fifty…threeyears。
in the course of a long career （he lived till 1907 and the age of eighty…three）； he wrote 661papers； accumulated 69 patents （from which he grew abundantly wealthy）； and gained renownin nearly every branch of the physical sciences。 among much else； he suggested the methodthat led directly to the invention of refrigeration； devised the scale of absolute temperaturethat still bears his name； invented the boosting devices that allowed telegrams to be sentacross oceans； and made innumerable improvements to shipping and navigation； from theinvention of a popular marine pass to the creation of the first depth sounder。 and thosewere merely his practical achievements。
his theoretical work； in electromagnetism； thermodynamics； and the wave theory of light；was equally revolutionary。
4he had really only one flaw and that was an inability to calculatethe correct age of the earth。 the question occupied much of the second half of his career； buthe never came anywhere near getting it right。 his first effort； in 1862 for an article in apopular magazine called macmillan鈥檚 ； suggested that the earth was 98 million years old； butcautiously allowed that the figure could be as low as 20 million years or as high as 400million。 with remarkable prudence he acknowledged that his calculations could be wrong if4in particular he elaborated the second law of thermodynamics。 a discussion of these laws would be a book initself； but i offer here this crisp summation by the chemist p。 w atkins； just to provide a sense of them： 〃thereare four laws。 the third of them； the second law； was recognized first； the first； the zeroth law； wasformulated last； the first law was second； the third law might not even be a law in the same sense as theothers。〃 in briefest terms； the second la states that a little energy is always wasted。 you cant have a perpetualmotion device because no matter how efficient； it will always lose energy and eventually run down。 the first lawsays that you cant create energy and the third that you cant reduce temperatures to absolute zero； there willalways be some residual warmth。 as dennis overbye notes； the three principal laws are sometimes expressedjocularly as （1） you cant win； （2） you cant break even； and （3） you cant get out of the game。
鈥渟ources now unknown to us are prepared in the great storehouse of creation鈥濃�攂ut it wasclear that he thought that unlikely。
with the passage of time kelvin would bee more forthright in his assertions and lesscorrect。 he continually revised his estimates downward； from a maximum of 400 millionyears； to 100 million years； to 50 million years； and finally； in 1897； to a mere 24 millionyears。 kelvin wasn鈥檛 being willful。 it was simply that there was nothing in physics that couldexplain how a body the size of the sun could burn continuously for more than a few tens ofmillions of years at most without exhausting its fuel。 therefore it followed that the sun and itsplanets were relatively； but inescapably； youthful。
the problem was that nearly all the fossil evidence contradicted this； and suddenly in thenineteenth century there was a lot of fossil evidence。
ww锛凤紟xia锛痵huo txt
6 SCIENCE RED IN TOOTH AND CLAW
灏彙！ｈ。。t。xt。。澶ｅ爞
in 1787； someone in new jersey鈥攅xactly who now seems to be forgotten鈥攆ound anenormous thighbone sticking out of a stream bank at a place called woodbury creek。 thebone clearly didn鈥檛 belong to any species of creature still alive； certainly not in new jersey。
from what little is known now； it is thought to have belonged to a hadrosaur； a large duck…billed dinosaur。 at the time； dinosaurs were unknown。
the bone was sent to dr。 caspar wistar； the nation鈥檚 leading anatomist； who described it ata meeting of the american philosophical society in philadelphia that autumn。 unfortunately；wistar failed pletely to recognize the bone鈥檚 significance and merely made a few cautiousand uninspired remarks to the effect that it was indeed a whopper。 he thus missed the chance；half a century ahead of anyone else； to be the discoverer of dinosaurs。 indeed； the boneexcited so little interest that it was put in a storeroom and eventually disappeared altogether。
so the first dinosaur bone ever found was also the first to be lost。
that the bone didn鈥檛 attract greater interest is more than a little puzzling； for its appearancecame at a time when america was in a froth of excitement about the remains of large； ancientanimals。 the cause of this froth was a strange assertion by the great french naturalist thete de buffon鈥攈e of the heated spheres from the previous chapter鈥攖hat living things inthe new world were inferior in nearly every way to those of the old world。 america； buffonwrote in his vast and much…esteemed histoire naturelle ； was a land where the water wasstagnant； the soil unproductive； and the animals without size or vigor； their constitutionsweakened by the 鈥渘oxious vapors鈥潯hat rose from its rotting swamps and sunless forests。 insuch an environment even the native indians lacked virility。 鈥渢hey have no beard or bodyhair；鈥潯uffon sagely confided； 鈥渁nd no ardor for the female。鈥潯heir reproductive organs were鈥渟mall and feeble。鈥�
buffon鈥檚 observations found surprisingly eager support among other writers； especiallythose whose conclusions were not plicated by actual familiarity with the country。 adutchman named eille de pauw announced in a popular work called recherchesphilosophiques sur les am茅ricains that native american males were not only reproductivelyunimposing； but 鈥渟o lacking in virility that they had milk in their breasts。鈥潯uch viewsenjoyed an improbable durability and could be found repeated or echoed in european texts tillnear the end of the nineteenth century。
not surprisingly； such aspersions were indignantly met in america。 thomas jeffersonincorporated a furious （and； unless the context is understood； quite bewildering） rebuttal in hisnotes on the state of virginia ； and induced his new hampshire friend general john sullivanto send twenty soldiers into the northern woods to find a bull moose to present to buffon asproof of the stature and majesty of american quadrupeds。 it took the men two weeks to trackdown a suitable subject。 the moose； when shot； unfortunately lacked the imposing horns thatjefferson had specified； but sullivan thoughtfully included a rack of antlers from an elk orstag with the suggestion that these be attached instead。 who in france； after all； would know？
meanwhile in philadelphia鈥攚istar鈥檚 city鈥攏aturalists had begun to assemble the bones ofa giant elephant…like creature known at first as 鈥渢he great american incognitum鈥潯ut lateridentified； not quite correctly； as a mammoth。 the first of these bones had been discovered ata place called big bone lick in kentucky； but soon others were turning up all over。 america；it appeared； had once been the home of a truly substantial creature鈥攐ne that would surelydisprove buffon鈥檚 foolish gallic contentions。
in their keenness to demonstrate the incognitum鈥檚 bulk and ferocity； the americannaturalists appear to have bee slightly carried away。 they overestimated its size by afactor of six and gave it frightening claws； which in fact came from a megalonyx； or giantground sloth； found nearby。 rather remarkably； they persuaded themselves that the animalhad enjoyed 鈥渢he agility and ferocity of the tiger；鈥潯nd portrayed it in illustrations as pouncingwith feline grace onto prey from boulders。 when tusks were discovered； they were forced intothe animal鈥檚 head in any number of inventive ways。 one restorer screwed the tusks in upsidedown； like the fangs of a saber…toothed cat； which gave it a satisfyingly aggressive aspect。
another arranged the tusks so that they curved backwards on the engaging theory that thecreature had been aquatic and had used them to anchor itself to trees while dozing。 the mostpertinent consideration about the incognitum； however； was that it appeared to be extinct鈥攁fact that buffon cheerfully seized upon as proof of its incontestably degenerate nature。
buffon died in 1788； but the controversy rolled on。 in 1795 a selection of bones made theirway to paris； where they were examined by the rising star of paleontology； the youthful andaristocratic georges cuvier。 cuvier was already dazzling people with his genius for takingheaps of disarticulated bones and whipping them into shapely forms。 it was said that he coulddescribe the look and nature of an animal from a single tooth or scrap of jaw； and often namethe species and genus into the bargain。 realizing that no one in america had thought to writea formal description of the lumbering beast； cuvier did so； and thus became its officialdiscoverer。 he called it a mastodon （which means； a touch unexpectedly； 鈥渘ipple…teeth鈥潱�
inspired by the controversy； in 1796 cuvier wrote a landmark paper； note on the species ofliving and fossil elephants； in which he put forward for the first time a formal theory ofextinctions。 his belief was that from time to time the earth experienced global catastrophes inwhich groups of creatures were wiped out。 for religious people； including cuvier himself； theidea raised unfortable implications since it suggested an unaccountable casualness on thepart of providence。 to what end would god create species only to wipe them out later？ thenotion was contrary to the belief in the great chain of being； which held that the world wascarefully ordered and that every living thing within it had a place and purpose； and always hadand always would。 jefferson for one couldn鈥檛 abide the thought that whole species would everbe permitted to vanish （or； e to that； to evolve）。 so when it was put to him that theremight be scientific and political value in sending a party to explore the interior of americabeyond the mississippi he leapt at the idea； hoping the intrepid adventurers would find herdsof healthy mastodons and other outsized creatures grazing on the bounteous plains。
jefferson鈥檚 personal secretary and trusted friend meriwether lewis was chosen co…leader andchief naturalist for the expedition。 the person selected to advise him on what to look out forwith regard to animals living and deceased was none other than caspar wistar。
in the same year鈥攊n fact； the same month鈥攖hat the aristocratic and celebrated cuvier waspropounding his extinction theories in paris； on the other side of the english channel a rathermore obscure englishman was having an insight into the value of fossils that would also havelasting ramifications。 william smith was a young supervisor of construction on the somersetcoal canal。 on the evening of january 5； 1796； he was sitting in a coaching inn in somersetwhen he jotted down the notion that would eventually make his reputation。 to interpret rocks；there needs to be some means of correlation； a basis on which you can tell that thosecarboniferous rocks from devon