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wellington； where they have remained eversince。 the iguanodon tooth that started it all—arguably the most important tooth inpaleontology—is no longer on display。
of course dinosaur hunting didn’t end with the deaths of the great nineteenth…century fossilhunters。 indeed； to a surprising extent it had only just begun。 in 1898； the year that fellbetween the deaths of cope and marsh； a trove greater by far than anything found before wasdiscovered—noticed； really—at a place called bone cabin quarry； only a few miles frommarsh’s prime hunting ground at o bluff； wyoming。 there； hundreds and hundreds offossil bones were to be found weathering out of the hills。 they were so numerous； in fact； thatsomeone had built a cabin out of them—hence the name。 in just the first two seasons； 100；000pounds of ancient bones were excavated from the site； and tens of thousands of pounds morecame in each of the half dozen years that followed。
the upshot is that by the turn of the twentieth century； paleontologists had literally tons ofold bones to pick over。 the problem was that they still didn’t have any idea how old any ofthese bones were。 worse； the agreed ages for the earth couldn’t fortably support thenumbers of eons and ages and epochs that the past obviously contained。 if earth were reallyonly twenty million years old or so； as the great lord kelvin insisted； then whole orders ofancient creatures must have e into being and gone out again practically in the samegeological instant。 it just made no sense。
other scientists besides kelvin turned their minds to the problem and came up with resultsthat only deepened the uncertainty。 samuel haughton； a respected geologist at trinity collegein dublin； announced an estimated age for the earth of 2；300 million years—way beyondanything anybody else was suggesting。 when this was drawn to his attention； he recalculatedusing the same data and put the figure at 153 million years。 john joly； also of trinity； decidedto give edmond halley’s ocean salts idea a whirl； but his method was based on so manyfaulty assumptions that he was hopelessly adrift。 he calculated that the earth was 89 millionyears old—an age that fit neatly enough with kelvin’s assumptions but unfortunately not withreality。
such was the confusion that by the close of the nineteenth century； depending on whichtext you consulted； you could learn that the number of years that stood between us and thedawn of plex life in the cambrian period was 3 million； 18 million； 600 million； 794million； or 2。4 billion—or some other number within that range。 as late as 1910； one of themost respected estimates； by the american george becker； put the earth’s age at perhaps aslittle as 55 million years。
just when matters seemed most intractably confused； along came another extraordinaryfigure with a novel approach。 he was a bluff and brilliant new zealand farm boy namedernest rutherford； and he produced pretty well irrefutable evidence that the earth was at leastmany hundreds of millions of years old； probably rather more。
remarkably； his evidence was based on alchemy—natural； spontaneous； scientificallycredible； and wholly non…occult； but alchemy nonetheless。 newton； it turned out； had not beenso wrong after all。 and exactly how that came to be is of course another story。
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7ELEMENTAL MATTERSCHEMISTRY
小？说网
as an earnest and respectable science is often said to date from 1661； whenrobert boyle of oxford published the sceptical chymist —the first work to distinguishbetween chemists and alchemists—but it was a slow and often erratic transition。 into theeighteenth century scholars could feel oddly fortable in both camps—like the germanjohann becher； who produced an unexceptionable work on mineralogy called physicasubterranea ； but who also was certain that； given the right materials； he could make himselfinvisible。
perhaps nothing better typifies the strange and often accidental nature of chemical sciencein its early days than a discovery made by a german named hennig brand in 1675。 brandbecame convinced that gold could somehow be distilled from human urine。 （the similarity ofcolor seems to have been a factor in his conclusion。） he assembled fifty buckets of humanurine； which he kept for months in his cellar。 by various recondite processes； he converted theurine first into a noxious paste and then into a translucent waxy substance。 none of it yieldedgold； of course； but a strange and interesting thing did happen。 after a time； the substancebegan to glow。 moreover； when exposed to air； it often spontaneously burst into flame。
the mercial potential for the stuff—which soon became known as phosphorus； fromgreek and latin roots meaning “light bearing”—was not lost on eager businesspeople； but thedifficulties of manufacture made it too costly to exploit。 an ounce of phosphorus retailed forsix guineas—perhaps five hundred dollars in today’s money—or more than gold。
at first； soldiers were called on to provide the raw material； but such an arrangement washardly conducive to industrial…scale production。 in the 1750s a swedish chemist named karl（or carl） scheele devised a way to manufacture phosphorus in bulk without the slop or smellof urine。 it was largely because of this mastery of phosphorus that sweden became； andremains； a leading producer of matches。
scheele was both an extraordinary and extraordinarily luckless fellow。 a poor pharmacistwith little in the way of advanced apparatus； he discovered eight elements—chlorine； fluorine；manganese； barium； molybdenum； tungsten； nitrogen； and oxygen—and got credit for none ofthem。 in every case； his finds were either overlooked or made it into publication aftersomeone else had made the same discovery independently。 he also discovered many usefulpounds； among them ammonia； glycerin； and tannic acid； and was the first to see themercial potential of chlorine as a bleach—all breakthroughs that made other peopleextremely wealthy。
scheele’s one notable shorting was a curious insistence on tasting a little of everythinghe worked with； including such notoriously disagreeable substances as mercury； prussic acid（another of his discoveries）； and hydrocyanic acid—a pound so famously poisonous that150 years later erwin schr？dinger chose it as his toxin of choice in a famous thoughtexperiment （see page 146）。 scheele’s rashness eventually caught up with him。 in 1786； agedjust forty…three； he was found dead at his workbench surrounded by an array of toxicchemicals； any one of which could have accounted for the stunned and terminal look on hisface。
were the world just and swedish…speaking； scheele would have enjoyed universal acclaim。
instead credit has tended to lodge with more celebrated chemists； mostly from the english…speaking world。 scheele discovered oxygen in 1772； but for various heartbreakingly plicated reasons could not get his paper published in a timely manner。 instead credit wentto joseph priestley； who discovered the same element independently； but latterly； in thesummer of 1774。 even more remarkable was scheele’s failure to receive credit for thediscovery of chlorine。 nearly all textbooks still attribute chlorine’s discovery to humphrydavy； who did indeed find it； but thirty…six years after scheele had。
although chemistry had e a long way in the century that separated newton and boylefrom scheele and priestley and henry cavendish； it still had a long way to go。 right up to theclosing years of the eighteenth century （and in priestley’s case a little beyond） scientistseverywhere searched for； and sometimes believed they had actually found； things that justweren’t there： vitiated airs； dephlogisticated marine acids； phloxes； calxes； terraqueousexhalations； and； above all； phlogiston； the substance that was thought to be the active agentin bustion。 somewhere in all this； it was thought； there also resided a mysterious élanvital； the force that brought inanimate objects to life。 no one knew where this ethereal essencelay； but two things seemed probable： that you could enliven it with a jolt of electricity （anotion mary shelley exploited to full effect in her novel frankenstein ） and that it existed insome substances but not others； which is why we