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bove。
spring never came and summer never warmed： 1816 became known as the year withoutsummer。 crops everywhere failed to grow。 in ireland a famine and associated typhoidepidemic killed sixty…five thousand people。 in new england； the year became popularlyknown as eighteen hundred and froze to death。 morning frosts continued until june andalmost no planted seed would grow。 short of fodder； livestock died or had to be prematurelyslaughtered。 in every way it was a dreadful year—almost certainly the worst for farmers inmodern times。 yet globally the temperature fell by only about 1。5 degrees fahrenheit。 earth’snatural thermostat； as scientists would learn； is an exceedingly delicate instrument。
the nineteenth century was already a chilly time。 for two hundred years europe and northamerica in particular had experienced a little ice age； as it has bee known； whichpermitted all kinds of wintry events—frost fairs on the thames； ice…skating races along dutchcanals—that are mostly impossible now。 it was a period； in other words； when frigidity wasmuch on people’s minds。 so we may perhaps excuse nineteenth…century geologists for beingslow to realize that the world they lived in was in fact balmy pared with former epochs；and that much of the land around them had been shaped by crushing glaciers and cold thatwould wreck even a frost fair。
they knew there was something odd about the past。 the european landscape was litteredwith inexplicable anomalies—the bones of arctic reindeer in the warm south of france； hugerocks stranded in improbable places—and they often came up with inventive but not terribly plausible explanations。 one french naturalist named de luc； trying to explain how graniteboulders had e to rest high up on the limestone flanks of the jura mountains； suggestedthat perhaps they had been shot there by pressed air in caverns； like corks out of apopgun。 the term for a displaced boulder is an erratic； but in the nineteenth century theexpression seemed to apply more often to the theories than to the rocks。
the great british geologist arthur hallam has suggested that if james hutton； the father ofgeology； had visited switzerland； he would have seen at once the significance of the carvedvalleys； the polished striations； the telltale strand lines where rocks had been dumped； and theother abundant clues that point to passing ice sheets。 unfortunately； hutton was not a traveler。
but even with nothing better at his disposal than secondhand accounts； hutton rejected out ofhand the idea that huge boulders had been carried three thousand feet up mountainsides byfloods—all the water in the world won’t make a boulder float； he pointed out—and becameone of the first to argue for widespread glaciation。 unfortunately his ideas escaped notice； andfor another half century most naturalists continued to insist that the gouges on rocks could beattributed to passing carts or even the scrape of hobnailed boots。
local peasants； uncontaminated by scientific orthodoxy； knew better； however。 thenaturalist jean de charpentier told the story of how in 1834 he was walking along a countrylane with a swiss woodcutter when they got to talking about the rocks along the roadside。 thewoodcutter matter…of…factly told him that the boulders had e from the grimsel； a zone ofgranite some distance away。 “when i asked him how he thought that these stones had reachedtheir location； he answered without hesitation： ‘the grimsel glacier transported them on bothsides of the valley； because that glacier extended in the past as far as the town of bern。’ ”
charpentier was delighted。 he had e to such a view himself； but when he raised thenotion at scientific gatherings； it was dismissed。 one of charpentier’s closest friends wasanother swiss naturalist； louis agassiz； who after some initial skepticism came to embrace；and eventually all but appropriate； the theory。
agassiz had studied under cuvier in paris and now held the post of professor of naturalhistory at the college of neuchatel in switzerland。 another friend of agassiz’s； a botanistnamed karl schimper； was actually the first to coin the term ice age （in german eiszeit ）； in1837； and to propose that there was good evidence to show that ice had once lain heavilyacross not just the swiss alps； but over much of europe； asia； and north america。 it was aradical notion。 he lent agassiz his notes—then came very much to regret it as agassizincreasingly got the credit for what schimper felt； with some legitimacy； was his theory。
charpentier likewise ended up a bitter enemy of his old friend。 alexander von humboldt； yetanother friend； may have had agassiz at least partly in mind when he observed that there arethree stages in scientific discovery： first； people deny that it is true； then they deny that it isimportant； finally they credit the wrong person。
at all events； agassiz made the field his own。 in his quest to understand the dynamics ofglaciation； he went everywhere—deep into dangerous crevasses and up to the summits of thecraggiest alpine peaks； often apparently unaware that he and his team were the first to climbthem。 nearly everywhere agassiz encountered an unyielding reluctance to accept his theories。
humboldt urged him to return to his area of real expertise； fossil fish； and give up this madobsession with ice； but agassiz was a man possessed by an idea。
agassiz’s theory found even less support in britain； where most naturalists had never seena glacier and often couldn’t grasp the crushing forces that ice in bulk exerts。 “could scratches and polish just be due to ice ？” asked roderick murchison in a mocking tone at one meeting；evidently imagining the rocks as covered in a kind of light and glassy rime。 to his dying day；he expressed the frankest incredulity at those “ice…mad” geologists who believed that glacierscould account for so much。 william hopkins； a cambridge professor and leading member ofthe geological society； endorsed this view； arguing that the notion that ice could transportboulders presented “such obvious mechanical absurdities” as to make it unworthy of thesociety’s attention。
undaunted； agassiz traveled tirelessly to promote his theory。 in 18