万物简史英文版_比尔·布莱森-第52章
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broadcasts。 their main concern； however； wasthat the shipboard winch； straining to hold on to a metal ball and two tons of steel cable；would snap and send the two men plunging to the seafloor。 in such an event； nothing couldhave saved them。
the one thing their descents didn鈥檛 produce was a great deal of worthwhile science。
although they encountered many creatures that had not been seen before； the limits ofvisibility and the fact that neither of the intrepid aquanauts was a trained oceanographer meantthey often weren鈥檛 able to describe their findings in the kind of detail that real scientistscraved。 the sphere didn鈥檛 carry an external light； merely a 250…watt bulb they could hold upto the window； but the water below five hundred feet was practically impenetrable anyway；and they were peering into it through three inches of quartz； so anything they hoped to viewwould have to be nearly as interested in them as they were in it。 about all they could report； inconsequence； was that there were a lot of strange things down there。 on one dive in 1934；beebe was startled to spy a giant serpent 鈥渕ore than twenty feet long and very wide。鈥潯tpassed too swiftly to be more than a shadow。 whatever it was； nothing like it has been seenby anyone since。 because of such vagueness their reports were generally ignored byacademics。
after their record…breaking descent of 1934； beebe lost interest in diving and moved on toother adventures； but barton persevered。 to his credit； beebe always told anyone who askedthat barton was the real brains behind the enterprise； but barton seemed unable to step fromthe shadows。 he； too； wrote thrilling accounts of their underwater adventures and even starredin a hollywood movie called titans of the deep； featuring a bathysphere and many excitingand largely fictionalized encounters with aggressive giant squid and the like。 he evenadvertised camel cigarettes （鈥渢hey don鈥檛 give me jittery nerves鈥潱！n 1948 he increased thedepth record by 50 percent； with a dive to 4；500 feet in the pacific ocean near california； butthe world seemed determined to overlook him。 one newspaper reviewer of titans of the deepactually thought the star of the film was beebe。 nowadays； barton is lucky to get a mention。
at all events； he was about to be prehensively eclipsed by a father…and…son team fromswitzerland； auguste and jacques piccard； who were designing a new type of probe called abathyscaphe （meaning 鈥渄eep boat鈥潱！hristened trieste； after the italian city in which it wasbuilt； the new device maneuvered independently； though it did little more than just go up anddown。 on one of its first dives； in early 1954； it descended to below 13；287 feet； nearly threetimes barton鈥檚 record…breaking dive of six years earlier。 but deep…sea dives required a greatdeal of costly support； and the piccards were gradually going broke。
in 1958； they did a deal with the u。s。 navy； which gave the navy ownership but left themin control。 now flush with funds； the piccards rebuilt the vessel； giving it walls five inchesthick and shrinking the windows to just two inches in diameter鈥攍ittle more than peepholes。
but it was now strong enough to withstand truly enormous pressures； and in january 1960jacques piccard and lieutenant don walsh of the u。s。 navy sank slowly to the bottom of theocean鈥檚 deepest canyon； the mariana trench； some 250 miles off guam in the western pacific（and discovered； not incidentally； by harry hess with his fathometer）。 it took just under fourhours to fall 35；820 feet； or almost seven miles。 although the pressure at that depth wasnearly 17；000 pounds per square inch； they noticed with surprise that they disturbed a bottom…dwelling flatfish just as they touched down。 they had no facilities for taking photographs； sothere is no visual record of the event。
after just twenty minutes at the world鈥檚 deepest point； they returned to the surface。 it wasthe only occasion on which human beings have gone so deep。
forty years later； the question that naturally occurs is： why has no one gone back since？ tobegin with； further dives were vigorously opposed by vice admiral hyman g。 rickover； aman who had a lively temperament； forceful views； and； most pertinently； control of thedepartmental checkbook。 he thought underwater exploration a waste of resources and pointedout that the navy was not a research institute。 the nation； moreover； was about to beefully preoccupied with space travel and the quest to send a man to the moon； which madedeep sea investigations seem unimportant and rather old…fashioned。 but the decisiveconsideration was that the trieste descent didn鈥檛 actually achieve much。 as a navy officialexplained years later： 鈥渨e didn鈥檛 learn a hell of a lot from it； other than that we could do it。
why do it again？鈥潯t was； in short； a long way to go to find a flatfish； and expensive too。
repeating the exercise today； it has been estimated； would cost at least 100 million。
when underwater researchers realized that the navy had no intention of pursuing apromised exploration program； there was a pained outcry。 partly to placate its critics； thenavy provided funding for a more advanced submersible； to be operated by the woods holeoceanographic institution of massachusetts。 called alvin； in somewhat contracted honor ofthe oceanographer allyn c。 vine； it would be a fully maneuverable minisubmarine； though itwouldn鈥檛 go anywhere near as deep as the trieste。 there was just one problem： the designerscouldn鈥檛 find anyone willing to build it。 according to william j。 broad in the universebelow： 鈥渘o big pany like general dynamics； which made submarines for the navy；wanted to take on a project disparaged by both the bureau of ships and admiral rickover； thegods of naval patronage。鈥潯ventually； not to say improbably； alvin was constructed bygeneral mills； the food pany； at a factory where it made the machines to producebreakfast cereals。
as for what else was down there； people really had very little idea。 well into the 1950s； thebest maps available to oceanographers were overwhelmingly based on a little detail fromscattered surveys going back to 1929 grafted onto； essentially an ocean of guesswork。 the navy had excellent charts with which to guide submarines through canyons and aroundguyots； but it didn鈥檛 wish such information to fall into soviet hands； so it kept its knowledgeclassified。 academics therefore had to make do with sketchy and antiquated surveys or relyon hopeful surmise。 even today our knowledge of the ocean floors remains remarkably lowresolution。 if you look at the moon with a standard backyard telescope you will seesubstantial craters鈥攆racastorious； blancanus； zach； planck； and many others familiar to anylunar scientist鈥攖hat would be unknown if they were on our own ocean floors。 we have bettermaps of mars than we do of our own seabeds。
at the surface level； investigative techniques have also been a trifle ad hoc。 in 1994； thirty…four thousand ice hockey gloves were swept overboard from a korean cargo ship during astorm in the pacific。 the gloves washed up all over； from vancouver to vietnam； helpingoceanographers to trace currents more accurately than they ever had before。
today alvin is nearly forty years old； but it still remains america鈥檚 premier research vessel。
there are still no submersibles that can go anywhere near the depth of the mariana trenchand only five； including alvin； that can reach the depths of the 鈥渁byssal plain鈥濃�攖he deepocean floor鈥攖hat covers more than half the planet鈥檚 surface。 a typical submersible costsabout 25；000 a day to operate； so they are hardly dropped into the water on a whim； still lessput to sea in the hope that they will randomly stumble on something of interest。 it鈥檚 rather asif our firsthand experience of the surface world were based on the work of five guys exploringon garden tractors after dark。 according to robert kunzig； humans may have scrutinized鈥減erhaps a millionth or a billionth of the sea鈥檚 darkness。 maybe less。 maybe much less。鈥�
but oceanographers are nothing if not industrious； and they have made several importantdiscoveries with their limited resources鈥攊ncluding； in 1977； one of the most important andstartling biological discoveries of the twentieth century。 in that year alvin found teemingcolonies of large organisms living on and around deep…sea vents off the gal谩pagos islands鈥攖ube worms over ten feet long； clams a foot wide； shrimps and mussels in profusion；wriggling spaghetti worms。 they all owed their existence to vast colonies of bacteria thatwere deriving their energy and sustenance from hydrogen sulfides鈥攑ounds profoundlytoxic to surface creatures鈥攖hat were pouring steadily from the vents。 it was a worldindependent of sunlight； oxygen； or anything else normally associated with life。 this was aliving system based not on photosynthesis but on chemosynthesis； an arrangement thatbiologists would have dismissed as preposterous had anyone been imaginative enough tosuggest it。
huge amounts of heat and energy flow from these vents。 two dozen of them together willproduce as much energy as a large power station； and the range of temperatures around themis enormous。 the temperature at the point of outflow can be as much as 760 degreesfahrenheit； while a few feet away the water may be only two or three degrees above freezing。
a type of worm called an alvinellid was found living right on the margins； with the watertemperature 140 degrees warmer at its head than at its tail。 before this it had been thought thatno plex organisms could survive in water warmer than about 130 degrees； and here wasone that was surviving warmer temperatures than that and extreme cold to boot。 thediscovery transformed our understanding of the requirements for life。
it also answered one of the great puzzles of oceanography鈥攕omething that many of usdidn鈥檛 realize was a puzzle鈥攏amely； why the oceans don鈥檛 grow saltier with time。 at the riskof stating the obvious； there is a lot of salt in the sea鈥攅nough to bury every bit of land on theplanet to a depth of about five hundred feet。 millions of gallons of fresh water evaporate from the ocean daily； leaving all their salts behind； so logically the seas ought to grow more saltywith the passing years； but they don鈥檛。 something takes an amount of salt out of the waterequivalent to the amount being put in。 for the longest time； no one could figure out whatcould be responsible for this。
alvin鈥檚 discovery of the deep…sea vents provided the answer。 geophysicists realized that thevents were acting much like the filters in a fish tank。 as water is taken down into the crust；salts are stripped from it； and eventually clean water is blown out again through the chimneystacks。 the process is not swift鈥攊t can take up to ten million years to clean an ocean鈥攂ut itis marvelously efficient as long as you are not in a hurry。
perhaps nothing speaks more clearly of our psychological remoteness from the oceandepths than that the main expressed goal for oceanographers during international geophysicalyear of 1957鈥�58 was to study 鈥渢he use of ocean depths for the dumping of radioactivewastes。鈥潯his wasn鈥檛 a secret assignment； you understand； but a proud public boast。 in
