mc.theandromedastrein- 第36部分

　
　　　But　enzymes　had　a　further　use。　They　made　possible　chemical　reactions　that　otherwise　would　not　occur。　A　biochemist　could　duplicate　the　reactions　by　using　great　heat；　or　great　pressure；　or　strong　acids。　But　the　human　body；　or　the　individual　cell；　could　not　tolerate　such　extremes　of　environment。　Enzymes；　the　matchmakers　of　life；　helped　chemical　reactions　to　go　forward　at　body　temperature　and　atmospheric　pressure。
　
　　　Enzymes　were　essential　to　life　on　earth。　But　if　another　form　of　life　had　learned　to　do　without　them；　it　must　have　evolved　in　a　wholly　different　way。
　
　　　Therefore；　they　were　dealing　with　an　entirely　alien　organism。
　
　　　And　this　in　turn　meant　that　analysis　and　neutralization　would　take　much；　much　longer。
　
　　　***
　
　　　In　the　room　marked　MORPHOLOGY；　Jeremy　Stone　removed　the　small　plastic　capsule　in　which　the　green　fleck　had　been　imbedded。　He　set　the　now…hard　capsule　into　a　vise；　fixing　it　firmly；　and　then　took　a　dental　drill　to　it；　shaving　away　the　plastic　until　he　exposed　bare　green　material。
　
　　　This　was　a　delicate　process；　requiring　many　minutes　of　concentrated　work。　At　the　end　of　that　time；　he　had　shaved　the　plastic　in　such　a　way　that　he　had　a　pyramid　of　plastic；　with　the　green　fleck　at　the　peak　of　the　pyramid。
　
　　　He　unscrewed　the　vise　and　lifted　the　plastic　out。　He　took　it　to　the　microtome；　a　knife　with　a　revolving　blade　that　cut　very　thin　slices　of　plastic　and　imbedded　green　tissue。　These　slices　were　round；　they　fell　from　the　plastic　block　into　a　dish　of　water。　The　thickness　of　the　slice　could　be　measured　by　looking　the　light　as　it　reflected　off　the　slices　if　the　light　was　faint　silver；　the　slice　was　too　thick。　If；　on　the　other　hand；　it　was　a　rainbow　of　colors；　then　it　was　the　right　thickness；　just　a　few　molecules　in　depth。
　
　　　That　was　how　thick　they　wanted　a　slice　of　tissue　to　be　for　the　electron　microscope。
　
　　　When　Stone　had　a　suitable　piece　of　tissue；　he　lifted　it　carefully　with　forceps　and　set　it　onto　a　small　round　copper　grid。　This　in　turn　was　inserted　into　a　metal　button。　Finally；　the　button　was　set　into　the　electron　microscope；　and　the　microscope　sealed　shut。
　
　　　The　electron　microscope　used　by　Wildfire　was　the　BVJ　model　JJ…42。　It　was　a　high…intensity　model　with　an　image　resolution　attachment。　In　principle；　the　electron　microscope　was　simple　enough：　it　worked　exactly　like　a　light　microscope；　but　instead　of　focusing　light　rays；　it　focused　an　electron　beam。　Light　is　focused　by　lenses　of　curved　glass。　Electrons　are　focused　by　magnetic　fields。
　
　　　In　many　respects；　the　EM　was　not　a　great　deal　different　from　television；　and　in　fact；　the　image　was　displayed　on　a　television　screen；　a　coated　surface　that　glowed　when　electrons　struck　it。　The　great　advantage　of　the　electron　microscope　was　that　it　could　magnify　objects　far　more　than　the　light　microscope。　The　reason　for　this　had　to　do　with　quantum　mechanics　and　the　waveform　theory　of　radiation。　The　best　simple　explanation　had　e　from　the　electron　microscopist　Sidney　Polton；　also　a　racing　enthusiast。
　
　　　〃Assume；〃　Polton　said；　〃that　you　have　a　road；　with　a　sharp　corner。　Now　assume　that　you　have　two　automobiles；　a　sports　car　and　a　large　truck。　When　the　truck　tries　to　go　around　the　corner；　it　slips　off　the　road；　but　the　sports　car　manages　it　easily。　Why？　The　sports　car　is　lighter；　and　smaller；　and　faster；　it　is　better　suited　to　tight；　sharp　curves。　On　large；　gentle　curves；　the　automobiles　will　perform　equally　well；　but　on　sharp　curves；　the　sports　car　will　do　better。
　
　　　〃In　the　same　way；　an　electron　microscope　will　'hold　the　road'　better　than　a　light　microscope。　All　objects　are　made　of　corners；　and　edges。　The　electron　wavelength　is　smaller　than　the　quantum　of　light。　It　cuts　the　corners　closer；　follows　the　road　better；　and　outlines　it　more　precisely。　With　a　light　microscope　like　a　truck　you　can　follow　only　a　large　road。　In　microscopic　terms　this　means　only　a　large　object；　with　large　edges　and　gentle　curves：　cells；　and　nuclei。　But　an　electron　microscope　can　follow　all　the　minor　routes；　the　byroads；　and　can　outline　very　small　structures　within　the　cell　mitochondria；　ribosomes；　membranes；　reticula。〃
　
　　　In　actual　practice　there　were　several　drawbacks　to　the　electron　microscope；　which　counterbalanced　its　great　powers　of　magnification。　For　one　thing；　because　it　used　electrons　instead　of　light；　the　inside　of　the　microscope　had　to　be　a　vacuum。　This　meant　it　was　impossible　to　examine　living　creatures。
　
　　　But　the　most　serious　drawback　had　to　do　with　the　sections　of　specimen。　These　were　extremely　thin；　making　it　difficult　to　get　a　good　three…dimensional　concept　of　the　object　under　study。
　
　　　Again；　Polton　had　a　simple　analogy。　〃Let　us　say　you　cut　an　automobile　in　half　down　the　middle。　In　that　case；　you　could　guess　the　plete；　'whole'　structure。　But　if　you　cut　a　very　thin　slice　from　the　automobile；　and　if　you　cut　it　on　a　strange　angle；　it　could　be　more　difficult。　In　your　slice；　you　might　have　only　a　bit　of　bumper；　and　rubber　tire；　and　glass。　From　such　a　slice；　it　would　be　hard　to　guess　the　shape　and　function　of　the　full　structure。〃
　
　　　Stone　was　aware　of　all　the　drawbacks　as　he　fitted　the　metal　button　into　the　EM；　sealed　it　shut；　and　started　the　vacuum　pump。　He　knew　the　drawbacks　and　he　ignored　them；　because　he　had　no　choice。　Limited　as　it　was；　the　electron　microscope　was　their　only　available　high…power　tool。
　
　　　He　turned　down　the　room　lights　and　clicked　on　the　beam。　He　adjusted　several　dials　to　focus　the　beam。　In　a　moment；　the　image　came　into　focus；　green　and　black　on　the　screen。
　
　　　It　was　incredible。
　
　　　Jeremy　Stone　found　himself　staring　at　a　single　unit　of　the　organism。　It　was　a　perfect；　six…sided　hexagon；　and　it　interlocked　with　other　hexagons　on　each　side。　The　interior　of　the　hexagon　was　divided　into　wedges；　each　meeting　at　the　precise　center　of　the　structure。　The　overall　appearance　was　accurate；　with　a　kind　of　mathematical　precision　he　did　not　associate　with　life　on　earth。
　
　　　It　looked　like　a　crystal。
　
　　　He　smiled：　Leavitt　would　be　pleased。　Leavitt　liked　spectacular；　mind…stretching　things。　Leavitt　had　also　frequently　considered　the　possibility　that　life　might　be　based　upon　crystals　of　some　kind；　that　it　might　be　ordered　in　some　regular　pattern。
　
　　　He　decided　to　call　Leavitt　in。
　
　　　***
　
　　　＇graphic　of　EM　crystal　pattern＇　Caption：　（Early　sketch　by　Jeremy　Stone　of　hexagonal　Andromeda　configuration。　Photo　courtesy　Project　Wildfire。）
　
　　　As　soon　as　he　arrived；　Leavitt　said；　〃Well；　there's　our　answer。〃
　
　　　〃Answer　to　what？〃
　　　〃To　how　this　organism　functions。　I've　seen　the　results　of　spectrometry　and　amino…acid　analysis。〃
　　　〃And？〃
　　　〃The　organism　is　made　of　hydrogen；　carbon；　oxygen；　and　nitrogen。　But　it　has　no　amino　acids　at　all。　None。　Which　means　that　it　has　no　proteins　as　we　know　them；　and　no　enzymes。　I　was　wondering　how　it　could　survive　without　protein…based　organization。　Now　I　know。〃
　　　〃The　crystalline　structure。〃
　　　〃Looks　like　it；〃　Leavitt　said；　peering　at　the　screen。　〃In　three　dimensions；　it's　probably　a　hexagonal　slab；　like　a　piece　of　tile。　Eight…sided；　with　each　face　a　hexagon。　And　on　the　inside；　those　wedge…shaped　partments　leading　to　the　center。〃
　　　〃They　would　serve　to　separate　biochemical　functions　quite　well。〃　
　　　〃Yes；〃　Leavitt　said。　He　frowned。
　　　〃Something　the　matter？〃
　
　　　Leavitt　was　thinking；　remembering　something　he　had　forgotten。　A　dream；　about　a　house　and　a　city。　He　thought　for　a　moment　and　it　began　to　e　back　to　him。　A　house　and　a　city。　The　way　the　house　worked　alone；　and　the　way　it　worked　in　a　city。
　
　　　It　all　came　back。
　
　　　〃You　know；〃　he　said；　〃it's　interesting；　the　way　this　one　unit　interlocks　with　the　others　around　it。〃
　　　〃You're　wondering　if　we're　seeing　part　of　a　higher　organism？〃
　　　〃Exactly。　Is　this　unit　self…sufficient；　like　a　bacterium；　or　is　it　just　a　block　from　a　larger　organ；　or　a　larger　organism？　After　all；　if　you　saw　a　single　liver　cell；　could　you　guess　what　kind　of　an　organ　it　came　from？　No。　And　what　good　would　one　brain　cell　be　without　the　rest　of　the　brain？〃
　
　　　Stone　stared　at　the　screen　for　a　long　time。　〃A　rather　unusual　pair　of　analogies。　Because　the　liver　can　regenerate；　can　grow　back；　but　the　brain　cannot。〃　
　
　　　Leavitt　smiled。　〃The　Messenger　Theory。〃
　　　〃One　wonders；〃　Stone　said。
　
　　　The　Messenger　Theory　had　e　from　John　R。　Samuels；　a　munications　engineer。　Speaking　before　the　Fifth　Annual　Conference　on　Astronautics　and　munication；　he　had　reviewed　some　theories　about　the　way　in　which　an　alien　culture　might　choose　to　contact　other　cultures。　He　argued　that　the　most　advanced　concepts　in　munications　in　earth　technology　were　inadequate；　and　that　advanced　cultures　would　find　better　methods。
　
　　　〃Let　us　say　a　culture　wishes　to　scan　the　universe；〃　he　said。　〃Let　us　say　they　wish　to　have　a　sort　of　'ing…out　party'　on　a　galactic　scale　to　formally　announce　their　existence。　They　wish　to　spew　out　information；　clues　to　their　existence；　in　every　direction。　What　is　the　best　way　to　do　this？　Radio？　Hardly　radio　is　too　slow；　too　expensive；　and　it　decays　too　rapidly。　Strong　signals　weaken　within　a　few　billion　miles。　TV　is　even　worse。　Light　rays　are　fantastically