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手机浏览器扫描二维码访问

第27部分（第2页）

＇＇180＇＇　〃I　never　thought　about　it　until　we　started　to　get　spiral　messages。　Harry　says　its　because　the　thing…the　famous　it…believes　we　think　in　spirals。　But　its　just　as　likely　that　it　thinks　in　spirals　and　so　it　assumes　we　do；　too。　The　sphere　is　round；　isnt　it？　And　weve　been　seeing　all　these　radially　symmetrical　animals。　Jellyfish；　squid。〃

〃Nice　idea；〃　Beth　said；　〃except　for　the　fact　that　squid　arent　radially　symmetrical。　An　octopus　is。　And；　like　an　octopus；　squid　have　a　round　circle　of　tentacles；　but　squidre　bilaterally　symmetrical；　with　a　matching　left　and　right　side；　the　way　we　have。　And　then　theres　the　shrimps。〃

〃Thats　right；　the　shrimps。〃　Norman　had　forgotten　about　the　shrimps。

〃I　cant　see　a　connection　between　the　sphere　and　the　animals；〃　Beth　said。

They　heard　the　thumping　again；　soft；　rhythmic。　Sitting　in　his　chair；　Norman　realized　that　he　could　feel　the　thumping　as　well；　as　a　slight　impact。　〃What　is　that；　anyway？〃

〃I　dont　know。　Sounds　like　its　ing　from　outside。〃

He　had　started　toward　the　porthole　when　the　inter　clicked　and　he　heard　Barnes　say；　〃Now　hear　this；　all　hands　to　munications。　All　hands　to　munications。　Dr。　Adams　has　broken　the　code。〃

Harry　wouldnt　tell　them　the　message　right　away。　Relishing　his　triumph；　he　insisted　on　going　through　the　decoding　process；　step　by　step。　First；　he　explained；　he　had　thought　that　the　messages　might　express　some　universal　constant；　or　some　physical　law；　stated　as　a　way　to　open　conversation。　〃But；〃　Harry　said；　〃it　might　also　be　a　graphic　representation　of　some　kind…code　for　a　picture…which　presented　immense　problems。　After　all；　whats　a　picture？　We　make　pictures　on　a　flat　plane；　like　a　piece　of　paper。　We　determine　positions　within　a　picture　by　what　we　call　X　and　Y　axes。　Vertical　and　horizontal。　But　another　intelligence　might　see　images　and　organize　them　very　differently。　It　might　assume　more　than　three　dimensions。　Or　it　might　work　from　the　center　of　the　picture　outward；　for　example。　So　the　code　＇＇181＇＇　might　be　very　tough。　I　didnt　make　much　progress　at　first。〃　Later；　when　he　got　the　same　message　with　gaps　between　number　sequences；　Harry　began　to　suspect　that　the　code　represented　discrete　chunks　of　information…suggesting　words；　not　pictures。　〃Now；　word　codes　fall　into　several　types；　from　simple　to　plex。　There　was　no　way　to　know　immediately　which　method　of　encoding　had　been　used。　But　then　I　had　a　sudden　insight。〃

They　waited；　impatiently；　for　his　insight。

〃Why　use　a　code　at　all？〃　Harry　asked。

〃Why　use　a　code？〃　Norman　said。

〃Sure。　If　you　are　trying　to　municate　with　someone；　you　dont　use　a　code。　Codes　are　ways　of　hiding　munication。　So　perhaps　this　intelligence　thinks　he　is　municating　directly；　but　is　actually　making　some　kind　of　logical　mistake　in　talking　to　us。　He　is　making　a　code　without　ever　intending　to　do　so。　That　suggested　the　unintentional　code　was　probably　a　substitution　code；　with　numbers　for　letters。　When　I　got　the　word　breaks；　I　began　to　try　and　match　numbers　to　letters　by　frequency　analysis。　In　frequency　analysis　you　break　down　codes　by　using　the　fact　that　the　most　mon　letter　in　English　is　e；　and　the　second　most　mon　letter　is　t；　and　so　on。　So　I　looked　for　the　most　mon　numbers。　But　I　was　impeded　by　the　fact　that　even　a　short　number　sequence；　such　as　two…three…two；　might　represent　many　code　possibilities：　two　and　three　and　two；　twenty…three　and　two；　two　and　thirtytwo；　or　two　hundred　and　thirty…two。　Longer　code　sequences　had　many　more　possibilities。〃

Then；　he　said；　he　was　sitting　in　front　of　the　puter　thinking　about　the　spiral　messages；　and　he　suddenly　looked　at　the　keyboard。　〃I　began　to　wonder　what　an　alien　intelligence　would　make　of　our　keyboard；　those　rows　of　symbols　on　a　device　made　to　be　pressed。　How　confusing　it　must　look　to　another　kind　of　creature！　Look　here；〃　he　said。　〃The　letters　on　a　regular　keyboard　go　like　this。〃　He　held　up　his　＇＇182＇＇　pad。

1234567890

tab　　QWERTYUIOP

capsASDFGHJKL；

shiftZXCVBNM；。？

〃And　then　I　imagined　what　the　keyboard　would　look　like　as　a　spiral；　since　our　creature　seems　to　prefer　spirals。　And　I　started　numbering　the　keys　in　concentric　circles。

〃It　took　a　little　experimentation；　since　the　keys　dont　line　up　exactly；　but　finally　I　got　it；〃　he　said。　〃Look　here：　the　numbers　spiral　out　from　the　center。　G　is　one；　B　is　two；　H　is　three；　Y　is　four；　and　so　on。　See？　Its　like　this。〃　He　quickly　penciled　in　numbers。

12345612711990

tabQWER13T5Y4U101OP

capsASD14F6G1H3J9KL；

shiftZXC15V7B2N8M；。？

〃They　just　keep　spiraling　outward…M　is　sixteen；　K　is　seventeen；　and　so　forth。　So　finally　I　understood　the　message。〃

〃What　is　the　message；　Harry？〃

Harry　hesitated。　〃I　have　to　tell　you。　Its　strange。〃

〃How　do　you　mean；　strange？〃

Harry　tore　another　sheet　off　his　yellow　pad　and　handed　it　to　them。　Norman　read　the　short　message；　printed　in　neat　block　letters：