snow。　But　right　up　against　these　dreary　colours　rose　the　black　bulk　of　the　cathedral；　and　upon　the　top　of　the　cathedral　was　a　random　splash　and　great　stain　of　snow；　still　clinging　as　to　an　Alpine　peak。　It　had　fallen　accidentally；　but　just　so　fallen　as　to　half　drape　the　dome　from　its　very　topmost　point；　and　to　pick　out　in　perfect　silver　the　great　orb　and　the　cross。　When　Syme　saw　it　he　suddenly　straightened　himself；　and　made　with　his　sword…stick　an　involuntary　salute。
  He　knew　that　that　evil　figure；　his　shadow；　was　creeping　quickly　or　slowly　behind　him；　and　he　did　not　care。
  It　seemed　a　symbol　of　human　faith　and　valour　that　while　the　skies　were　darkening　that　high　place　of　the　earth　was　bright。　The　devils　might　have　captured　heaven；　but　they　had　not　yet　captured　the　cross。　He　had　a　new　impulse　to　tear　out　the　secret　of　this　dancing；　jumping　and　pursuing　paralytic；　and　at　the　entrance　of　the　court　as　it　opened　upon　the　Circus　he　turned；　stick　in　hand；　to　face　his　pursuer。
  Professor　de　Worms　came　slowly　round　the　corner　of　the　irregular　alley　behind　him；　his　unnatural　form　outlined　against　a　lonely　gas…lamp；　irresistibly　recalling　that　very　imaginative　figure　in　the　nursery　rhymes；　〃the　crooked　man　who　went　a　crooked　mile。〃　He　really　looked　as　if　he　had　been　twisted　out　of　shape　by　the　tortuous　streets　he　had　been　threading。　He　came　nearer　and　nearer；　the　lamplight　shining　on　his　lifted　spectacles；　his　lifted；　patient　face。　Syme　waited　for　him　as　St。　George　waited　for　the　dragon；　as　a　man　waits　for　a　final　explanation　or　for　death。　And　the　old　Professor　came　right　up　to　him　and　passed　him　like　a　total　stranger；　without　even　a　blink　of　his　mournful　eyelids。
  There　was　something　in　this　silent　and　unexpected　innocence　that　left　Syme　in　a　final　fury。　The　man's　colourless　face　and　manner　seemed　to　assert　that　the　whole　following　had　been　an　accident。　Syme　was　galvanised　with　an　energy　that　was　something　between　bitterness　and　a　burst　of　boyish　derision。　He　made　a　wild　gesture　as　if　to　knock　the　old　man's　hat　off；　called　out　something　like　〃Catch　me　if　you　can；〃　and　went　racing　away　across　the　white；　open　Circus。　Concealment　was　impossible　now；　and　looking　back　over　his　shoulder；　he　could　see　the　black　figure　of　the　old　gentleman　coming　after　him　with　long；　swinging　strides　like　a　man　winning　a　mile　race。　But　the　head　upon　that　bounding　body　was　still　pale；　grave　and　professional；　like　the　head　of　a　lecturer　upon　the　body　of　a　harlequin。
  This　outrageous　chase　sped　across　Ludgate　Circus；　up　Ludgate　Hill；　round　St。　Paul's　Cathedral；　along　Cheapside；　Syme　remembering　all　the　nightmares　he　had　ever　known。　Then　Syme　broke　away　towards　the　river；　and　ended　almost　down　by　the　docks。　He　saw　the　yellow　panes　of　a　low；　lighted　public…house；　flung　himself　into　it　and　ordered　beer。　It　was　a　foul　tavern；　sprinkled　with　foreign　sailors；　a　place　where　opium　might　be　smoked　or　knives　drawn。
  A　moment　later　Professor　de　Worms　entered　the　place；　sat　down　carefully；　and　asked　for　a　glass　of　milk。
  CHAPTER　VIII
  THE　PROFESSOR　EXPLAINS
  WHEN　Gabriel　Syme　found　himself　finally　established　in　a　chair；　and　opposite　to　him；　fixed　and　final　also；　the　lifted　eyebrows　and　leaden　eyelids　of　the　Professor；　his　fears　fully　returned。　This　incomprehensible　man　from　the　fierce　council；　after　all；　had　certainly　pursued　him。　If　the　man　had　one　character　as　a　paralytic　and　another　character　as　a　pursuer；　the　antithesis　might　make　him　more　interesting；　but　scarcely　more　soothing。　It　would　be　a　very　small　comfort　that　he　could　not　find　the　Professor　out；　if　by　some　serious　accident　the　Professor　should　find　him　out。　He　emptied　a　whole　pewter　pot　of　ale　before　the　professor　had　touched　his　milk。
  One　possibility；　however；　kept　him　hopeful　and　yet　helpless。　It　was　just　possible　that　this　escapade　signified　something　other　than　even　a　slight　suspicion　of　him。　Perhaps　it　was　some　regular　form　or　sign。　Perhaps　the　foolish　scamper　was　some　sort　of　friendly　signal　that　he　ought　to　have　understood。　Perhaps　it　was　a　ritual。　Perhaps　the　new　Thursday　was　always　chased　along　Cheapside；　as　the　new　Lord　Mayor　is　always　escorted　along　it。　He　was　just　selecting　a　tentative　inquiry；　when　the　old　Professor　opposite　suddenly　and　simply　cut　him　short。　Before　Syme　could　ask　the　first　diplomatic　question；　the　old　anarchist　had　asked　suddenly；　without　any　sort　of　preparation
  〃Are　you　a　policeman？〃
  Whatever　else　Syme　had　expected；　he　had　never　expected　anything　so　brutal　and　actual　as　this。　Even　his　great　presence　of　mind　could　only　manage　a　reply　with　an　air　of　rather　blundering　jocularity。
  〃A　policeman？〃　he　said；　laughing　vaguely。　〃Whatever　made　you　think　of　a　policeman　in　connection　with　me？〃
  〃The　process　was　simple　enough；〃　answered　the　Professor　patiently。　〃I　thought　you　looked　like　a　policeman。　I　think　so　now。〃
  〃Did　I　take　a　policeman's　hat　by　mistake　out　of　the　restaurant？〃　asked　Syme；　smiling　wildly。　〃Have　I　by　any　chance　got　a　number　stuck　on　to　me　somewhere？　Have　my　boots　got　that　watchful　look？　Why　must　I　be　a　policeman？　Do；　do　let　me　be　a　postman。〃
  The　old　Professor　shook　his　head　with　a　gravity　that　gave　no　hope；　but　Syme　ran　on　with　a　feverish　irony。
  〃But　perhaps　I　misunderstood　the　delicacies　of　your　German　philosophy。　Perhaps　policeman　is　a　relative　term。　In　an　evolutionary　sense；　sir；　the　ape　fades　so　gradually　into　the　policeman；　that　I　myself　can　never　detect　the　shade。　The　monkey　is　only　the　policeman　that　may　be。　Perhaps　a　maiden　lady　on　Clapham　Common　is　only　the　policeman　that　might　have　been。　I　don't　mind　being　the　policeman　that　might　have　been。　I　don't　mind　being　anything　in　German　thought。〃
  〃Are　you　in　the　police　service？〃　said　the　old　man；　ignoring　all　Syme's　improvised　and　desperate　raillery。　〃Are　you　a　detective？〃
  Syme's　heart　turned　to　stone；　but　his　face　never　changed。
  〃Your　suggestion　is　ridiculous；〃　he　began。　〃Why　on　earth〃
  The　old　man　struck　his　palsied　hand　passionately　on　the　rickety　table；　nearly　breaking　it。
  〃Did　you　hear　me　ask　a　plain　question；　you　pattering　spy？〃　he　shrieked　in　a　high；　crazy　voice。　〃Are　you；　or　are　you　not；　a　police　detective？〃
  〃No！〃　answered　Syme；　like　a　man　standing　on　the　hangman's　drop。
  〃You　swear　it；〃　said　the　old　man；　leaning　across　to　him；　his　dead　face　becoming　as　it　were　loathsomely　alive。　〃You　swear　it！　You　swear　it！　If　you　swear　falsely；　will　you　be　damned？　Will　you　be　sure　that　the　devil　dances　at　your　funeral？　Will　you　see　that　the　nightmare　sits　on　your　grave？　Will　there　really　be　no　mistake？　You　are　an　anarchist；　you　are　a　dynamiter！　Above　all；　you　are　not　in　any　sense　a　detective？　You　are　not　in　the　British　police？〃
  He　leant　his　angular　elbow　far　across　the　table；　and　put　up　his　large　loose　hand　like　a　flap　to　his　ear。
  〃I　am　not　in　the　British　police；〃　said　Syme　with　insane　calm。
  Professor　de　Worms　fell　back　in　his　chair　with　a　curious　air　of　kindly　collapse。
  〃That's　a　pity；〃　he　said；　〃because　I　am。〃
  Syme　sprang　up　straight；　sending　back　the　bench　behind　him　with　a　crash。
  〃Because　you　are　what？〃　he　said　thickly。　〃You　are　what？〃
  〃I　am　a　policeman；〃　said　the　Professor　with　his　first　broad　smile。　and　beaming　through　his　spectacles。　〃But　as　you　think　policeman　only　a　relative　term；　of　course　I　have　nothing　to　do　with　you。　I　am　in　the　British　police　force；　but　as　you　tell　me　you　are　not　in　the　British　police　force；　I　can　only　say　that　I　met　you　in　a　dynamiters'　club。　I　suppose　I　ought　to　arrest　you。〃　And　with　these　words　he　laid　on　the　table　before　Syme　an　exact　facsimile　of　the　blue　card　which　Syme　had　in　his　own　waistcoat　pocket；　the　symbol　of　his　power　from　the　police。
  Syme　had　for　a　flash　the　sensation　that　the　cosmos　had　turned　exactly　upside　down；　that　all　trees　were　growing　downwards　and　that　all　stars　were　under　his　feet。　Then　came　slowly　the　opposite　conviction。　For　the　last　twenty…four　hours　the　cosmos　had　really　been　upside　down；　but　now　the　capsized　universe　had　come　right　side　up　again。　This　devil　from　whom　he　had　been　fleeing　all　day　was　only　an　elder　brother　of　his　own　house；　who　on　the　other　side　of　the　table　lay　back　and　laughed　at　him。　He　did　not　for　the　moment　ask　any　questions　of　detail；　he　only　knew　the　happy　and　silly　fact　that　this　shadow；　which　had　pursued　him　with　an　intolerable　oppression　of　peril；　was　only　the　shadow　of　a　friend　trying　to　catch　him　up。　He　knew　simultaneously　that　he　was　a　fool　and　a　free　man。　For　with　any　recovery　from　morbidity　there　must　go　a　certain　healthy　humiliation。　There　comes　a　certain　point　in　such　conditions　when　only　three　things　are　possible：　first　a　perpetuation　of　Satanic　pride；　secondly　tears；　and　third　laughter。　Syme's　egotism　held　hard　to　the　first　course　for　a　few　seconds；　and　then　suddenly　adopted　the　third。　Taking　his　own　blue　police　ticket　from　his　own　waist　coat　pocket；　he　tossed　it　on　to　the　table；　then　he　flung　his　head　back　until　his　spike　of　yellow　beard　almost　pointed　at　the　ceiling；　and　shouted　with　a　barbaric　laughter。
  Even　in　that　close　den；　perpetually　filled　with　the　din　of　knives；　plates；　cans；　clamorous　voices；　sudden　struggles　and　stampedes；　there　was　something　Homeric　in　Syme's　mirth　which　made　many　half…drunken　men　look　round。
  〃What　yer　laughing　at；　guv'nor？〃　aske