Stangerson　herself　if；　as　I　thought；　she　had　taken　refuge　in　the
  boudoir　for　the　purpose　of　avoiding　the　murderer　who　was　coming
  to　see　her。　　In　any　case；　he　must　return　to　the　gallery　where　my
  people　were　awaiting　him　at　every　possible　exit。
  〃On　coming　there；　he　would　see　on　his　left；　Monsieur　Stangerson；　he
  would　turn　to　the　right；　towards　the　'off…turning'　gallery　…　the　way
  he　had　pre…arranged　for　flight；　where；　at　the　intersection　of　the
  two　galleries；　he　would　see　at　once；　as　I　have　explained；　on　his
  left；　Frederic　Larsan　at　the　end　of　the　'off…turning'　gallery；　and
  in　front；　Daddy　Jacques；　at　the　end　of　the　'right'　gallery。　　Monsieur
  Stangerson　and　myself　would　arrive　by　way　of　the　back　of　the　chateau。
  …　He　is　ours！　　…　He　can　no　longer　escape　us！　　I　was　sure　of　that。
  〃The　plan　I　had　formed　seemed　to　me　the　best；　the　surest；　and　the
  most　simple。　　It　would；　no　doubt；　have　been　simpler　still；　if　we
  had　been　able　to　place　some　one　directly　behind　the　door　of
  Mademoiselle's　boudoir；　which　opened　out　of　her　bedchamber；　and；
  in　that　way；　had　been　in　a　position　to　besiege　the　two　doors　of　the
  room　in　which　the　man　was。　　But　we　could　not　penetrate　the　boudoir
  except　by　way　of　the　drawing…room；　the　door　of　which　had　been
  locked　on　the　inside　by　Mademoiselle　Stangerson。　　But　even　if　I　had
  had　the　free　disposition　of　the　boudoir；　I　should　have　held　to　the
  plan　I　had　formed；　because　any　other　plan　of　attack　would　have
  separated　us　at　the　moment　of　the　struggle　with　the　man；　while　my
  plan　united　us　all　for　the　attack；　at　a　spot　which　I　had　selected
  with　almost　mathematical　precision；　…　the　intersection　of　the　two
  galleries。
  〃Having　so　placed　my　people；　I　again　left　the　chateau；　hurried　to
  my　ladder；　and；　replacing　it；　climbed　up；　revolver　in　hand。
  〃If　there　be　any　inclined　to　smile　at　my　taking　so　many　precautionary
  measures；　I　refer　them　to　the　mystery　of　The　Yellow　Room；　and　to　all
  the　proofs　we　have　of　the　weird　cunning　of　the　murderer。　　Further；　if
  there　be　some　who　think　my　observations　needlessly　minute　at　a　moment
  when　they　ought　to　be　completely　held　by　rapidity　of　movement　and
  decision　of　action；　I　reply　that　I　have　wished　to　report　here；　at
  length　and　completely；　all　the　details　of　a　plan　of　attack　conceived
  so　rapidly　that　it　is　only　the　slowness　of　my　pen　that　gives　an
  appearance　of　slowness　to　the　execution。　　I　have　wished；　by　this
  slowness　and　precision；　to　be　certain　that　nothing　should　be　omitted
  from　the　conditions　under　which　the　strange　phenomenon　was　produced；
  which；　until　some　natural　explanation　of　it　is　forthcoming；　seems　to
  me　to　prove；　even　better　than　the　theories　of　Professor　Stangerson；
  the　Dissociation　of　Matter　…　I　will　even　say；　the　instantaneous
  Dissociation　of　Matter。〃
  Chapter　XVI
  Strange　Phenomenon　of　the　Dissociation　of　Matter
  （EXTRACT　FROM　THE　NOTE…BOOK　OF　JOSEPH　ROULETABILLE；　continued）
  〃I　am　again　at　the　window…sill；〃　continues　Rouletabille；　〃and　once
  more　I　raise　my　head　above　it。　　Through　an　opening　in　the　curtains；
  the　arrangement　of　which　has　not　been　changed；　I　am　ready　to　look；
  anxious　to　note　the　position　in　which　I　am　going　to　find　the　murderer；
  …　whether　his　back　will　still　be　turned　towards　me！　　…　whether　he　is
  still　seated　at　the　desk　writing！　　But　perhaps　…　perhaps　…　he　is　no
  longer　there！　…　Yet　how　could　he　have　fled？　…　Was　I　not　in　possession
  of　his　ladder？　　I　force　myself　to　be　cool。　　I　raise　my　head　yet
  higher。　　I　look　…　he　is　still　there。　　I　see　his　monstrous　back；
  deformed　by　the　shadow　thrown　by　the　candle。　　He　is　no　longer
  writing　now；　and　the　candle　is　on　the　parquet；　over　which　he　is
  bending　…　a　position　which　serves　my　purpose。
  〃I　hold　my　breath。　　I　mount　the　ladder。　　I　am　on　the　uppermost　rung
  of　it；　and　with　my　left　hand　seize　hold　of　the　window…sill。　　In　this
  moment　of　approaching　success；　I　feel　my　heart　beating　wildly。　　I
  put　my　revolver　between　my　teeth。　　A　quick　spring；　and　I　shall　be
  on　the　window…ledge。　　But　…　the　ladder！　　I　had　been　obliged　to　press
  on　it　heavily；　and　my　foot　had　scarcely　left　it；　when　I　felt　it
  swaying　beneath　me。　　It　grated　on　the　wall　and　fell。　　But；　already；
  my　knees　were　touching　the　window…sill；　and；　by　a　movement　quick　as
  lightning；　I　got　on　to　it。
  〃But　the　murderer　had　been　even　quicker　than　I　had　been。　　He　had
  heard　the　grating　of　the　ladder　on　the　wall；　and　I　saw　the　monstrous
  back　of　the　man　raise　itself。　　I　saw　his　head。　　Did　I　really　see　it？
  …　The　candle　on　the　parquet　lit　up　his　legs　only。　　Above　the　height
  of　the　table　the　chamber　was　in　darkness。　　I　saw　a　man　with　long
  hair；　a　full　beard；　wild…looking　eyes；　a　pale　face；　framed　in　large
  whiskers；　…　as　well　as　I　could　distinguish；　and；　as　I　think　…　red
  in　colour。　　I　did　not　know　the　face。　　That　was；　in　brief；　the　chief
  sensation　I　received　from　that　face　in　the　dim　half…light　in　which　I
  saw　it。　　I　did　not　know　it　…　or；　at　least；　I　did　not　recognise　it。
  〃Now　for　quick　action！　　It　was　indeed　time　for　that；　for　as　I　was
  about　to　place　my　legs　through　the　window；　the　man　had　seen　me；　had
  bounded　to　his　feet；　had　sprung　…　as　I　foresaw　he　would　…　to　the
  door　of　the　ante…chamber；　had　time　to　open　it；　and　fled。　　But　I　was
  already　behind　him；　revolver　in　hand；　shouting　'Help！'
  〃Like　an　arrow　I　crossed　the　room；　but　noticed　a　letter　on　the　table
  as　I　rushed。　　I　almost　came　up　with　the　man　in　the　ante…room；　for　he
  had　lost　time　in　opening　the　door　to　the　gallery。　　I　flew　on　wings；
  and　in　the　gallery　was　but　a　few　feet　behind　him。　　He　had　taken；　as
  I　supposed　he　would；　the　gallery　on　his　right；　…　that　is　to　say；　the
  road　he　had　prepared　for　his　flight。　　'Help；　Jacques！　…　help；　Larsan！'
  I　cried。　　He　could　not　escape　us！　　I　raised　a　shout　of　joy；　of
  savage　victory。　　The　man　reached　the　intersection　of　the　two
  galleries　hardly　two　seconds　before　me　for　the　meeting　which　I　had
  prepared　…　the　fatal　shock　which　must　inevitably　take　place　at　that
  spot！　　We　all　rushed　to　the　crossing…place　…　Monsieur　Stangerson
  and　I　coming　from　one　end　of　the　right　gallery；　Daddy　Jacques　coming
  from　the　other　end　of　the　same　gallery；　and　Frederic　Larsan　coming
  from　the　'off…turning'　gallery。
  〃The　man　was　not　there！
  〃We　looked　at　each　other　stupidly　and　with　eyes　terrified。　　The　man
  had　vanished　like　a　ghost。　　'Where　is　he　…　where　is　he？'　we　all
  asked。
  'It　is　impossible　he　can　have　escaped！'　I　cried；　my　terror　mastered
  by　my　anger。
  〃'I　touched　him！'　exclaimed　Frederic　Larsan。
  〃'I　felt　his　breath　on　my　face！'　cried　Daddy　Jacques。
  〃'Where　is　he？'　…　where　is　he？'　we　all　cried。
  〃We　raced　like　madmen　along　the　two　galleries；　we　visited　doors　and
  windows　…　they　were　closed；　hermetically　closed。　　They　had　not　been
  opened。　　Besides；　the　opening　of　a　door　or　window　by　this　man　whom
  we　were　hunting；　without　our　having　perceived　it；　would　have　been
  more　inexplicable　than　his　disappearance。
  〃Where　is　he？　　…　where　is　he？　　…　He　could　not　have　got　away　by　a
  door　or　a　window；　nor　by　any　other　way。　　He　could　not　have　passed
  through　our　bodies！
  〃I　confess　that；　for　the　moment；　I　felt　'done　for。'　For　the　gallery
  was　perfectly　lighted；　and　there　was　neither　trap；　nor　secret　door
  in　the　walls；　nor　any　sort　of　hiding…place。　　We　moved　the　chairs　and
  lifted　the　pictures。　　Nothing！　…　nothing！　　We　would　have　looked　into
  a　flower…pot；　if　there　had　been　one　to　look　into！〃
  When　this　mystery；　thanks　to　Rouletabille；　was　naturally　explained；
  by　the　help　alone　of　his　masterful　mind；　we　were　able　to　realise
  that　the　murderer　had　got　away　neither　by　a　door；　a　window；　nor　the
  stairs　？a　fact　which　the　judges　would　not　admit。
  CHAPTER　XVII
  The　Inexplicable　Gallery
  〃Mademoiselle　Stangerson　appeared　at　the　door　of　her　ante…room；〃
  continues　Rouletabille's　note…book。　　〃We　were　near　her　door　in　the
  gallery　where　this　incredible　phenomenon　had　taken　place。　　There
  are　moments　when　one　feels　as　if　one's　brain　were　about　to　burst。
  A　bullet　in　the　head；　a　fracture　of　the　skull；　the　seat　of　reason
  shattered　？with　only　these　can　I　compare　the　sensation　which
  exhausted　and　left　me　void　of　sense。
  〃Happily；　Mademoiselle　Stangerson　appeared　on　the　threshold　of　her
  ante…room。　　I　saw　her；　and　that　helped　to　relieve　my　chaotic　state
  of　mind。　I　breathed　her　？I　inhaled　the　perfume　of　the　lady　in　black；
  whom　I　should　never　see　again。　　I　would　have　given　ten　years　of　my
  life　？half　my　life　？to　see　once　more　the　lady　in　black！　　Alas！
  I　no　more　meet　her　but　from　time　to　time；　？and　yet！　　？and　yet！
  how　the　memory　of　that　perfume　？felt　by　me　alone　？carries　me　back
  to　the　days　of　my　childhood。*　　It　was　this　sharp　reminder　from　my
  beloved　perfume；　of　the　lady　in　black；　which　made　me　go　to　her
  ？dressed　wholly　in　white　and　so　pale　？so　pale　and　so　beautiful！
  ？on　the　threshold　of　the　inexplicable　gallery。　　Her　beautiful
  golden　hair；　gathered　into　a　knot　on　the　back　of　her　neck；　left
  visible　the　red　star　on　her　temple　which　had　so　nearly　been　the
  cause　of　her　death。　　When　I　first　got　on　the　right　track　of　the
  mystery　of　this　case　I　had　imagined　that；　on　the　night　of　the
  tragedy　in　The　Yellow　Room；　Mademoiselle　Stangerson　had　worn　her
  hair　in　bands。　　But　then；　how　could　　I　have　imagined　othe