may　they　hold　that　some　projectile　might　have　been　shot　through　the
  partly　opened　window　and　none　of　us　have　detected　the　act。〃
  〃Ah；　yes；〃　rejoined　Maitland；　〃but　when　I　ask　them　where　this
  implement　is　under　this　assumption；　and　remind　them　of　what　I　shall
  already　have　told　them；　viz。；　that　Mr。　Darrow　sat　back　to　the　window
  as　well　as　over　eight　feet　from　it；　and　sat　in　a　chair；　the　solid
  back　of　which　extended；　like　a　protecting　shield；　fully　six　inches
  above　the　top　of　his　head；　they　will　find　it　difficult　to　show　how；
  unless　projectiles　travel　in　sharp　curves　or　angles；　a　man　in　this
  position　could　thus　receive　a　wound　directly　beneath　his　chin；　a
  wound　so　slight　as　not　to　penetrate　the　thyroid　cartilage　immediately
  under　it。
  〃The　abandonment　of　this　hypothesis　will　force　them　to　relinquish
  the　idea　that　the　murder　was　committed　from　without。　　What　then
  remains？　　Only　the　second　alternative。　　They　must　either　give　up
  altogether　the　idea　of　murder；　or　have　recourse　to　what　is　known　as
  the　theory　of　exclusive　opportunity。〃
  〃Theory　of　exclusive　opportunity；〃　repeated　Gwen；　as　a　puzzled　look
  overspread　her　countenance。　　〃I　…　I　fear　I　do　not　quite　understand
  what　you　mean。〃
  〃Pardon　me；　Miss　Darrow；　for　not　making　my　meaning　clearer　to　you；〃
  said　Maitland　with　a　deferential　inclination　of　the　head。　　〃The
  theory　of　exclusive　opportunity；　to　state　it　plainly　in　this　case；
  means　simply　this：　if　Mr。　Darrow　were　murdered；　some　one　of　us　five；
  we　being　the　only　ones　having　an　opportunity　to　do　the　deed；　must
  be　the　assassin。　　Whether　this　view　be　taken；　or　that　of　suicide；　it
  becomes　of　paramount　importance　to　find　the　weapon。　　Do　you　not　now
  see　why　I　objected　to　having　anyone　leave　the　room？　　If；　as　appears
  likely　from　my　search；　the　weapon　is　not　to　be　found；　and　if；　as　I
  feel　reasonably　certain；　either　the　suicide　or　the　murder　theory　be
  substantiated；　then；　anyone　who　left　the　room　before　official　search
  was　made　would　be　held　to　have　taken　the　weapon　with　him　and　disposed
  of　it；　because　his　would　have　been　the　exclusive　opportunity　of　so
  doing。　　Someone　must　have　disposed　of　it；　and　no　one　else　had　a
  chance　to　do　so；　that　would　be　the　way　it　would　be　stated。　　But；
  since　no　one　of　us　has　left　the　room；　a　thorough　search　both　of　it
  and　of　our　persons；　must　convince　the　officers　that　we；　at　least；
  are　not　responsible　for　the　fact　that　the　weapon　is　not　forthcoming。〃
  Maitland　paused　and　looked　at　Browne　as　if　he　expected　him　to　speak；
  but　that　gentleman　only　shut　his　square　jaws　the　more　firmly　together
  and　held　his　peace；　…　at　least　in　so　far　as　words　were　concerned。
  If　looks；　like　actions；　〃speak　louder　than　words；〃　this　black　visage
  with　its　two　points　of　fire　made　eloquent　discourse。　　I　charged　all
  this　display　of　malice　to　jealousy。　　It　is　not　altogether　pleasant
  to　be　placed　at　a　disadvantage　before　the　one　being　whose　good
  opinion　one　prizes　above　all　things　else；　…　that　is　to　say；　I　have
  read　that　such　is　the　case。　　I　do　not　consider　my　own　views　upon
  such　matters　expert　testimony。　　In　all　affairs　of　the　heart　my
  opinions　cease　to　have　weight　at　exactly　the　point　where　that　organ
  ceases　to　be　a　pump。
  Even　Gwen；　I　think；　noticed　Browne's　determined　silence；　for　she
  said　to　Maitland：
  〃I　am　very　grateful　that　your　forethought　prevented　me　from　causing
  Mr。　Browne　even　temporary　annoyance　by　making　him　my　messenger。〃
  She　paused　a　moment　and　then　continued：
  〃You　were　speaking　of　the　officers'　theories。　　When　they　have
  convinced　themselves　that　no　one　of　us　has　removed　the　weapon；　what
  then？〃
  〃In　my　opinion；〃　said　Maitland；　〃they　will　ultimately　fall　back　upon
  the　suicide　theory；　but　they　must　find　the　weapon　here　before　they
  can　substantiate　it；　for　if　it　be　not　here　someone　must　have　taken
  it　away　and　that　someone　could　have　only　been　the　one　who　used　it
  …　the　assassin；　in　short　…　but　here　are　the　officers。　　Let　each　one
  of　us　insist　upon　being　searched。　　They　can　send　to　the　station　for
  a　woman　to　search　you；〃　he　said　in　an　undertone　to　Gwen　and　then
  added：　〃I　trust　you　will　pardon　my　suggesting　a　course　which；　in
  your　case；　seems　so　utterly　unnecessary；　but；　believe　me；　there　are
  urgent　reasons　for　it　which　I　can　explain　later。　　If　we　would　hope
  to　solve　this　mystery；　everything　depends　upon　absolute　thoroughness
  at　this　juncture。〃
  〃I　should　evince　but　poor　appreciation；〃　Gwen　replied；　〃of　the
  ability　you　have　already　shown　should　I　fail　to　follow　your　slightest
  suggestion。　　It　is　all　I　can　offer　you　by　way　of　thanks　for　the
  kind　interest　you　have　taken。〃
  The　return　of　Officer　Barker；　accompanied　by　three　other　men；　now
  changed　the　tide　of　conversation。　　Maitland　advanced　and　shook　hands
  with　one　whom　he　introduced　as　Mr。　Osborne；　and　this　gentleman　in
  turn　introduced　his　brother　officer；　a　Mr。　Allen；　and　；　a
  special　detective。
  Osborne　impressed　me　as　a　man　of　only　mediocre　ability；　thoroughly
  imbued　with　the　idea　that　he　is　exceptionally　clever。　　He　spoke
  loudly　and；　I　thought；　a　bit　ostentatiously；　yet　withal　in　a　manner
  so　frank　and　hearty　that　I　could　not　help　liking　the　fellow。
  ；　on　the　contrary；　seemed　retiring　almost　to　the　point　of
  self…abnegation。　　He　said　but　little；　apparently　preferring　to　keep
  in　the　background；　where　he　could　record　his　own　observations　in
  his　note…book　without　too　frequent　interruption。　　His　manner　was
  polished　in　the　extreme；　and　so　frank　withal　that　he　seemed　to　me
  like　a　man　of　glass　through　whom　every　thought　shone　unhindered。
  I　wondered　how　one　who　seemed　powerless　to　conceal　his　own　emotions
  should　possess　a　detective's　ability　to　thread　his　way　through　the
  dark　and　hidden　duplicity　of　crime。　　When　he　spoke　it　was　in　a　low；
  velvety；　and　soothing　voice；　that　fell　upon　the　ear　with　an
  irresistible　charm。　　When　Osborne　would　make　some　thoughtless
  remark　fraught　with　bitterness　for　Gwen；　such　an　expression　of　pain
  would　flit　across　's　fine　face　as　one　occasionally　sees
  in　those　highly　organised　and　sympathetic　natures；　　…　usually　found
  among　women　if　a　doctor's　experience　may　be　trusted；　…　which　catch
  the　throb　of　another's　hurt；　even　as　adjacent　strings　strive　to
  sing　each　other's　songs。
  seemed　to　me　more　priest　than　detective。　　His　clean…shaven
  face；　its　beautifully　chiselled　features　suffused　with　that　peculiar
  pallor　which　borrows　the　transparency　of　marble；　the　large；　limpid
  brown　eyes　and　the　delicate；　kindly　mouth　…　all　these；　combined　with
  a　faultless　manner　and　a　carriage　suggestive　of　power　in　reserve；
  so　fascinated　me　that　I　found　myself　watching　him　continually。　　I
  remember　saying　to　myself：　〃What　a　rival　he　would　make　in　a　woman's
  affections！〃
  At　just　that　time　he　was　looking　at　Gwen　with　tender；　solicitous
  sympathy　written　in　every　feature；　and　that　doubtless　suggested　my
  thought。
  Mr。　Allen　was　even　more　ordinary　than　Mr。　Osborne　in　manner　and
  appearance。　　I　do　not　presume　to　judge　his　real　merits；　for　I　did
  not　notice　him　sufficiently　to　properly　portray　him　to　you；　even
  if　I　had　the　gift　of　description；　which　I　think　you　will　admit　I
  have　not。　　He　lives　in　my　memory　only　as　a　something　tall；　spare；
  coarse　of　texture；　red；　hairy；　and　redolent　of　poor　tobacco。
  How　different　men　are！　　（Of　course　women　are　all　alike！）　While
  Osborne；　like　a　good…natured　bumble…bee；　was　buzzing　noisily　about；
  as　though　all　the　world　were　his　clover…blossom；　and　Allen；　so　far
  as　I　know；　was　doing　nothing；　；　alert　and　keen　despite　his
  gentleness　and　a　modesty　which　kept　him　for　the　most　part
  unobtrusively　in　the　shadow　of　his　chosen　corner；　was　writing
  rapidly　in　a　note…book　and　speaking　no　word。　　It　seemed　as　if
  nothing　escaped　him。　　　Clearly　he　was　there　to　enlighten　himself
  rather　than　others。　　At　length；　pausing　to　make　a　measurement；
  he　noticed　my　gaze　and　said　to　me　in　an　undertone；　as　he　glanced
  solicitously　at　Gwen　lest　she　should　hear：
  〃Pardon　me；　but　did　any　of　you　observe　anything；　at　or　about　the
  time　of　Mr。　Darrow's　death；　which　impressed　you　as　singular；　…　any
  noise；　any　shadow；　any　draught　or　change　of　temperature；　say　a
  rushing　or　I　might　say　swishing　sound；　…　anything；　in　fact；　that
  would　seem　to　you　as　at　all　unusual？〃
  〃Nothing　whatever；〃　I　replied。　　〃Everything　seemed　perfectly　normal
  and　commonplace。〃
  〃Hum！　　Strange！〃　he　said；　and　returned　to　his　notes。
  I　felt　sure　　had　had　a　theory　and　that　my　testimony　had　not
  strengthened　it；　but　he　did　not　volunteer　any　information；　neither
  did　he　take　part　in　the　conversation　of　his　companions；　and　so　my
  curiosity　remained　ungratified。　　It　was　clear　that　's　methods
  were　very　different　from　those　of　Osborne　and　Allen。
  I　need　not　weary　you　by　further　narrating　what　occurred　at　this
  official　examination。　　Suffice　it　to　say　that；　with　one　or　two　minor
  exceptions；　Osborne　and　Allen　followed　the　precise　course　of
  reasoning　prophesied　by　Maitland；　and；　as　for　；　he
  courteously；　but　firmly；　held　his　peace。　　The　two　officers　did　not；
  however；　lean　as　strongly　to　the　theory　that　death　resulted　from
  natural　causes　as　Maitland　had　anticipated；　and；　I　think；　this
  surprised
  him。　　He　had　already　told　them　that　he　expected　to　be　able　to　show
  death　to　have　resulted　from　poison　hyp