It　seemed；　indeed；　that　we　now　had　a　thread　by　means　of　which　we
  should　be　able　to　follow　up　this　extraordinary　mystery。
  〃Then　it　is　almost　certain；〃　said　Monsieur　Stangerson；　〃that　my
  daughter　did　lose　the　key；　and　that　she　did　not　tell　me　of　it；
  wishing　to　spare　any　anxiety；　and　that　she　begged　whoever　had　found
  it　to　write　to　the　poste　restante。　　She　evidently　feared　that；　by
  giving　our　address；　inquiries　would　have　resulted　that　would　have
  apprised　me　of　the　loss　of　the　key。　　It　was　quite　logical；　quite
  natural　for　her　to　have　taken　that　course　…　for　I　have　been　robbed
  once　before。〃
  〃Where　was　that；　and　when？〃　asked　the　Chief　of　the　Surete。
  〃Oh！　　many　years　ago；　in　America；　in　Philadelphia。　　There　were
  stolen　from　my　laboratory　the　drawings　of　two　inventions　that　might
  have　made　the　fortune　of　a　man。　　Not　ouly　have　I　never　learnt　who
  the　thief　was；　but　I　have　never　heard　even　a　word　of　the　object　of
  the　robbery；　doubtless　because；　in　order　to　defeat　the　plans　of　the
  person　who　had　robbed　me；　I　myself　brought　these　two　inventions
  before　the　public；　and　so　rendered　the　robbery　of　no　avail。　　From
  that　time　on　I　have　been　very　careful　to　shut　myself　in　when　I　am
  at　work。　　The　bars　to　these　windows；　the　lonely　situation　of　this
  pavilion；　this　cabinet；　which　I　had　specially　constructed；　this
  special　lock；　this　unique　key；　all　are　precautions　against　fears
  inspired　by　a　sad　experience。〃
  〃Most　interesting！〃　remarked　Monsieur　Dax。
  Monsieur　Rouletabille　asked　about　the　reticule。　　Neither　Monsieur
  Stangerson　nor　Daddy　Jacques　had　seen　it　for　several　days；　but　a　few
  hours　later　we　learned　from　Mademoiselle　Stangerson　herself　that　the
  reticule　had　either　been　stolen　from　her；　or　she　had　lost　it。　　She
  further　corroborated　all　that　had　passed　just　as　her　father　had
  stated。　　She　had　gone　to　the　poste　restante　and；　on　the　23rd　of
  October；　had　received　a　letter　which；　she　affirmed；　contained　nothing
  but　a　vulgar　pleasantry；　which　she　had　immediately　burned。
  To　return　to　our　examination；　or　rather　to　our　conversation。　　I　must
  state　that　the　Chief　of　the　Surete　having　inquired　of　Monsieur
  Stangerson　under　what　conditions　his　daughter　had　gone　to　Paris　on
  the　20th　of　October；　we　learned　that　Monsieur　Robert　Darzac　had
  accompanied　her；　and　Darzac　had　not　been　again　seen　at　the　chateau
  from　that　time　to　the　day　after　the　crime　had　been　committed。　　The
  fact　that　Monsieur　Darzac　was　with　her　in　the　Grands　Magasins　de　la
  Louvre　when　the　reticule　disappeared　could　not　pass　unnoticed；　and；
  it　must　be　said；　strongly　awakened　our　interest。
  This　conversation　between　magistrates；　accused；　victim；　witnesses
  and　journalist；　was　coming　to　a　close　when　quite　a　theatrical
  sensation　…　an　incident　of　a　kind　displeasing　to　Monsieur　de
  Marquet　…　was　produced。　　The　officer　of　the　gendarmes　came　to
  announce　that　Frederic　Larsan　requested　to　be　admitted；　…　a　request
  that　was　at　once　complied　with。　　He　held　in　his　hand　a　heavy　pair
  of　muddy　boots；　which　he　threw　on　the　pavement　of　the　laboratory。
  〃Here；〃　he　said；　〃are　the　boots　worn　by　the　murderer。　　Do　you
  recognise　them；　Daddy　Jacques？〃
  Daddy　Jacques　bent　over　them　and；　stupefied；　recognised　a　pair　of
  old　boots　which　he　had；　some　time　back；　thrown　into　a　corner　of　his
  attic。　　He　was　so　taken　aback　that　he　could　not　hide　his　agitation。
  Then　pointing　to　the　handkerchief　in　the　old　man's　hand；　Frederic
  Larsan　said：
  〃That's　a　handkerchief　astonishingly　like　the　one　found　in　The
  Yellow　Room。〃
  〃I　know；〃　said　Daddy　Jacques；　trembling；　〃they　are　almost　alike。〃
  〃And　then；〃　continued　Frederic　Larsan；　〃the　old　Basque　cap　also
  found　in　The　Yellow　Room　might　at　one　time　have　been　worn　by　Daddy
  Jacques　himself。　　All　this；　gentlemen；　proves；　I　think；　that　the
  murderer　wished　to　disguise　his　real　personality。　　He　did　it　in　a
  very　clumsy　way　…　or；　at　least；　so　it　appears　to　us。　　Don't　be
  alarmed；　Daddy　Jacques；　we　are　quite　sure　that　you　were　not　the
  murderer；　you　never　left　the　side　of　Monsieur　Stangerson。　　But　if
  Monsieur　Stangerson　had　not　been　working　that　night　and　had　gone
  back　to　the　chateau　after　parting　with　his　daughter；　and　Daddy
  Jacques　had　gone　to　sleep　in　his　attic；　no　one　would　have　doubted
  that　he　was　the　murderer。　　He　owes　his　safety；　therefore；　to　the
  tragedy　having　been　enacted　too　soon；　…　the　murderer；　no　doubt；
  from　the　silence　in　the　laboratory；　imagined　that　it　was　empty；　and
  that　the　moment　for　action　had　come。　　The　man　who　had　been　able　to
  introduce　himself　here　so　mysteriously　and　to　leave　so　many　evidences
  against　Daddy　Jacques；　was；　there　can　be　no　doubt；　familiar　with　the
  house。　　At　what　hour　exactly　he　entered；　whether　in　the　afternoon　or
  in　the　evening；　I　cannot　say。　　One　familiar　with　the　proceedings　and
  persons　of　this　pavilion　could　choose　his　own　time　for　entering　The
  Yellow　Room。〃
  〃He　could　not　have　entered　it　if　anybody　had　been　in　the　laboratory；〃
  said　Monsieur　de　Marquet。
  〃How　do　we　know　that？〃　replied　Larsan。　　〃There　was　the　dinner　in
  the　laboratory；　the　coming　and　going　of　the　servants　in　attendance。
  There　was　a　chemical　experiment　being　carried　on　between　ten　and
  eleven　o'clock；　with　Monsieur　Stangerson；　his　daughter；　and　Daddy
  Jacques　engaged　at　the　furnace　in　a　corner　of　the　high　chimney。
  Who　can　say　that　the　murderer　…　an　intimate！　　…　a　friend！　　…　did
  not　take　advantage　of　that　moment　to　slip　into　The　Yellow　Room；
  after　having　taken　off　his　boots　in　the　lavatory？〃
  〃It　is　very　improbable；〃　said　Monsieur　Stangerson。
  〃Doubtless　…　but　it　is　not　impossible。　　I　assert　nothing。　　As　to
  the　escape　from　the　pavilion　…　that's　another　thing；　the　most
  natural　thing　in　the　world。〃
  For　a　moment　Frederic　Larsan　paused；　…　a　moment　that　appeared　to
  us　a　very　long　time。　　The　eagerness　with　which　we　awaited　what　he
  was　going　to　tell　us　may　be　imagined。
  〃I　have　not　been　in　The　Yellow　Room；〃　he　continued；　〃but　I　take　it
  for　granted　that　you　have　satisfied　yourselves　that　he　could　have
  left　the　room　only　by　way　of　the　door；　it　is　by　the　door；　then；　that
  the　murderer　made　his　way　out。　　At　what　time？　　At　the　moment　when　it
  was　most　easy　for　him　to　do　so；　at　the　moment　when　it　became　most
  explainable　…　so　completely　explainable　that　there　can　be　no　other
  explanation。　　Let　us　go　over　the　moments　which　followed　after　the
  crime　had　been　committed。　　There　was　the　first　moment；　when　Monsieur
  Stangerson　and　Daddy　Jacques　were　close　to　the　door；　ready　to　bar
  the　way。　　There　was　the　second　moment；　during　which　Daddy　Jacques
  was　absent　and　Monsieur　Stangerson　was　left　alone　before　the　door。
  There　was　a　third　moment；　when　Monsieur　Stangerson　was　joined　by
  the　concierge。　　There　was　a　fourth　moment；　during　which　Monsieur
  Stangerson；　the　concierge　and　his　wife　and　Daddy　Jacques　were　before
  the　door。　　There　was　a　fifth　moment；　during　which　the　door　was　burst
  open　and　The　Yellow　Room　entered。　　The　moment　at　which　the　flight　is
  explainable　is　the　very　moment　when　there　was　the　least　number　of
  persons　before　the　door。　　There　was　one　moment　when　there　was　but
  one　person；　…　Monsieur　Stangerson。　　Unless　a　complicity　of　silence
  on　the　part　of　Daddy　Jacques　is　admitted　…　in　which　I　do　not　believe
  …　the　door　was　opened　in　the　presence　of　Monsieur　Stangerson　alone
  and　the　man　escaped。
  〃Here　we　must　admit　that　Monsieur　Stangerson　had　powerful　reasons
  for　not　arresting；　or　not　causing　the　arrest　of　the　murderer；　since
  he　allowed　him　to　reach　the　window　in　the　vestibule　and　closed　it
  after　him！　…　That　done；　Mademoiselle　Stangerson；　though　horribly
  wounded；　had　still　strength　enough；　and　no　doubt　in　obedience　to　the
  entreaties　of　her　father；　to　refasten　the　door　of　her　chamber；　with
  both　the　bolt　and　the　lock；　before　sinking　on　the　floor。　　We　do　not
  know　who　committed　the　crime；　we　do　not　know　of　what　wretch　Monsieur
  and　Mademoiselle　Stangerson　are　the　victims；　but　there　is　no　doubt
  that　they　both　know！　　The　secret　must　be　a　terrible　one；　for　the
  father　had　not　hesitated　to　leave　his　daughter　to　die　behind　a　door
  which　she　had　shut　upon　herself；　…　terrible　for　him　to　have　allowed
  the　assassin　to　escape。　　For　there　is　no　other　way　in　the　world　to
  explain　the　murderer's　flight　from　The　Yellow　Room！〃
  The　silence　which　followed　this　dramatic　and　lucid　explanation　was
  appalling。　　We　all　of　us　felt　grieved　for　the　illustrious　professor；
  driven　into　a　corner　by　the　pitiless　logic　of　Frederic　Larsan；　forced
  to　confess　the　whole　truth　of　his　martyrdom　or　to　keep　silent；　and
  thus　make　a　yet　more　terrible　admission。　　The　man　himself；　a
  veritable　statue　of　sorrow；　raised　his　hand　with　a　gesture　so　solemn
  that　we　bowed　our　heads　to　it　as　before　something　sacred。　　He　then
  pronounced　these　words；　in　a　voice　so　loud　that　it　seemed　to　exhaust
  him：
  〃I　swear　by　the　head　of　my　suffering　child　that　I　never　for　an
  instant　left　the　door　of　her　chamber　after　hearing　her　cries　for
  help；　that　that　door　was　not　opened　while　I　was　alone　in　the
  laboratory；　and　that；　finally；　when　we　entered　The　Yellow　Room；　my
  three　domestics　and　I；　the　murderer　was　no　longer　there！　　I　swear
  I　do　not　know　the　murderer！〃
  Must　I　say　it；　…　in　spite　of　the　solemnity　of　Monsieur　Stangerson's
  words；　we　did　not　bel