well　as　locked。　We　would　do　better　in　the　area。　There　is　an
  excellent　archway　down　yonder　in　case　a　too　zealous　policeman　should
  intrude。　Give　me　a　hand；　Watson；　and　I'll　do　the　same　for　you。〃
  A　minute　later　we　were　both　in　the　area。　Hardly　had　we　reached　the
  dark　shadows　before　the　step　of　the　policeman　was　heard　in　the　fog
  above。　As　its　soft　rhythm　died　away；　Holmes　set　to　work　upon　the　lower
  door。　I　saw　him　stoop　and　strain　until　with　a　sharp　crash　it　flew
  open。　We　sprang　through　into　the　dark　passage；　closing　the　area　door
  behind　us。　Holmes　led　the　way　up　the　curving；　uncarpeted　stair。　His
  little　fan　of　yellow　light　shone　upon　a　low　window。
  〃Here　we　are；　Watson…　this　must　be　the　one。〃　He　threw　it　open；　and
  as　he　did　so　there　was　a　low；　harsh　murmur；　growing　steadily　into　a
  loud　roar　as　a　train　dashed　past　us　in　the　darkness。　Holmes　swept
  his　light　along　the　window…sill。　It　was　thickly　coated　with　soot
  from　the　passing　engines；　but　the　black　surface　was　blurred　and　rubbed
  in　places。
  〃You　can　see　where　they　rested　the　body。　Halloa；　Watson！　what　is
  this？　There　can　be　no　doubt　that　it　is　a　blood　mark。〃　He　was
  pointing　to　faint　discolourations　along　the　woodwork　of　the　window。
  〃Here　it　is　on　the　stone　of　the　stair　also。　The　demonstration　is
  complete。　Let　us　stay　here　until　a　train　stops。〃
  We　had　not　long　to　wait。　The　very　next　train　roared　from　the
  tunnel　as　before；　but　slowed　in　the　open；　and　then；　with　a　creaking　of
  brakes；　pulled　up　immediately　beneath　us。　It　was　not　four　feet　from
  the　window…ledge　to　the　roof　of　the　carriages。　Holmes　softly　closed
  the　window。
  〃So　far　we　are　justified；〃　said　he。　〃What　do　you　think　of　it；
  Watson？〃
  〃A　masterpiece。　You　have　never　risen　to　a　greater　height。〃
  〃I　cannot　agree　with　you　there。　From　the　moment　that　I　conceived　the
  idea　of　the　body　being　upon　the　roof；　which　surely　was　not　a　very
  abstruse　one；　all　the　rest　was　inevitable。　If　it　were　not　for　the
  grave　interests　involved　the　affair　up　to　this　point　would　be
  insignificant。　Our　difficulties　are　still　before　us。　But　perhaps　we
  may　find　something　here　which　may　help　us。〃
  We　had　ascended　the　kitchen　stair　and　entered　the　suite　of　rooms
  upon　the　first　floor。　One　was　a　dining…room；　severely　furnished　and
  containing　nothing　of　interest。　A　second　was　a　bedroom；　which　also
  drew　blank。　The　remaining　room　appeared　more　promising　and　my
  companion　settled　down　to　a　systematic　examination。　It　was　littered
  with　books　and　papers；　and　was　evidently　used　as　a　study。　Swiftly
  and　methodically　Holmes　turned　over　the　contents　of　drawer　after
  drawer　and　cupboard　after　cupboard；　but　no　gleam　of　success　came　to
  brighten　his　austere　face。　At　the　end　of　an　hour　he　was　no　further
  than　when　he　started。
  〃The　cunning　dog　has　covered　his　tracks；〃　said　he。　〃He　has　left
  nothing　to　incriminate　him。　His　dangerous　correspondence　has　been
  destroyed　or　removed。　This　is　our　last　chance。〃
  It　was　a　small　tin　cash…box　which　stood　upon　the　writing…desk。
  Holmes　pried　it　open　with　his　chisel。　Several　rolls　of　paper　were
  within；　covered　with　figures　and　calculations；　without　any　note　to
  show　to　what　they　referred。　The　recurring　words；　'water　pressure'
  and　'pressure　to　the　square　inch'　suggested　some　possible　relation
  to　a　submarine。　Holmes　tossed　them　all　impatiently　aside。　There　only
  remained　an　envelope　with　some　small　newspaper　slips　inside　it。　He
  shook　them　out　on　the　table；　and　at　once　I　saw　by　his　eager　face
  that　his　hopes　had　been　raised。
  〃What's　this；　Watson？　Eh？　What's　this？　Record　of　a　series　of
  messages　in　the　advertisements　of　a　paper。　Daily　Telegraph　agony
  column　by　the　print　and　paper。　Right…hand　top　corner　of　a　page。　No
  dates…　but　messages　arrange　themselves。　This　must　be　the　first：
  〃Hoped　to　hear　sooner。　Terms　agreed　to。　Write　fully　to　address　given
  on　card。　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　　〃PIERROT。
  〃Next　comes：
  〃Too　complex　for　description。　Must　have　full　report。　Stuff　awaits
  you　when　goods　delivered。　　　　　　　　　　　　　　　　　　　　　〃PIERROT。
  〃Then　comes：
  〃Matter　presses。　Must　withdraw　offer　unless　contract　completed。　Make
  appointment　by　letter。　Will　confirm　by　advertisement。
  〃PIERROT。
  〃Finally：
  〃Monday　night　after　nine。　Two　taps。　Only　ourselves。　Do　not　be　so
  suspicious。　Payment　in　hard　cash　when　goods　delivered。
  〃PIERROT。
  〃A　fairly　complete　record；　Watson！　If　we　could　only　get　at　the　man
  at　the　other　end！〃　He　sat　lost　in　thought；　tapping　his　fingers　on
  the　table。　Finally　he　sprang　to　his　feet。
  〃Well；　perhaps　it　won't　be　so　difficult；　after　all。　There　is　nothing
  more　to　be　done　here；　Watson。　I　think　we　might　drive　round　to　the
  offices　of　the　Daily　Telegraph；　and　so　bring　a　good　day's　work　to　a
  conclusion。〃
  Mycroft　Holmes　and　Lestrade　had　come　round　by　appointment　after
  breakfast　next　day　and　Sherlock　Holmes　had　recounted　to　them　our
  proceedings　of　the　day　before。　The　professional　shook　his　head　over
  our　confessed　burglary。
  〃We　can't　do　these　things　in　the　force；　Mr。　Holmes；〃　said　he。　〃No
  wonder　you　get　results　that　are　beyond　us。　But　some　of　these　days
  you'll　go　too　far；　and　you'll　find　yourself　and　your　friend　in
  trouble。〃
  〃For　England；　home　and　beauty…　eh；　Watson？　Martyrs　on　the　altar　of
  our　country。　But　what　do　you　think　of　it；　Mycroft？〃
  〃Excellent；　Sherlock！　Admirable！　But　what　use　will　you　make　of　it？〃
  Holmes　picked　up　the　Daily　Telegraph　which　lay　upon　the　table。
  〃Have　you　seen　Pierrot's　advertisement　to…day？〃
  〃What？　Another　one？〃
  〃Yes；　here　it　is：
  〃To…night。　Same　hour。　Same　place。　Two　taps。　Most　vitally
  important。　Your　own　safety　at　stake。
  〃PIERROT。
  〃By　George！〃　cried　Lestrade。　〃If　he　answers　that　we've　got　him！〃
  〃That　was　my　idea　when　I　put　it　in。　I　think　if　you　could　both　make
  it　convenient　to　come　with　us　about　eight　o'clock　to　Caulfield　Gardens
  we　might　possibly　get　a　little　nearer　to　a　solution。〃
  One　of　the　most　remarkable　characteristics　of　Sherlock　Holmes　was
  his　power　of　throwing　his　brain　out　of　action　and　switching　all　his
  thoughts　on　to　lighter　things　whenever　he　had　convinced　himself　that
  he　could　no　longer　work　to　advantage。　I　remember　that　during　the　whole
  of　that　memorable　day　he　lost　himself　in　a　monograph　which　he　had
  undertaken　upon　the　Polyphonic　Motets　of　Lassus。　For　my　own　part　I　had
  none　of　this　power　of　detachment；　and　the　day；　in　consequence；
  appeared　to　be　interminable。　The　great　national　importance　of　the
  issue；　the　suspense　in　high　quarters；　the　direct　nature　of　the
  experiment　which　we　were　trying…　all　combined　to　work　upon　my　nerve。
  It　was　a　relief　to　me　when　at　last；　after　a　light　dinner；　we　set　out
  upon　our　expedition。　Lestrade　and　Mycroft　met　us　by　appointment　at　the
  outside　of　Gloucester　Road　Station。　The　area　door　of　Oberstein's　house
  had　been　left　open　the　night　before；　and　it　was　necessary　for　me；　as
  Mycroft　Holmes　absolutely　and　indignantly　declined　to　climb　the
  railings；　to　pass　in　and　open　the　hall　door。　By　nine　o'clock　we　were
  all　seated　in　the　study；　waiting　patiently　for　our　man。
  An　hour　passed　and　yet　another。　When　eleven　struck；　the　measured
  beat　of　the　great　church　clock　seemed　to　sound　the　dirge　of　our　hopes。
  Lestrade　and　Mycroft　were　fidgeting　in　their　seats　and　looking　twice　a
  minute　at　their　watches。　Holmes　sat　silent　and　composed；　his　eyelids
  half　shut；　but　every　sense　on　the　alert。　He　raised　his　head　with　a
  sudden　jerk。
  〃He　is　coming；〃　said　he。
  There　had　been　a　furtive　step　past　the　door。　Now　it　returned。　We
  heard　a　shuffling　sound　outside；　and　then　two　sharp　taps　with　the
  knocker。　Holmes　rose；　motioning　to　us　to　remain　seated。　The　gas　in　the
  hall　was　a　mere　point　of　light。　He　opened　the　outer　door；　and　then
  as　a　dark　figure　slipped　past　him　he　closed　and　fastened　it。　〃This
  way！〃　we　heard　him　say；　and　a　moment　later　our　man　stood　before　us。
  Holmes　had　followed　him　closely；　and　as　the　man　turned　with　a　cry　of
  surprise　and　alarm　he　caught　him　by　the　collar　and　threw　him　back　into
  the　room。　Before　our　prisoner　had　recovered　his　balance　the　door　was
  shut　and　Holmes　standing　with　his　back　against　it。　The　man　glared
  round　him；　staggered；　and　fell　senseless　upon　the　floor。　With　the
  shock；　his　broad…brimmed　hat　flew　from　his　head；　his　cravat　slipped
  down　from　his　lips；　and　there　were　the　long　light　beard　and　the
  soft；　handsome　delicate　features　of　Colonel　Valentine　Walter。
  Holmes　gave　a　whistle　of　surprise。
  〃You　can　write　me　down　an　ass　this　time；　Watson；〃　said　he。　〃This　was
  not　the　bird　that　I　was　looking　for。〃
  〃Who　is　he？〃　asked　Mycroft　eagerly。
  〃The　younger　brother　of　the　late　Sir　James　Walter；　the　head　of　the
  Submarine　Department。　Yes；　yes；　I　see　the　fall　of　the　cards。　He　is
  coming　to。　I　think　that　you　had　best　leave　his　examination　to　me。〃
  We　had　carried　the　prostrate　body　to　the　sofa。　Now　our　prisoner
  sat　up；　looked　round　him　with　a　horror…stricken　face；　and　passed　his
  hand　over　his　f