edge？
  What　lay　beyond　it？
  I　stretched　out　a　shaking　hand　and　touched　the　surface　of
  the　slab。　　A　faint　thrill　passed　through　my　hand　and　arm；
  oddly　unfamiliar　and　as　oddly　unpleasant；　as　of　electric　con…
  tact　holding　the　very　essence　of　cold。　　O'Keefe；　watching；
  imitated　my　action。　　As　his　fingers　rested　on　the　stone　his　face
  filled　with　astonishment。
  〃It's　the　door？〃　he　asked。　　I　nodded。　　There　was　a　low
  whistle　from　him　and　he　pointed　up　toward　the　top　of　the
  grey　stone。　　I　followed　the　gesture　and　saw；　above　the　moon
  door　and　on　each　side　of　it；　two　gently　curving　bosses　of
  rock；　perhaps　a　foot　in　diameter。
  〃The　moon　door's　keys；〃　I　said。
  〃It　begins　to　look　so；〃　answered　Larry。　　〃If　we　can　find
  them；〃　he　added。
  〃There's　nothing　we　can　do　till　moonrise；〃　I　replied。　　〃And
  we've　none　too　much　time　to　prepare　as　it　is。　　Come！〃
  A　little　later　we　were　beside　our　boat。　　We　lightered　it；
  set　up　the　tent；　and　as　it　was　now　but　a　short　hour　to　sun…
  down　I　bade　them　leave　me　and　make　their　search。　　They
  went　off　together；　and　I　busied　myself　with　opening　some　of
  the　paraphernalia　I　had　brought　with　me。
  First　of　all　I　took　out　the　two　Becquerel　ray…condensers
  that　I　had　bought　in　Sydney。　　Their　lenses　would　collect　and
  intensify　to　the　fullest　extent　any　light　directed　upon　them。
  I　had　found　them　most　useful　in　making　spectroscopic
  analysis　of　luminous　vapours；　and　I　knew　that　at　Yerkes　Ob…
  servatory　splendid　results　had　been　obtained　from　them　in
  collecting　the　diffused　radiance　of　the　nebulae　for　the　same
  purpose。
  If　my　theory　of　the　grey　slab's　mechanism　were　correct；
  it　was　practically　certain　that　with　the　satellite　only　a　few
  nights　past　the　full　we　could　concentrate　enough　light　on
  the　bosses　to　open　the　rock。　　And　as　the　ray　streams　through
  the　seven　globes　described　by　Throckmartin　would　be　too
  weak　to　energize　the　Pool；　we　could　enter　the　chamber　free
  from　any　fear　of　encountering　its　tenant；　make　our　prelimi…
  nary　observations　and　go　forth　before　the　moon　had　dropped
  so　far　that　the　concentration　in　the　condensers　would　fall
  below　that　necessary　to　keep　the　portal　from　closing。
  I　took　out　also　a　small　spectroscope；　and　a　few　other　in…
  struments　for　the　analysis　of　certain　light　manifestations　and
  the　testing　of　metal　and　liquid。　　Finally；　I　put　aside　my
  emergency　medical　kit。
  I　had　hardly　finished　examining　and　adjusting　these　be…
  fore　O'Keefe　and　Huldricksson　returned。　　They　reported
  signs　of　a　camp　at　least　ten　days　old　beside　the　northern
  wall　of　the　outer　court；　but　beyond　that　no　evidence　of　others
  beyond　ourselves　on　Nan…Tauach。
  We　prepared　supper；　ate　and　talked　a　little；　but　for　the
  most　part　were　silent。　　Even　Larry's　high　spirits　were　not　in
  evidence；　half　a　dozen　times　I　saw　him　take　out　his　auto…
  matic　and　look　it　over。　　He　was　more　thoughtful　than　I　had
  ever　seen　him。　　Once　he　went　into　the　tent；　rummaged　about
  a　bit　and　brought　out　another　revolver　which；　he　said；　he
  had　got　from　Da　Costa；　and　a　half…dozen　clips　of　cartridges。
  He　passed　the　gun　over　to　Olaf。
  At　last　a　glow　in　the　southeast　heralded　the　rising　moon。
  I　picked　up　my　instruments　and　the　medical　kit；　Larry　and
  Olaf　shouldered　each　a　short　ladder　that　was　part　of　my
  equipment；　and；　with　our　electric　flashes　pointing　the　way；
  walked　up　the　great　stairs；　through　the　enclosures；　and
  straight　to　the　grey　stone。
  By　this　time　the　moon　had　risen　and　its　clipped　light　shone
  full　upon　the　slab。　　I　saw　faint　gleams　pass　over　it　as　of　fleet…
  ing　phosphorescencebut　so　faint　were　they　that　I　could
  not　be　sure　of　the　truth　of　my　observation。
  We　set　the　ladders　in　place。　　Olaf　I　assigned　to　stand　be…
  fore　the　door　and　watch　for　the　first　signs　of　its　opening
  if　open　it　should。　　The　Becquerels　were　set　within　three…inch
  tripods；　whose　feet　I　had　equipped　with　vacuum　rings　to
  enable　them　to　hold　fast　to　the　rock。
  I　scaled　one　ladder　and　fastened　a　condenser　over　the　boss；
  descended；　sent　Larry　up　to　watch　it；　and；　ascending　the
  second　ladder；　rapidly　fixed　the　other　in　its　place。　　Then；　with
  O'Keefe　watchful　on　his　perch；　I　on　mine；　and　Olaf's　eyes
  fixed　upon　the　moon　door；　we　began　our　vigil。　　Suddenly
  there　was　an　exclamation　from　Larry。
  67
  MERRITT
  〃Seven　little　lights　are　beginning　to　glow　on　this　stone！〃
  he　cried。
  But　I　had　already　seen　those　beneath　my　lens　begin　to
  gleam　out　with　a　silvery　lustre。　　Swiftly　the　rays　within　the
  condenser　began　to　thicken　and　increase；　and　as　they　did　so
  the　seven　small　circles　waxed　like　stars　growing　out　of　the
  dusk；　and　with　a　queercurdled　is　the　best　word　I　can　find
  to　define　itradiance　entirely　strange　to　me。
  Beneath　me　I　heard　a　faint；　sighing　murmur　and　then　the
  voice　of　Huldricksson：
  〃It　opensthe　stone　turns〃
  I　began　to　climb　down　the　ladder。　　Again　came　Olaf's
  voice：
  〃The　stoneit　is　open〃　And　then　a　shriek；　a　wail　of
  blended　anguish　and　pity；　of　rage　and　despairand　the
  sound　of　swift　footsteps　racing　through　the　wall　beneath　me！
  I　dropped　to　the　ground。　　The　moon　door　was　wide　open；
  and　through　it　I　caught　a　glimpse　of　a　corridor　filled　with　a
  faint；　pearly　vaporous　light　like　earliest　misty　dawn。　　But　of
  Olaf　I　could　seenothing！　　And　even　as　I　stood；　gaping；　from
  behind　me　came　the　sharp　crack　of　a　rifle；　the　glass　of　the
  condenser　at　Larry's　side　flew　into　fragments；　he　dropped
  swiftly　to　the　ground；　the　automatic　in　his　hand　flashed　once；
  twice；　into　the　darkness。
  And　the　moon　door　began　to　pivot　slowly；　slowly　back
  into　its　place！
  I　rushed　toward　the　turning　stone　with　the　wild　idea　of
  holding　it　open。　　As　I　thrust　my　hands　against　it　there　came
  at　my　back　a　snarl　and　an　oath　and　Larry　staggered　under
  the　impact　of　a　body　that　had　flung　itself　straight　at　his
  throat。　　He　reeled　at　the　lip　of　the　shallow　cup　at　the　base
  of　the　slab；　slipped　upon　its　polished　curve；　fell　and　rolled
  with　that　which　had　attacked　him；　kicking　and　writhing；
  straight　through　the　narrowing　portal　into　the　passage！
  Forgetting　all　else；　I　sprang　to　his　aid。　　As　I　leaped　I　felt　the
  closing　edge　of　the　moon　door　graze　my　side。　　Then；　as　Larry
  raised　a　fist；　brought　it　down　upon　the　temple　of　the　man
  who　had　grappled　with　him　and　rose　from　the　twitching
  body　unsteadily　to　his　feet；　I　heard　shuddering　past　me　a
  mournful　whisper；　spun　about　as　though　some　giant's　hand
  had　whirled　me
  The　end　of　the　corridor　no　longer　opened　out　into　the
  moonlit　square　of　ruined　Nan…Tauach。　　It　was　barred　by　a
  solid　mass　of　glimmering　stone。　　The　moon　door　had　closed！
  O'Keefe　took　a　stumbling　step　toward　the　barrier　behind
  us。　There　was　no　mark　of　juncture　with　the　shining　walls；
  the　slab　fitted　into　the　sides　as　closely　as　a　mosaic。
  〃It's　shut　all　right；〃　said　Larry。　　〃But　if　there's　a　way　in；
  there's　a　way　out。　　Anyway；　Doc；　we're　right　in　the　pew　we've
  been　heading　forso　why　worry？〃　He　grinned　at　me　cheer…
  fully。　　The　man　on　the　floor　groaned；　and　he　dropped　to　his
  knees　beside　him。
  〃Marakinoff！〃　he　cried。
  At　my　exclamation　he　moved　aside；　turning　the　face　so　I
  could　see　it。　　It　was　clearly　Russian；　and　just　as　clearly　its
  possessor　was　one　of　unusual　force　and　intellect。
  The　strong；　massive　brow　with　orbital　ridge　unusually　de…
  veloped；　the　dominant；　high…bridged　nose；　the　straight　lips
  with　their　more　than　suggestion　of　latent　cruelty；　and　the
  strong　lines　of　the　jaw　beneath　a　black；　pointed　beard　all
  gave　evidence　that　here　was　a　personality　beyond　the　ordi…
  nary。
  〃Couldn't　be　anybody　else；〃　said　Larry；　breaking　in　on
  my　thoughts。　　〃He　must　have　been　watching　us　over　there
  from　Chau…ta…leur's　vault　all　the　time。〃
  Swiftly　he　ran　practised　hands　over　his　body；　then　stood
  erect；　holding　out　to　me　two　wicked…looking　magazine　pis…
  tols　and　a　knife。　　〃He　got　one　of　my　bullets　through　his　right
  forearm；　too；〃　he　said。　　〃Just　a　flesh　wound；　but　it　made　him
  drop　his　rifle。　　Some　arsenal；　our　little　Russian　scientist；
  what？〃
  I　opened　my　medical　kit。　　The　wound　was　a　slight　one；
  and　Larry　stood　looking　on　as　I　bandaged　it。
  〃Got　another　one　of　those　condensers？〃　he　asked；　sud…
  denly。　　〃And　do　you　suppose　Olaf　will　know　enough　to　use
  it？〃
  〃Larry；〃　I　answered；　〃Olaf's　not　outside！　　He's　in　here
  somewhere！〃
  His　jaw　dropped。
  〃The　hell　you　say！〃　he　whispered。
  〃Didn't　you　hear　him　shriek　when　the　stone　opened？〃　I
  asked。
  〃I　heard　him　yell；　yes；〃　he　said。　　〃But　I　didn't　know　what
  was　the　matter。　　And　then　this　wildcat　jumped　me〃　　He
  paused　and　his　eyes　widened。　　〃Which　way　did　he　go？〃　he
  asked　swiftly。　　I　pointed　down　the　faintly　glowing　passage。
  〃There's　only　one　way；〃　I　said。
  〃Watch　that　bird　close；〃　hissed　O'Keefe；　pointing　to　Mara…
  kinoffand　pistol　in　hand　stretched　his　long　legs　and　raced
  away。　　I　look