titude　crept　a　suggestion　of　grudging　respect；　Olaf；　tremb…
  ling；　watched　silently。
  〃Dr。　　Goodwin　and　my　impetuous　young　friend；　you；〃
  went　on　Marakinoff　after　a　moment's　silence　and　I　won…
  dered　vaguely　why　he　did　not　include　Huldricksson　in　his
  address〃it　is　time　that　we　have　an　understanding。　　I　have
  a　proposal　to　make　to　you　also。　　It　is　this；　we　are　what　you
  call　a　bad　boat；　and　all　of　us　are　in　it。　　Da！　　We　need　all
  hands；　is　it　not　so？　　Let　us　put　together　our　knowledge　and
  our　brains　and　resourcesand　even　a　poonch　of　a　mule　is　a
  resource；〃　he　looked　wickedly　at　O'Keefe；　〃and　pull　our
  boat　into　quiet　waters　again。　　After　that〃
  〃All　very　well；　Marakinoff；〃　interjected　Larry；　〃but　I　don't
  feel　very　safe　in　any　boat　with　somebody　capable　of　shoot…
  ing　me　through　the　back。〃
  Marakinoff　waved　a　deprecatory　hand。
  〃It　was　natural　that；〃　he　said；　〃logical；　da！　　Here　is　a　very
  great　secret；　perhaps　many　secrets　to　my　country　invalua…
  ble〃　He　paused；　shaken　by　some　overpowering　emotion；
  the　veins　in　his　forehead　grew　congested；　the　cold　eyes
  blazed　and　the　guttural　voice　harshened。
  〃I　do　not　apologize　and　I　do　not　explain；〃　rasped　Mara…
  kinoff。　　〃But　I　will　tell　you；　da！　　Here　is　my　country　sweating
  blood　in　an　experiment　to　liberate　the　world。　　And　here　are
  the　other　nations　ringing　us　like　wolves　and　waiting　to
  spring　at　our　throats　at　the　least　sign　of　weakness。　　And　here
  are　you；　Lieutenant　O'Keefe　of　the　English　wolves；　and　you
  Dr。　Goodwin　of　the　Yankee　packand　here　in　this　place
  may　be　that　will　enable　my　country　to　win　its　war　for　the
  worker。　　What　are　the　lives　of　you　two　and　this　sailor　to　that？
  Less　than　the　flies　I　crush　with　my　hand；　less　than　midges
  in　the　sunbeam！〃
  He　suddenly　gripped　himself。
  〃But　that　is　not　now　the　important　thing；〃　he　resumed；
  almost　coldly。　　〃Not　that　nor　my　shooting。　　Let　us　squarely　the
  situation　face。　　My　proposal　is　so：　that　we　join　interests；　and
  what　you　call　see　it　through　together；　find　our　way　through
  this　place　and　those　secrets　learn　of　which　I　have　spoken；
  if　we　can。　　And　when　that　is　done　we　will　go　our　ways；　to　his
  own　land　each；　to　make　use　of　them　for　our　lands　as　each　of
  us　may。　　On　my　part；　I　offer　my　knowledgeand　it　is　very
  valuable；　Dr。　Goodwinand　my　training。　　You　and　Lieu…
  tenant　O'Keefe　do　the　same；　and　this　man　Olaf；　what　he
  can　of　his　strength；　for　I　do　not　think　his　usefulness　lies　in
  his　brains；　no。〃
  〃In　effect；　Goodwin；〃　broke　in　Larry　as　I　hesitated；　〃the
  professor's　proposition　is　this：　he　wants　to　know　what's　go…
  ing　on　here　but　he　begins　to　realize　it's　no　one　man's　job
  and　besides　we　have　the　drop　on　him。　　We're　three　to　his　one；
  and　we　have　all　his　hardware　and　cutlery。　　But　also　we　can
  do　better　with　him　than　without　himjust　as　he　can　do
  better　with　us　than　without　us。　　It's　an　even　breakfor　a
  while。　　But　once　he　gets　that　information　he's　looking　for；
  then　look　out。　　You　and　Olaf　and　I　are　the　wolves　and　the
  flies　and　the　midges　againand　the　strafing　will　be　about
  due。　　Nevertheless；　with　three　to　one　against　him；　if　he　can
  get　away　with　it　he　deserves　to。　　I'm　for　taking　him　up；　if　you
  are。〃
  There　was　almost　a　twinkle　in　Marakinoff's　eyes。
  〃It　is　not　just　as　I　would　have　put　it；　perhaps；〃　he　said；
  〃but　in　its　skeleton　he　has　right。　　Nor　will　I　turn　my　hand
  against　you　while　we　are　still　in　danger　here。　　I　pledge　you
  my　honor　on　this。〃
  Larry　laughed。
  〃All　right；　Professor；〃　he　grinned。　　〃I　believe　you　mean
  every　word　you　say。　　Nevertheless；　I'll　just　keep　the　guns。〃
  Marakinoff　bowed；　imperturbably。
  〃And　now；〃　he　said；　〃I　will　tell　you　what　I　know。　　I　found
  the　secret　of　the　door　mechanism　even　as　you　did；　Dr。　Good…
  win。　　But　by　carelessness；　my　condensers　were　broken。　　I　was
  forced　to　wait　while　I　sent　for　othersand　the　waiting　might
  be　for　months。　　I　took　certain　precautions；　and　on　the　first
  night　of　this　full　moon　I　hid　myself　within　the　vault　of
  Chau…ta…leur。〃
  An　involuntary　thrill　of　admiration　for　the　man　went
  through　me　at　the　manifest　heroism　of　this　leap　in　the　dark。
  I　could　see　it　reflected　in　Larry's　face。
  〃I　hid　in　the　vault；〃　continued　Marakinoff；　〃and　I　saw
  that　which　comes　from　here　come　out。　　I　waitedlong　hours。
  At　last；　when　the　moon　was　low；　it　returnedecstatically
  with　a　man；　a　native；　in　embrace　enfolded。　　It　passed　through
  the　door；　and　soon　then　the　moon　became　low　and　the　door
  closed。
  〃The　next　night　more　confidence　was　mine；　yes。　　And　after
  that　which　comes　had　gone；　I　looked　through　its　open　door。
  I　said；　〃It　will　not　return　for　three　hours。　　While　it　is　away；
  why　shall　I　not　into　its　home　go　through　the　door　it　has　left
  open？'　So　I　wenteven　to　here。　　I　looked　at　the　pillars　of
  light　and　I　tested　the　liquid　of　the　Pool　on　which　they　fell。
  That　liquid；　Dr。　Goodwin；　is　not　water；　and　it　is　not　any
  fluid　known　on　earth。〃　He　handed　me　a　small　vial；　its　neck
  held　in　a　long　thong。
  〃Take　this；〃　he　said；　〃and　see。〃
  Wonderingly；　I　took　the　bottle；　dipped　it　down　into　the
  Pool。　　The　liquid　was　extraordinarily　light；　seemed；　in　fact；
  to　give　the　vial　buoyancy。　　I　held　it　to　the　light。　　It　was　striated；
  streaked；　as　though　little　living；　pulsing　veins　ran　through　it。
  And　its　blueness；　even　in　the　vial；　held　an　intensity　of　lumi…
  nousness。
  〃Radioactive；〃　said　Marakinoff。　　〃Some　liquid　that　is　in…
  tensely　radioactive；　but　what　it　is　I　know　not　at　all。　　Upon　the
  living　skin　it　acts　like　radium　raised　to　the　nth　power　and
  with　an　element　most　mysterious　added。　　The　solution　with
  which　I　treated　him；〃　he　pointed　to　Huldricksson；　〃I　had
  prepared　before　I　came　here；　from　certain　information　I
  had。　　It　is　largely　salts　of　radium　and　its　base　is　Loeb's
  formula　for　the　neutralization　of　radium　and　X…ray　burns。
  Taking　this　man　at　once；　before　the　degeneration　had　be…
  come　really　active；　I　could　negative　it。　　But　after　two　hours
  I　could　have　done　nothing。〃
  He　paused　a　moment。
  〃Next　I　studied　the　nature　of　these　luminous　walls。　　I
  concluded　that　whoever　had　made　them；　knew　the　secret　of
  the　Almighty's　manufacture　of　light　from　the　ether　itself！
  Colossal！　　Da！　　But　the　substance　of　these　blocks　confines　an
  atomichow　would　you　sayatomic　manipulation；　a
  conscious　arrangement　of　electrons；　light…emitting　and　per…
  haps　indefinitely　so。　　These　blocks　are　lamps　in　which　oil　and
  wick　are　electrons　drawing　light　waves　from　ether　itself！　　A
  Prometheus；　indeed；　this　discoverer！　　I　looked　at　my　watch
  and　that　little　guardian　warned　me　that　it　was　time　to　go。
  I　went。　　That　which　comes　forth　returnedthis　time　empty…
  handed。
  〃And　the　next　night　I　did　the　same　thing。　　Engrossed　in
  research；　I　let　the　moments　go　by　to　the　danger　point；　and
  scarcely　was　I　replaced　within　the　vault　when　the　shining
  thing　raced　over　the　walls；　and　in　its　grip　the　woman　and
  child
  〃Then　you　cameand　that　is　all。　　And　nowwhat　is　it
  you　know？〃
  Very　briefly　I　went　over　my　story。　　His　eyes　gleamed　now
  and　then；　but　he　did　not　interrupt　me。
  〃A　great　secret！　　A　colossal　secret！〃　he　muttered；　when　I
  had　ended。　　〃We　cannot　leave　it　hidden。〃
  〃The　first　thing　to　do　is　to　try　the　door；〃　said　Larry；　mat…
  ter　of　fact。
  〃There　is　no　use；　my　young　friend；〃　assured　Marakinoff
  mildly。
  〃Nevertheless　we'll　try；〃　said　Larry。　　We　retraced　our
  way　through　the　winding　tunnel　to　the　end；　but　soon　even
  O'Keefe　saw　that　any　idea　of　moving　the　slab　from　within
  was　hopeless。　　We　returned　to　the　Chamber　of　the　Pool。　　The
  pillars　of　light　were　fainter；　and　we　knew　that　the　moon　was
  sinking。　　On　the　world　outside　before　long　dawn　would　be
  breaking。　　I　began　to　feel　thirstand　the　blue　semblance　of
  water　within　the　silvery　rim　seemed　to　glint　mockingly　as
  my　eyes　rested　on　it。
  〃Da！〃　it　was　Marakinoff；　reading　my　thoughts　uncannily。
  〃Da！　　We　will　be　thirsty。　　And　it　will　be　very　bad　for　him　of
  us　who　loses　control　and　drinks　of　that；　my　friend。　　Da！〃
  Larry　threw　back　his　shoulders　as　though　shaking　a　burden
  from　them。
  〃This　place　would　give　an　angel　of　joy　the　willies；〃　he
  said。　　〃I　suggest　that　we　look　around　and　find　something　that
  will　take　us　somewhere。　　You　can　bet　the　people　that　built　it
  had　more　ways　of　getting　in　than　that　once…a…month　family
  entrance。　　Doc；　you　and　Olaf　take　the　left　wall；　the　professor
  and　I　will　take　the　right。〃
  He　loosened　one　of　his　automatics　with　a　suggestive　move…
  ment。
  〃After　you；　Professor；〃　he　bowed；　politely；　to　the　Russian。
  We　parted　and　set　forth。
  The　chamber　widened　out　from　the　portal　in　what　seemed
  to　be　the　arc　of　an　immense　circle。　　The　shining　walls　held　a
  perceptible　curve；　and　from　this　curvature　I　estimated　that
  the　roof　was　fully　three　hundred　feet　above　us。
  The　floor　was　of　smooth；　mosaic…fitted　blocks　of　a　faintly
  yellow　tinge。　　They　were　not　light…emitting　li