When　a　dog　barks　and　holds　his　head　up；　there　is　little　enough　to
  fear　from　him。　But　when　he　lowers　his　head　and　growlthen　look
  out。
  Mahan　knew　dogs。　In　stark　amazement　he　now　noted　Bruce's　strange
  attitude　toward　the　nurse。　Never　before　had　he　seen　the　dog　show
  active　hostility　toward　a　strangerleast　of　all　toward　a
  stranger　who　had　in　no　way　molested　him。　It　was　incredible　that
  the　wontedly　dignified　and　sweet…tempered　collie　had　thus
  returned　a　greeting。　Especially　from　a　woman！
  Mahan　had　often　seen　Red　Cross　nurses　stop　to　caress　Bruce。　He
  had　been　amused　at　the　dog's　almost　protective　cordiality　toward
  all　women；　whether　the　French　peasants　or　the　wearers　of　the
  brassard　of　mercy。
  Toward　menexcept　those　he　had　learned　to　look　on　as　friends
  the　collie　always　comported　himself　with　a　courteous　aloofness
  But　he　had　seemed　to　regard　every　woman　as　something　to　be
  humored　and　guarded　and　to　be　treated　with　the　same　cordial
  friendliness　that　he　bestowed　on　their　childrenwhich　is　the　way
  of　the　best　type　of　collie。　Yet　Bruce　had　actually　snarled　at
  this　woman　who　had　chirped　to　him　from　the　steps　of　the　church！
  And　he　showed　every　sign　of　following　up　the　challenge　by　still
  more　drastic　measures。
  〃Bruce！〃　called　Mahan　sharply。　〃BRUCE！　Shame！　Come　over　here！
  Come；　NOW！〃
  At　the　Sergeant's　vehement　summons　Bruce　turned　reluctantly　away
  from　the　foot　of　the　church　steps　and　came　across　the　street
  toward　the　estaminet。　He　came　slowly。　Midway　he　halted　and　looked
  back　over　his　shoulder　at　the　nurse；　his　fangs　glinting　once　more
  in　a　snarl。　At　a　second　and　more　emphatic　call　from　Mahan　the　dog
  continued　his　progress。
  The　nurse　had　started　back　in　alarm　at　the　collie's　angry
  demonstration。　Now；　gathering　up　her　work；　she　retreated　into　the
  church。
  〃I'm　sorry；　Miss！〃　Mahan　shouted　after　her。　〃I　never　saw　him　that
  way；　before；　when　a　lady　spoke　to　him。　If　it　was　any　dog　but　old
  Bruce；　I'd　give　him　a　whaling　for　acting　like　that　to　you。　I'm
  dead…sure　he　didn't　mean　any　harm。〃
  〃Oh；　I　was　going　in；　anyway；〃　replied　the　nurse；　from　the
  doorway。　〃It　is　of　no　consequence。〃
  She　spoke　nervously；　her　rich　contralto　voice　shaken　by　the　dog's
  fierce　show　of　enmity。　Then　she　vanished　into　the　church；　and
  Mahan　and　Vivier　took　turns　in　lecturing　Bruce　on　his　shameful
  dearth　of　courtesy。
  The　big　dog　paid　no　heed　at　all　to　his　friends'　discourse。　He　was
  staring　sullenly　at　the　doorway　through　which　the　nurse　had　gone。
  〃That's　one　swell　way　for　a　decently　bred　dog　to　treat　a　woman！〃
  Mahan　was　telling　him。　〃Least　of　all；　a　Red　Cross　nurse！　I'm
  clean　ashamed　of　you！〃
  Bruce　did　not　listen。　In　his　heart　he　was　still　angryand　very
  much　perplexed　as　well。　For　he　knew　what　these　stupid　humans　did
  not　seem　to　know。
  HE　KNEW　THE　RED　CROSS　NURSE　WAS　NO　WOMAN　AT　ALL；　BUT　A　MAN。
  Bruce　knew；　too；　that　the　nurse　did　not　belong　to　his　loved
  friends　of　the　Red　Cross。　For　his　uncanny　power　of　scent　told　him
  the　garments　worn　by　the　impostor　belonged　to　some　one　else。　To
  mere　humans；　a　small　and　slender　man；　who　can　act；　and　who　dons
  woman's　garb；　is　a　woman。　To　any　dog；　such　a　man　is　no　more　like
  a　woman　than　a　horse　with　a　lambskin　saddle…pad　is　a　lamb。　He　is
  merely　a　man　who　is　differently　dressed　from　other　meneven　as
  this　man　who　had　chirped　to　Bruce；　from　the　church　steps；　was　no
  less　a　man　for　the　costume　in　which　he　had　swathed　his　body。　Any
  dog；　at　a　glance　and　at　a　sniff；　would　have　known　that。
  Women；　for　one　thing；　do　not　usually　smoke　dozens　of　rank　cigars
  daily　for　years；　until　their　flesh　is　permeated　with　the　smell　of
  tobacco。　A　human　could　not　have　detected　such　a　smellsuch　a
  MAN…smell；on　the　person　who　had　chirped　to　Bruce。　Any　dog；
  twenty　feet　away；　would　have　noticed　it；　and　would　have　tabulated
  the　white…clad　masquerader　as　a　man。　Nor　do　a　woman's　hair　and
  skin　carry　the　faint　but　unmistakable　odor　of　barracks　and　of
  tent…life　and　of　martial　equipment；　as　did　this　man's。　The
  masquerader　was　evidently　not　only　a　man　but　a　soldier。
  Dogs；high…strung　dogs；do　not　like　to　have　tricks　played　on
  them；　least　of　all　by　strangers。　Bruce　seemed　to　take　the
  nurse…disguise　as　a　personal　affront　to　himself。　Then；　too；　the
  man　was　not　of　his　own　army。　On　the　contrary；　the　scent
  proclaimed　him　one　of　the　horde　whom　Bruce's　friends　so
  manifestly　hatedone　of　the　breed　that　had　more　than　once　fired
  on　the　dog。
  Diet　and　equipment　and　other　causes　give　a　German　soldier　a
  markedly　different　scent；　to　dogs'　miraculously　keen　nostrils；
  and　to　those　of　certain　humans；from　the　French　or　British　or
  American　troops。　War　records　prove　this。　Once　having　learned　the
  scent；　and　having　learned　to　detest　it；　Bruce　was　not　to　be
  deceived。
  For　all　these　reasons　he　had　snarled　loathingly　at　the　man　in
  white。　For　these　same　reasons　he　could　not　readily　forget　the
  incident；　but　continued　every　now　and　then　to　glance　curiously
  across　toward　the　church。
  Presently；not　relishing　the　rebukes　of　the　friends　who　had
  heretofore　pestered　him　by　overmuch　petting；the　collie　arose
  quietly　from　his　couch　of　trampled　earth　at　the　foot　of　the　stone
  bench　and　strolled　back　across　the　street。　Most　of　the　men　were
  too　busy；　talking；　to　note　Bruce's　departure。　But　Sergeant　Mahan
  caught　sight　of　him　just　as　the　dog　was　mounting　the　last　of　the
  steps　leading　into　the　church。
  As　a　rule；　when　Bruce　went　investigating；　he　walked　carelessly
  and　with　his　tail　slightly　a…wag。　Now　his　tail　was　stiff　as　an
  icicle；　and　he　moved　warily；　on　the　tips　of　his　toes。　His　tawny…
  maned　neck　was　low。　Mahan；　understanding　dogs；　did　not　like　the
  collie's　demeanor。　Remembering　that　the　nurse　had　entered　the
  church　a　few　minutes　earlier；　the　Sergeant　got　to　his　feet　and
  hastily　followed　Bruce。
  The　dog；　meanwhile；　had　passed　through　the　crazily　splintered
  doorway　and　had　paused　on　the　threshold　of　the　improvised
  hospital；　as　the　reek　of　iodoform　and　of　carbolic　smote　upon　his
  sensitive　nostrils。　In　front　of　him　was　the　stone…paved
  vestibule。　Beyond　was　the　interior　of　the　shattered　church；　lined
  now　with　double　rows　of　cots。
  Seated　on　a　camp…chair　in　the　shadowy　vestibule　was　the　pseudo
  Red　Cross　nurse。　At　sight　of　the　collie　the　nurse　got　up　in　some
  haste。　Bruce；　still　walking　stiff…legged；　drew　closer。
  Out　from　under　the　white　skirt　flashed　a　capable　and　solidly…
  shod　foot。　In　a　swinging　kick；　the　foot　let　drive　at　the　oncoming
  dog。　Before　Bruce　could　dodge　or　could　so　much　as　guess　what　was
  coming；the　kick　smote　him　with　agonizing　force；　square　on　the
  shoulder。
  To　a　spirited　collie；　a　kick　carries　more　than　the　mere　pain　of
  its　inflicting。　It　is　a　grossly　unforgivable　affront　as　wellas
  many　a　tramp　and　thief　have　learned；　at　high　cost。
  By　the　time　the　kick　had　fairly　landed；　Bruce　had　recovered　from
  his　instant　of　incredulous　surprise；　and　with　lightning　swiftness
  he　hurled　himself　at　his　assailant。
  No　bark　or　growl　heralded　the　murderous　throatlunge。　It　was　all
  the　more　terrible　for　the　noiselessness　wherewith　it　was
  delivered。　The　masquerading　man　saw　it　coming；　just　too　late　to
  guard　against　it。　He　lurched　backward；　belatedly　throwing　both
  hands　up　to　defend　his　throat。　It　was　the　involuntary　backward
  step　which　saved　his　jugular。　For　his　heel　caught　in　the　hem　of
  his　white　skirt。　And　wholly　off　balance；　he　pitched　headlong　to
  the　floor。
  This　jerky　shift　of　position；　on　the　part　of　the　foe；　spoiled
  Bruce's　aim。　His　fearful　jaws　snapped　together　harmlessly　in
  empty　air　at　a　spot　where；　a　fraction　of　a　second　earlier；　the
  other's　throat　had　been。　Down　crashed　the　disguised　man。　And　atop
  of　him　the　furious　dog　hurled　himself；　seeking　a　second　time　the
  throatgrip　he　had　so　narrowly　missed。
  At　this　point　on　the　program　Sergeant　Mahan　arrived　just　in　time
  to　bury　both　hands　in　the　mass　of　Bruce's　furry　ruff　and　to　drag
  the　snarlingly　rabid　dog　back　from　his　prey。
  The　place　was　in　an　uproar。　Nurses　and　doctors　came　rushing　out
  into　the　vestibule；　sick　and　wounded　men　sat　up　on　their　cots　and
  eagerly　craned　their　necks　to　catch　sight　of　the　scrimmage。
  Soldiers　ran　in　from　the　street。
  Strong　as　he　was；　Mahan　had　both　hands　full　in　holding　the
  frantic　Bruce　back　from　his　enemy。　Under　the　insult　of　the　kick
  from　this　masquerader；　whom　he　had　already　recognized　as　a　foe；
  the　collie　had　temporarily　lost　every　vestige　of　his　stately
  dignity。　He　was　for　the　moment　merely　a　wild　beast；　seeking
  revenge　for　a　brutal　injury。　He　writhed　and　fought　in　Mahan's
  grasp。　Never　once　did　he　seek　to　attack　the　struggling　man　who
  held　him。　But　he　strained　every　giant　sinew　to　get　at　the　foe　who
  had　kicked　him。
  The　dog's　opponent　scrambled　to　his　feet；　helped　by　a　dozen
  willing　hands　and　accosted　by　as　many　solicitous　voices。　The
  victim's　face　was　bone…gray　with　terror。　His　lips　twitched
  convu