ent　in　butchery；　I　suppose？〃　　　　　Father　Brown　was　still　bending　over　the　head　with　white　hair；　and　he　said；　without　looking　up：　　　　　〃I　suppose　it　is　quite　certain　that　Brayne　cut　off　this　head；　too。〃　　　　　〃Well；　it　seems　common　sense；〃　said　Valentin；　with　his　hands　in　his　pockets。　　〃Killed　in　the　same　way　as　the　other。　　Found　within　a　few　yards　of　the　other。　　And　sliced　by　the　same　weapon　which　we　know　he　carried　away。〃　　　　　〃Yes；　yes；　I　know；〃　replied　Father　Brown　submissively。　　〃Yet；　you　know；　I　doubt　whether　Brayne　could　have　cut　off　this　head。〃　　　　　〃Why　not？〃　inquired　Dr。　Simon；　with　a　rational　stare。　　　　　〃Well；　doctor；〃　said　the　priest；　looking　up　blinking；　〃can　a　man　cut　off　his　own　head？　　I　don't　know。〃　　　　　O'Brien　felt　an　insane　universe　crashing　about　his　ears；　but　the　doctor　sprang　forward　with　impetuous　practicality　and　pushed　back　the　wet　white　hair。　　　　　〃Oh；　there's　no　doubt　it's　Brayne；〃　said　the　priest　quietly。　〃He　had　exactly　that　chip　in　the　left　ear。〃　　　　　The　detective；　who　had　been　regarding　the　priest　with　steady　and　glittering　eyes；　opened　his　clenched　mouth　and　said　sharply：　〃You　seem　to　know　a　lot　about　him；　Father　Brown。〃　　　　　〃I　do；〃　said　the　little　man　simply。　　〃I've　been　about　with　him　for　some　weeks。　　He　was　thinking　of　joining　our　church。〃　　　　　The　star　of　the　fanatic　sprang　into　Valentin's　eyes；　he　strode　towards　the　priest　with　clenched　hands。　　〃And；　perhaps；〃　he　cried；　with　a　blasting　sneer；　〃perhaps　he　was　also　thinking　of　leaving　all　his　money　to　your　church。〃　　　　　〃Perhaps　he　was；〃　said　Brown　stolidly；　〃it　is　possible。〃　　　　　〃In　that　case；〃　cried　Valentin；　with　a　dreadful　smile；　〃you　may　indeed　know　a　great　deal　about　him。　　About　his　life　and　about　his〃　　　　　Commandant　O'Brien　laid　a　hand　on　Valentin's　arm。　　〃Drop　that　slanderous　rubbish；　Valentin；〃　he　said；　〃or　there　may　be　more　swords　yet。〃　　　　　But　Valentin　（under　the　steady；　humble　gaze　of　the　priest）　had　already　recovered　himself。　　〃Well；〃　he　said　shortly；　〃people's　private　opinions　can　wait。　　You　gentlemen　are　still　bound　by　your　promise　to　stay；　you　must　enforce　it　on　yourselvesand　on　each　other。　　Ivan　here　will　tell　you　anything　more　you　want　to　know；　I　must　get　to　business　and　write　to　the　authorities。　　We　can't　keep　this　quiet　any　longer。　　I　shall　be　writing　in　my　study　if　there　is　any　more　news。〃　　　　　〃Is　there　any　more　news；　Ivan？〃　asked　Dr。　Simon；　as　the　chief　of　police　strode　out　of　the　room。　　　　　〃Only　one　more　thing；　I　think；　sir；〃　said　Ivan；　wrinkling　up　his　grey　old　face；　〃but　that's　important；　too；　in　its　way。　There's　that　old　buffer　you　found　on　the　lawn；〃　and　he　pointed　without　pretence　of　reverence　at　the　big　black　body　with　the　yellow　head。　　〃We've　found　out　who　he　is；　anyhow。〃　　　　　〃Indeed！〃　cried　the　astonished　doctor；　〃and　who　is　he？〃　　　　　〃His　name　was　Arnold　Becker；〃　said　the　under…detective；　〃though　he　went　by　many　aliases。　　He　was　a　wandering　sort　of　scamp；　and　is　known　to　have　been　in　America；　so　that　was　where　Brayne　got　his　knife　into　him。　　We　didn't　have　much　to　do　with　him　ourselves；　for　he　worked　mostly　in　Germany。　　We've　communicated；　of　course；　with　the　German　police。　　But；　oddly　enough；　there　was　a　twin　brother　of　his；　named　Louis　Becker；　whom　we　had　a　great　deal　to　do　with。　　In　fact；　we　found　it　necessary　to　guillotine　him　only　yesterday。　　Well；　it's　a　rum　thing；　gentlemen；　but　when　I　saw　that　fellow　flat　on　the　lawn　I　had　the　greatest　jump　of　my　life。　　If　I　hadn't　seen　Louis　Becker　guillotined　with　my　own　eyes；　I'd　have　sworn　it　was　Louis　Becker　lying　there　in　the　grass。　　Then；　of　course；　I　remembered　his　twin　brother　in　Germany；　and　following　up　the　clue〃　　　　　The　explanatory　Ivan　stopped；　for　the　excellent　reason　that　nobody　was　listening　to　him。　　The　Commandant　and　the　doctor　were　both　staring　at　Father　Brown；　who　had　sprung　stiffly　to　his　feet；　and　was　holding　his　temples　tight　like　a　man　in　sudden　and　violent　pain。　　　　　〃Stop；　stop；　stop！〃　he　cried；　〃stop　talking　a　minute；　for　I　see　half。　　Will　God　give　me　strength？　　Will　my　brain　make　the　one　jump　and　see　all？　　Heaven　help　me！　　I　used　to　be　fairly　good　at　thinking。　　I　could　paraphrase　any　page　in　Aquinas　once。　　Will　my　head　splitor　will　it　see？　　I　see　halfI　only　see　half。〃　　　　　He　buried　his　head　in　his　hands；　and　stood　in　a　sort　of　rigid　torture　of　thought　or　prayer；　while　the　other　three　could　only　go　on　staring　at　this　last　prodigy　of　their　wild　twelve　hours。　　　　　When　Father　Brown's　hands　fell　they　showed　a　face　quite　fresh　and　serious；　like　a　child's。　　He　heaved　a　huge　sigh；　and　said：　〃Let　us　get　this　said　and　done　with　as　quickly　as　possible。　　Look　here；　this　will　be　the　quickest　way　to　convince　you　all　of　the　truth。〃　　He　turned　to　the　doctor。　　〃Dr。　Simon；〃　he　said；　〃you　have　a　strong　head…piece；　and　I　heard　you　this　morning　asking　the　five　hardest　questions　about　this　business。　　Well；　if　you　will　ask　them　again；　I　will　answer　them。〃　　　　　Simon's　pince…nez　dropped　from　his　nose　in　his　doubt　and　wonder；　but　he　answered　at　once。　　〃Well；　the　first　question；　you　know；　is　why　a　man　should　kill　another　with　a　clumsy　sabre　at　all　when　a　man　can　kill　with　a　bodkin？〃　　　　　〃A　man　cannot　behead　with　a　bodkin；〃　said　Brown　calmly；　〃and　for　this　murder　beheading　was　absolutely　necessary。〃　　　　　〃Why？〃　asked　O'Brien；　with　interest。　　　　　〃And　the　next　question？〃　asked　Father　Brown。　　　　　〃Well；　why　didn't　the　man　cry　out　or　anything？〃　asked　the　doctor；　〃sabres　in　gardens　are　certainly　unusual。〃　　　　　〃Twigs；〃　said　the　priest　gloomily；　and　turned　to　the　window　which　looked　on　the　scene　of　death。　　〃No　one　saw　the　point　of　the　twigs。　　Why　should　they　lie　on　that　lawn　（look　at　it）　so　far　from　any　tree？　　They　were　not　snapped　off；　they　were　chopped　off。　　The　murderer　occupied　his　enemy　with　some　tricks　with　the　sabre；　showing　how　he　could　cut　a　branch　in　mid…air；　or　what…not。　　Then；　while　his　enemy　bent　down　to　see　the　result；　a　silent　slash；　and　the　head　fell。〃　　　　　〃Well；〃　said　the　doctor　slowly；　〃that　seems　plausible　enough。　But　my　next　two　questions　will　stump　anyone。〃　　　　　The　priest　still　stood　looking　critically　out　of　the　window　and　waited。　　　　　〃You　know　how　all　the　garden　was　sealed　up　like　an　air…tight　chamber；〃　went　on　the　doctor。　　〃Well；　how　did　the　strange　man　get　into　the　garden？〃　　　　　Without　turning　round；　the　little　priest　answered：　〃There　never　was　any　strange　man　in　the　garden。〃　　　　　There　was　a　silence；　and　then　a　sudden　cackle　of　almost　childish　laughter　relieved　the　strain。　　The　absurdity　of　Brown's　remark　moved　Ivan　to　open　taunts。　　　　　〃Oh！〃　he　cried；　〃then　we　didn't　lug　a　great　fat　corpse　on　to　a　sofa　last　night？　　He　hadn't　got　into　the　garden；　I　suppose？〃　　　　　〃Got　into　the　garden？〃　repeated　Brown　reflectively。　　〃No；　not　entirely。〃　　　　　〃Hang　it　all；〃　cried　Simon；　〃a　man　gets　into　a　garden；　or　he　doesn't。〃　　　　　〃Not　necessarily；〃　said　the　priest；　with　a　faint　smile。　　〃What　is　the　nest　question；　doctor？〃　　　　　〃I　fancy　you're　ill；〃　exclaimed　Dr。　Simon　sharply；　〃but　I'll　ask　the　next　question　if　you　like。　　How　did　Brayne　get　out　of　the　garden？〃　　　　　〃He　didn't　get　out　of　the　garden；〃　said　the　priest；　still　looking　out　of　the　window。　　　　　〃Didn't　get　out　of　the　garden？〃　exploded　Simon。　　　　　〃Not　completely；〃　said　Father　Brown。　　　　　Simon　shook　his　fists　in　a　frenzy　of　French　logic。　　〃A　man　gets　out　of　a　garden；　or　he　doesn't；〃　he　cried。　　　　　〃Not　always；〃　said　Father　Brown。　　　　　Dr。　Simon　sprang　to　his　feet　impatiently。　　〃I　have　no　time　to　spare　on　such　senseless　talk；〃　he　cried　angrily。　　〃If　you　can't　understand　a　man　being　on　one　side　of　a　wall　or　the　other；　I　won't　trouble　you　further。〃　　　　　〃Doctor；〃　said　the　cleric　very　gently；　〃we　have　always　got　on　very　pleasantly　together。　　If　only　for　the　sake　of　old　friendship；　stop　and　tell　me　your　fifth　question。〃　　　　　The　impatient　Simon　sank　into　a　chair　by　the　door　and　said　briefly：　〃The　head　and　shoulders　were　cut　about　in　a　queer　way。　It　seemed　to　be　done　after　death。〃　　　　　〃Yes；〃　said　the　motionless　priest；　〃it　was　done　so　as　to　make　you　assume　exactly　the　one　simple　falsehood　that　you　did　assume。　It　was　done　to　make　you　take　for　granted　that　the　head　belonged　to　the　body。〃　　　　　The　borderland　of　the　brain；　where　all　the　monsters　are　made；　moved　horribly　in　the　Gaelic　O'Brien。　　He　felt　the　chaotic　presence　of　all　the　horse…men　and　fish…women　that　man's　unnatural　fancy　has　begotten。　　A　voice　older　than　his　first　fathers　seemed　saying　in　his　ear：　〃Keep　out　of　the　monstrous　garden　where　grows　the　tree　with　double　fruit。　　Avoid　the　evil　garden　where　died　the　man　with　two　heads。〃　　Yet；　while　these　shameful　symbolic　shapes　passed　across　the　ancient　mirror　of　his　Irish　soul；　his　Frenchified　intellect　was　quite　alert；　and　was　watching　the　odd　priest　as　closely　and　incredulously　as　all　the　rest。　　　　　Father　Brown　had　turned　round　at　last；　and　stood　against　the　window；　with　his　face　in　dense　shadow；　but　even　in　that　shadow　they　could　see　it　was　pale　as　ashes。　　Nevertheless；　he　spoke　quite　sensibly；　as　if　there　were　no　Gaelic　souls　on　earth。　　　　　〃Gentlemen；〃　he　said；　〃you　did　not　find　the　strange　body　of　Becker　in　the　garden。　　You　did　not　find　any　strange　body　in　the　garden。　　In　face　of　Dr。　Simon's　rationalism；　I　still　affirm　that　Becker　was　only　partly　present。　　Look　here！〃　（pointing　to　the　black　bulk　of　the　mysterious　corpse）　〃you　never　saw　that　man　in