white　face　of　the　Scotch　aristocrat　and　her　lover；　the　Irish　adventurer；　like　old　portraits　in　a　dark　house。　　The　long　silence　was　full　of　formless　historical　memories　of　murdered　husbands　and　poisonous　paramours。　　　　　In　the　centre　of　this　morbid　silence　an　innocent　voice　said：　〃Was　it　a　very　long　cigar？〃　　　　　The　change　of　thought　was　so　sharp　that　they　had　to　look　round　to　see　who　had　spoken。　　　　　〃I　mean；〃　said　little　Father　Brown；　from　the　corner　of　the　room；　〃I　mean　that　cigar　Mr。　Brayne　is　finishing。　　It　seems　nearly　as　long　as　a　walking…stick。〃　　　　　Despite　the　irrelevance　there　was　assent　as　well　as　irritation　in　Valentin's　face　as　he　lifted　his　head。　　　　　〃Quite　right；〃　he　remarked　sharply。　　〃Ivan；　go　and　see　about　Mr。　Brayne　again；　and　bring　him　here　at　once。〃　　　　　The　instant　the　factotum　had　closed　the　door；　Valentin　addressed　the　girl　with　an　entirely　new　earnestness。　　　　　〃Lady　Margaret；〃　he　said；　〃we　all　feel；　I　am　sure；　both　gratitude　and　admiration　for　your　act　in　rising　above　your　lower　dignity　and　explaining　the　Commandant's　conduct。　　But　there　is　a　hiatus　still。　　Lord　Galloway；　I　understand；　met　you　passing　from　the　study　to　the　drawing…room；　and　it　was　only　some　minutes　afterwards　that　he　found　the　garden　and　the　Commandant　still　walking　there。〃　　　　　〃You　have　to　remember；〃　replied　Margaret；　with　a　faint　irony　in　her　voice；　〃that　I　had　just　refused　him；　so　we　should　scarcely　have　come　back　arm　in　arm。　　He　is　a　gentleman；　anyhow；　and　he　loitered　behindand　so　got　charged　with　murder。〃　　　　　〃In　those　few　moments；〃　said　Valentin　gravely；　〃he　might　really〃　　　　　The　knock　came　again；　and　Ivan　put　in　his　scarred　face。　　　　　〃Beg　pardon；　sir；〃　he　said；　〃but　Mr。　Brayne　has　left　the　house。〃　　　　　〃Left！〃　cried　Valentin；　and　rose　for　the　first　time　to　his　feet。　　　　　〃Gone。　　Scooted。　　Evaporated；〃　replied　Ivan　in　humorous　French。　　〃His　hat　and　coat　are　gone；　too；　and　I'll　tell　you　something　to　cap　it　all。　　I　ran　outside　the　house　to　find　any　traces　of　him；　and　I　found　one；　and　a　big　trace；　too。〃　　　　　〃What　do　you　mean？〃　asked　Valentin。　　　　　〃I'll　show　you；〃　said　his　servant；　and　reappeared　with　a　flashing　naked　cavalry　sabre；　streaked　with　blood　about　the　point　and　edge。　　Everyone　in　the　room　eyed　it　as　if　it　were　a　thunderbolt；　but　the　experienced　Ivan　went　on　quite　quietly：　　　　　〃I　found　this；〃　he　said；　〃flung　among　the　bushes　fifty　yards　up　the　road　to　Paris。　　In　other　words；　I　found　it　just　where　your　respectable　Mr。　Brayne　threw　it　when　he　ran　away。〃　　　　　There　was　again　a　silence；　but　of　a　new　sort。　　Valentin　took　the　sabre；　examined　it；　reflected　with　unaffected　concentration　of　thought；　and　then　turned　a　respectful　face　to　O'Brien。　〃Commandant；〃　he　said；　〃we　trust　you　will　always　produce　this　weapon　if　it　is　wanted　for　police　examination。　　Meanwhile；〃　he　added；　slapping　the　steel　back　in　the　ringing　scabbard；　〃let　me　return　you　your　sword。〃　　　　　At　the　military　symbolism　of　the　action　the　audience　could　hardly　refrain　from　applause。　　　　　For　Neil　O'Brien；　indeed；　that　gesture　was　the　turning…point　of　existence。　　By　the　time　he　was　wandering　in　the　mysterious　garden　again　in　the　colours　of　the　morning　the　tragic　futility　of　his　ordinary　mien　had　fallen　from　him；　he　was　a　man　with　many　reasons　for　happiness。　　Lord　Galloway　was　a　gentleman；　and　had　offered　him　an　apology。　　Lady　Margaret　was　something　better　than　a　lady；　a　woman　at　least；　and　had　perhaps　given　him　something　better　than　an　apology；　as　they　drifted　among　the　old　flowerbeds　before　breakfast。　　The　whole　company　was　more　lighthearted　and　humane；　for　though　the　riddle　of　the　death　remained；　the　load　of　suspicion　was　lifted　off　them　all；　and　sent　flying　off　to　Paris　with　the　strange　millionairea　man　they　hardly　knew。　　The　devil　was　cast　out　of　the　househe　had　cast　himself　out。　　　　　Still；　the　riddle　remained；　and　when　O'Brien　threw　himself　on　a　garden　seat　beside　Dr。　Simon；　that　keenly　scientific　person　at　once　resumed　it。　　He　did　not　get　much　talk　out　of　O'Brien；　whose　thoughts　were　on　pleasanter　things。　　　　　〃I　can't　say　it　interests　me　much；〃　said　the　Irishman　frankly；　〃especially　as　it　seems　pretty　plain　now。　　Apparently　Brayne　hated　this　stranger　for　some　reason；　lured　him　into　the　garden；　and　killed　him　with　my　sword。　　Then　he　fled　to　the　city；　tossing　the　sword　away　as　he　went。　　By　the　way；　Ivan　tells　me　the　dead　man　had　a　Yankee　dollar　in　his　pocket。　　So　he　was　a　countryman　of　Brayne's；　and　that　seems　to　clinch　it。　　I　don't　see　any　difficulties　about　the　business。〃　　　　　〃There　are　five　colossal　difficulties；〃　said　the　doctor　quietly；　〃like　high　walls　within　walls。　　Don't　mistake　me。　　I　don't　doubt　that　Brayne　did　it；　his　flight；　I　fancy；　proves　that。　But　as　to　how　he　did　it。　　First　difficulty：　Why　should　a　man　kill　another　man　with　a　great　hulking　sabre；　when　he　can　almost　kill　him　with　a　pocket　knife　and　put　it　back　in　his　pocket？　　Second　difficulty：　Why　was　there　no　noise　or　outcry？　　Does　a　man　commonly　see　another　come　up　waving　a　scimitar　and　offer　no　remarks？　　Third　difficulty：　A　servant　watched　the　front　door　all　the　evening；　and　a　rat　cannot　get　into　Valentin's　garden　anywhere。　　How　did　the　dead　man　get　into　the　garden？　　Fourth　difficulty：　Given　the　same　conditions；　how　did　Brayne　get　out　of　the　garden？〃　　　　　〃And　the　fifth；〃　said　Neil；　with　eyes　fixed　on　the　English　priest　who　was　coming　slowly　up　the　path。　　　　　〃Is　a　trifle；　I　suppose；〃　said　the　doctor；　〃but　I　think　an　odd　one。　　When　I　first　saw　how　the　head　had　been　slashed；　I　supposed　the　assassin　had　struck　more　than　once。　　But　on　examination　I　found　many　cuts　across　the　truncated　section；　in　other　words；　they　were　struck　after　the　head　was　off。　　Did　Brayne　hate　his　foe　so　fiendishly　that　he　stood　sabring　his　body　in　the　moonlight？〃　　　　　〃Horrible！〃　said　O'Brien；　and　shuddered。　　　　　The　little　priest；　Brown；　had　arrived　while　they　were　talking；　and　had　waited；　with　characteristic　shyness；　till　they　had　finished。　　Then　he　said　awkwardly：　　　　　〃I　say；　I'm　sorry　to　interrupt。　　But　I　was　sent　to　tell　you　the　news！〃　　　　　〃News？〃　repeated　Simon；　and　stared　at　him　rather　painfully　through　his　glasses。　　　　　〃Yes；　I'm　sorry；〃　said　Father　Brown　mildly。　　〃There's　been　another　murder；　you　know。〃　　　　　Both　men　on　the　seat　sprang　up；　leaving　it　rocking。　　　　　〃And；　what's　stranger　still；〃　continued　the　priest；　with　his　dull　eye　on　the　rhododendrons；　〃it's　the　same　disgusting　sort；　it's　another　beheading。　　They　found　the　second　head　actually　bleeding　into　the　river；　a　few　yards　along　Brayne's　road　to　Paris；　so　they　suppose　that　he〃　　　　　〃Great　Heaven！〃　cried　O'Brien。　　〃Is　Brayne　a　monomaniac？〃　　　　　〃There　are　American　vendettas；〃　said　the　priest　impassively。　Then　he　added：　〃They　want　you　to　come　to　the　library　and　see　it。〃　　　　　Commandant　O'Brien　followed　the　others　towards　the　inquest；　feeling　decidedly　sick。　　As　a　soldier；　he　loathed　all　this　secretive　carnage；　where　were　these　extravagant　amputations　going　to　stop？　　First　one　head　was　hacked　off；　and　then　another；　in　this　case　（he　told　himself　bitterly）　it　was　not　true　that　two　heads　were　better　than　one。　　As　he　crossed　the　study　he　almost　staggered　at　a　shocking　coincidence。　　Upon　Valentin's　table　lay　the　coloured　picture　of　yet　a　third　bleeding　head；　and　it　was　the　head　of　Valentin　himself。　　A　second　glance　showed　him　it　was　only　a　Nationalist　paper；　called　The　Guillotine；　which　every　week　showed　one　of　its　political　opponents　with　rolling　eyes　and　writhing　features　just　after　execution；　for　Valentin　was　an　anti…clerical　of　some　note。　　But　O'Brien　was　an　Irishman；　with　a　kind　of　chastity　even　in　his　sins；　and　his　gorge　rose　against　that　great　brutality　of　the　intellect　which　belongs　only　to　France。　　He　felt　Paris　as　a　whole；　from　the　grotesques　on　the　Gothic　churches　to　the　gross　caricatures　in　the　newspapers。　　He　remembered　the　gigantic　jests　of　the　Revolution。　　He　saw　the　whole　city　as　one　ugly　energy；　from　the　sanguinary　sketch　lying　on　Valentin's　table　up　to　where；　above　a　mountain　and　forest　of　gargoyles；　the　great　devil　grins　on　Notre　Dame。　　　　　The　library　was　long；　low；　and　dark；　what　light　entered　it　shot　from　under　low　blinds　and　had　still　some　of　the　ruddy　tinge　of　morning。　　Valentin　and　his　servant　Ivan　were　waiting　for　them　at　the　upper　end　of　a　long；　slightly…sloping　desk；　on　which　lay　the　mortal　remains；　looking　enormous　in　the　twilight。　　The　big　black　figure　and　yellow　face　of　the　man　found　in　the　garden　confronted　them　essentially　unchanged。　　The　second　head；　which　had　been　fished　from　among　the　river　reeds　that　morning；　lay　streaming　and　dripping　beside　it；　Valentin's　men　were　still　seeking　to　recover　the　rest　of　this　second　corpse；　which　was　supposed　to　be　afloat。　Father　Brown；　who　did　not　seem　to　share　O'Brien's　sensibilities　in　the　least；　went　up　to　the　second　head　and　examined　it　with　his　blinking　care。　　It　was　little　more　than　a　mop　of　wet　white　hair；　fringed　with　silver　fire　in　the　red　and　level　morning　light；　the　face；　which　seemed　of　an　ugly；　empurpled　and　perhaps　criminal　type；　had　been　much　battered　against　trees　or　stones　as　it　tossed　in　the　water。　　　　　〃Good　morning；　Commandant　O'Brien；〃　said　Valentin；　with　quiet　cordiality。　　〃You　have　heard　of　Brayne's　last　experiment　in　butchery；　I　suppose？〃　　　　　Father　Brown　was　still　bending　over　the　head　with　white　hair；　and　h