saw　the　Duchess　of　Mont　St。　Michel；　black…eyed　and　opulent；　and　with　her　her　two　daughters；　black…eyed　and　opulent　also。　　He　saw　Dr。　Simon；　a　typical　French　scientist；　with　glasses；　a　pointed　brown　beard；　and　a　forehead　barred　with　those　parallel　wrinkles　which　are　the　penalty　of　superciliousness；　since　they　come　through　constantly　elevating　the　eyebrows。　　He　saw　Father　Brown；　of　Cobhole；　in　Essex；　whom　he　had　recently　met　in　England。　　He　sawperhaps　with　more　interest　than　any　of　thesea　tall　man　in　uniform；　who　had　bowed　to　the　Galloways　without　receiving　any　very　hearty　acknowledgment；　and　who　now　advanced　alone　to　pay　his　respects　to　his　host。　　This　was　Commandant　O'Brien；　of　the　French　Foreign　Legion。　　He　was　a　slim　yet　somewhat　swaggering　figure；　clean…shaven；　dark…haired；　and　blue…eyed；　and；　as　seemed　natural　in　an　officer　of　that　famous　regiment　of　victorious　failures　and　successful　suicides；　he　had　an　air　at　once　dashing　and　melancholy。　　He　was　by　birth　an　Irish　gentleman；　and　in　boyhood　had　known　the　Gallowaysespecially　Margaret　Graham。　　He　had　left　his　country　after　some　crash　of　debts；　and　now　expressed　his　complete　freedom　from　British　etiquette　by　swinging　about　in　uniform；　sabre　and　spurs。　　When　he　bowed　to　the　Ambassador's　family；　Lord　and　Lady　Galloway　bent　stiffly；　and　Lady　Margaret　looked　away。　　　　　But　for　whatever　old　causes　such　people　might　be　interested　in　each　other；　their　distinguished　host　was　not　specially　interested　in　them。　　No　one　of　them　at　least　was　in　his　eyes　the　guest　of　the　evening。　　Valentin　was　expecting；　for　special　reasons；　a　man　of　world…wide　fame；　whose　friendship　he　had　secured　during　some　of　his　great　detective　tours　and　triumphs　in　the　United　States。　　He　was　expecting　Julius　K。　Brayne；　that　multi…millionaire　whose　colossal　and　even　crushing　endowments　of　small　religions　have　occasioned　so　much　easy　sport　and　easier　solemnity　for　the　American　and　English　papers。　　Nobody　could　quite　make　out　whether　Mr。　Brayne　was　an　atheist　or　a　Mormon　or　a　Christian　Scientist；　but　he　was　ready　to　pour　money　into　any　intellectual　vessel；　so　long　as　it　was　an　untried　vessel。　　One　of　his　hobbies　was　to　wait　for　the　American　Shakespearea　hobby　more　patient　than　angling。　He　admired　Walt　Whitman；　but　thought　that　Luke　P。　Tanner；　of　Paris；　Pa。；　was　more　〃progressive〃　than　Whitman　any　day。　　He　liked　anything　that　he　thought　〃progressive。〃　　He　thought　Valentin　〃progressive；〃　thereby　doing　him　a　grave　injustice。　　　　　The　solid　appearance　of　Julius　K。　Brayne　in　the　room　was　as　decisive　as　a　dinner　bell。　　He　had　this　great　quality；　which　very　few　of　us　can　claim；　that　his　presence　was　as　big　as　his　absence。　He　was　a　huge　fellow；　as　fat　as　he　was　tall；　clad　in　complete　evening　black；　without　so　much　relief　as　a　watch…chain　or　a　ring。　His　hair　was　white　and　well　brushed　back　like　a　German's；　his　face　was　red；　fierce　and　cherubic；　with　one　dark　tuft　under　the　lower　lip　that　threw　up　that　otherwise　infantile　visage　with　an　effect　theatrical　and　even　Mephistophelean。　　Not　long；　however；　did　that　salon　merely　stare　at　the　celebrated　American；　his　lateness　had　already　become　a　domestic　problem；　and　he　was　sent　with　all　speed　into　the　dining…room　with　Lady　Galloway　on　his　arm。　　　　　Except　on　one　point　the　Galloways　were　genial　and　casual　enough。　　So　long　as　Lady　Margaret　did　not　take　the　arm　of　that　adventurer　O'Brien；　her　father　was　quite　satisfied；　and　she　had　not　done　so；　she　had　decorously　gone　in　with　Dr。　Simon。　Nevertheless；　old　Lord　Galloway　was　restless　and　almost　rude。　　He　was　diplomatic　enough　during　dinner；　but　when；　over　the　cigars；　three　of　the　younger　menSimon　the　doctor；　Brown　the　priest；　and　the　detrimental　O'Brien；　the　exile　in　a　foreign　uniformall　melted　away　to　mix　with　the　ladies　or　smoke　in　the　conservatory；　then　the　English　diplomatist　grew　very　undiplomatic　indeed。　　He　was　stung　every　sixty　seconds　with　the　thought　that　the　scamp　O'Brien　might　be　signalling　to　Margaret　somehow；　he　did　not　attempt　to　imagine　how。　　He　was　left　over　the　coffee　with　Brayne；　the　hoary　Yankee　who　believed　in　all　religions；　and　Valentin；　the　grizzled　Frenchman　who　believed　in　none。　　They　could　argue　with　each　other；　but　neither　could　appeal　to　him。　　After　a　time　this　〃progressive〃　logomachy　had　reached　a　crisis　of　tedium；　Lord　Galloway　got　up　also　and　sought　the　drawing…room。　　He　lost　his　way　in　long　passages　for　some　six　or　eight　minutes：　till　he　heard　the　high…pitched；　didactic　voice　of　the　doctor；　and　then　the　dull　voice　of　the　priest；　followed　by　general　laughter。　　They　also；　he　thought　with　a　curse；　were　probably　arguing　about　〃science　and　religion。〃　　But　the　instant　he　opened　the　salon　door　he　saw　only　one　thinghe　saw　what　was　not　there。　　He　saw　that　Commandant　O'Brien　was　absent；　and　that　Lady　Margaret　was　absent　too。　　　　　Rising　impatiently　from　the　drawing…room；　as　he　had　from　the　dining…room；　he　stamped　along　the　passage　once　more。　　His　notion　of　protecting　his　daughter　from　the　Irish…Algerian　n'er…do…weel　had　become　something　central　and　even　mad　in　his　mind。　　As　he　went　towards　the　back　of　the　house；　where　was　Valentin's　study；　he　was　surprised　to　meet　his　daughter；　who　swept　past　with　a　white；　scornful　face；　which　was　a　second　enigma。　　If　she　had　been　with　O'Brien；　where　was　O'Brien！　　If　she　had　not　been　with　O'Brien；　where　had　she　been？　　With　a　sort　of　senile　and　passionate　suspicion　he　groped　his　way　to　the　dark　back　parts　of　the　mansion；　and　eventually　found　a　servants'　entrance　that　opened　on　to　the　garden。　　The　moon　with　her　scimitar　had　now　ripped　up　and　rolled　away　all　the　storm…wrack。　　The　argent　light　lit　up　all　four　corners　of　the　garden。　　A　tall　figure　in　blue　was　striding　across　the　lawn　towards　the　study　door；　a　glint　of　moonlit　silver　on　his　facings　picked　him　out　as　Commandant　O'Brien。　　　　　He　vanished　through　the　French　windows　into　the　house；　leaving　Lord　Galloway　in　an　indescribable　temper；　at　once　virulent　and　vague。　　The　blue…and…silver　garden；　like　a　scene　in　a　theatre；　seemed　to　taunt　him　with　all　that　tyrannic　tenderness　against　which　his　worldly　authority　was　at　war。　　The　length　and　grace　of　the　Irishman's　stride　enraged　him　as　if　he　were　a　rival　instead　of　a　father；　the　moonlight　maddened　him。　　He　was　trapped　as　if　by　magic　into　a　garden　of　troubadours；　a　Watteau　fairyland；　and；　willing　to　shake　off　such　amorous　imbecilities　by　speech；　he　stepped　briskly　after　his　enemy。　　As　he　did　so　he　tripped　over　some　tree　or　stone　in　the　grass；　looked　down　at　it　first　with　irritation　and　then　a　second　time　with　curiosity。　　The　next　instant　the　moon　and　the　tall　poplars　looked　at　an　unusual　sight　an　elderly　English　diplomatist　running　hard　and　crying　or　bellowing　as　he　ran。　　　　　His　hoarse　shouts　brought　a　pale　face　to　the　study　door；　the　beaming　glasses　and　worried　brow　of　Dr。　Simon；　who　heard　the　nobleman's　first　clear　words。　　Lord　Galloway　was　crying：　〃A　corpse　in　the　grassa　blood…stained　corpse。〃　　O'Brien　at　last　had　gone　utterly　out　of　his　mind。　　　　　〃We　must　tell　Valentin　at　once；〃　said　the　doctor；　when　the　other　had　brokenly　described　all　that　he　had　dared　to　examine。　〃It　is　fortunate　that　he　is　here〃；　and　even　as　he　spoke　the　great　detective　entered　the　study；　attracted　by　the　cry。　　It　was　almost　amusing　to　note　his　typical　transformation；　he　had　come　with　the　common　concern　of　a　host　and　a　gentleman；　fearing　that　some　guest　or　servant　was　ill。　　When　he　was　told　the　gory　fact；　he　turned　with　all　his　gravity　instantly　bright　and　businesslike；　for　this；　however　abrupt　and　awful；　was　his　business。　　　　　〃Strange；　gentlemen；〃　he　said　as　they　hurried　out　into　the　garden；　〃that　I　should　have　hunted　mysteries　all　over　the　earth；　and　now　one　comes　and　settles　in　my　own　back…yard。　　But　where　is　the　place？〃　　They　crossed　the　lawn　less　easily；　as　a　slight　mist　had　begun　to　rise　from　the　river；　but　under　the　guidance　of　the　shaken　Galloway　they　found　the　body　sunken　in　deep　grassthe　body　of　a　very　tall　and　broad…shouldered　man。　　He　lay　face　downwards；　so　they　could　only　see　that　his　big　shoulders　were　clad　in　black　cloth；　and　that　his　big　head　was　bald；　except　for　a　wisp　or　two　of　brown　hair　that　clung　to　his　skull　like　wet　seaweed。　　A　scarlet　serpent　of　blood　crawled　from　under　his　fallen　face。　　　　　〃At　least；〃　said　Simon；　with　a　deep　and　singular　intonation；　〃he　is　none　of　our　party。〃　　　　　〃Examine　him；　doctor；〃　cried　Valentin　rather　sharply。　　〃He　may　not　be　dead。〃　　　　　The　doctor　bent　down。　　〃He　is　not　quite　cold；　but　I　am　afraid　he　is　dead　enough；〃　he　answered。　　〃Just　help　me　to　lift　him　up。〃　　　　　They　lifted　him　carefully　an　inch　from　the　ground；　and　all　doubts　as　to　his　being　really　dead　were　settled　at　once　and　frightfully。　　The　head　fell　away。　　It　had　been　entirely　sundered　from　the　body；　whoever　had　cut　his　throat　had　managed　to　sever　the　neck　as　well。　　Even　Valentin　was　slightly　shocked。　　〃He　must　have　been　as　strong　as　a　gorilla；〃　he　muttered。　　　　　Not　without　a　shiver；　though　he　was　used　to　anatomical　abortions；　Dr。　Simon　lifted　the　head。　　It　was　slightly　slashed　about　the　neck　and　jaw；　but　the　face　was　substantially　unhurt。　　It　was　a　ponderous；　yellow　face；　at　once　sunken　and　swollen；　with　a　hawk…like　nose　and　heavy　lidsa　face　of　a　wicked　Roman　emperor；　with；　perhaps；　a　distant　touch　of　a　Chinese　emperor。　　All　p