eleven o'clock precisely
May I speak to you a moment ? '' He was a short , thick-set , smooth-shaven , greasy man , dressed plainly in black , with a huge emerald pin in his shirt front . I have never had any particular use for a man with an emerald pin in his shirt front . `` There will be a game of baccarat , '' he continued in a low voice , his eyes glancing about furtively , `` at eleven o'clock precisely . Knock twice at this door . '' Old habitués of Lucerne -- habitués of years , men who never cross the Alps without at least a day 's stroll under the Noah 's - ark trees , -- will tell you over their coffee that since the opening of the St. Gotthard Tunnel this half-way house of Lucerne -- this oasis between Paris and Rome -- has sheltered most of the adventurers of Europe ; that under these same trees , and on these very benches , nihilists have sat and plotted , refugees and outlaws have talked in whispers , and adventuresses , with jeweled stilettos tucked in their bosoms , have lain in wait for fresher victims . I had never in my wanderings met any of these mysterious and delightful people .