Herman Cyril Mcneile 
Bull-Dog Drummond [EPUB ebook] 

In the month of December 1918, and on the very day that a British Cavalry Division marched into Cologne, with flags flying and bands playing as the conquerors of a beaten nation, the manager of the Hotel Nationale in Berne received a letter. Its contents appeared to puzzle him somewhat, for having read it twice he rang the bell on his desk to summon his secretary. Almost immediately the door opened, and a young French girl came into the room.