This is a never-failing sport.

Indeed I am told there are some Clubs in the town where nobody ever speaks to anybody.

They sit in the coffee-room, quite silent, and watching each other.
Yet how little you can tell from a man's outward demeanour! There's a man at our Club--large, heavy, middle-aged--gorgeously dressed--rather bald--with lacquered boots--and a boa when he goes out; quiet in demeanour, always ordering and consuming a RECHERCHE little dinner: whom I have mistaken for Sir John Pocklington any time these five years, and respected as a man with five hundred pounds PER DIEM; and I find he is but a clerk in an office in the City, with not two hundred pounds income, and his name is Jubber.

Sir John Pocklington was, on the contrary, the dirty little snuffy man who cried out so about the bad quality of the beer, and grumbled at being overcharged three-halfpence for a herring, seated at the next table to Jubber on the day when some one pointed the Baronet out to me.
Take a different sort of mystery.

I see, for instance, old Fawney stealing round the rooms of the Club, with glassy, meaningless eyes, and an endless greasy simper--he fawns on everybody he meets, and shakes hands with you, and blesses you, and betrays the most tender and astonishing interest in your welfare.