She turned toward me at last, deliberately, her fan against her lips, studying me.  And I did as much, taking such advantage as I could of the passing street lamps.  Then, all at once, without warning or apology, she smiled, showing very even and white teeth.

She smiled.  There came to me from the purple-colored shadows some sort of deep perfume, strange to me.  I frown at the description of such things and such emotions, but I swear that as I sat there, a stranger, not four minutes in companionship with this other stranger, I felt swim up around me some sort of amber shadow, edged with purple—­the shadow, as I figured it then, being this perfume, curious and alluring!

It was wet, there in the street.  Why should I rebel at this stealing charm of color or fragrance—­let those name it better who can.  At least I sat, smiling to myself in my purple-amber shadow, now in no very special hurry.  And now again she smiled, thoughtfully, rather approving my own silence, as I guessed; perhaps because it showed no unmanly perturbation—­my lack of imagination passing for aplomb.

At last I could not, in politeness, keep this up further.

“How may I serve the Baroness?” said I.

She started back on the seat as far as she could go.

“How did you know?” she asked.  “And who are you?”

I laughed.  “I did not know, and did not guess until almost as I began to speak; but if it comes to that, I might say I am simply an humble gentleman of Washington here.  I might be privileged to peep in at ambassadors’ balls—­through the windows, at least.”

“But you were not there—­you did not see me?  I never saw you in my life until this very moment—­how, then, do you know me?  Speak!  At once!” Her satins rustled.  I knew she was tapping a foot on the carriage floor.

“Madam,” I answered, laughing at her; “by this amber purple shadow, with flecks of scarlet and pink; by this perfume which weaves webs for me here in this carriage, I know you.  The light is poor, but it is good enough to show one who can be no one else but the Baroness von Ritz.”

I was in the mood to spice an adventure which had gone thus far.  Of course she thought me crazed, and drew back again in the shadow; but when I turned and smiled, she smiled in answer—­herself somewhat puzzled.

“The Baroness von Ritz can not be disguised,” I said; “not even if she wore her domino.”

She looked down at the little mask which hung from the silken cord, and flung it from her.

“Oh, then, very well!” she said.  “If you know who I am, who are you, and why do you talk in this absurd way with me, a stranger?”

“And why, Madam, do you take me up, a stranger, in this absurd way, at midnight, on the streets of Washington?—­I, who am engaged on business for my chief?”

She tapped again with her foot on the carriage floor.  “Tell me who you are!” she said.