tention to him and walked straight to the chemist.
"Monsieur Fortin," I said, "do you know much about hydrocarbons?"
"They are my specialty," he said astonished.
"Have you ever heard of such a thing as cythyl?"
"Schweineri's cythyl? Oh, yes! We use it in perfumery."
"Good!" I said. "Has it an odour?"
"No—and, yes. One is always aware of its presence, but really nobody can affirm it has an odour. It is curious," he continued, looking at me, "it is very curious you should have asked me that, for all day I have been imagining I detected the presence of cythyl."
"Do you imagine so now?" I asked.
"Yes, more than ever."
I sprang to the front door and tossed out the butterfly. The splendid creature beat the air for a moment, flitted uncertainly hither and thither, and then, to my astonishment, sailed majestically back into the café and alighted on the hearthstone. For a moment I was nonplussed, but when my eyes rested on the Purple Emperor I comprehended in a flash.
"Lift that hearthstone!" I cried to the Brigadier Durand; "pry it up with your scabbard!"
