"I do not mind your asking me; but I cannot tell you.

What passed between me and him----" She stopped; she was on delicate ground; this man, with his worldly experience, his acute intelligence, might lead her on to disclose what had happened that night; she could not cope with him.

"I do not know his name." The Marquess bowed his head, and smiled slightly, as if he scented the aroma of a commonplace romance.
"Quite so," he said.

"A casual meeting.

Such occurs occasionally in the course of one's life, and I dare say the resemblance you noticed was only a fancied one.