Polishing the glasses he took another sharp look.
He leaned across the aisle.
"I _beg_ your pardon," he said, with stately courtesy.

"But I am sure I have met you somewhere.

No, don't tell me.

Pardon an old man's harmless vanity, but it is my weakness to make my memory do its work unaided, when possible.

I have a famous memory generally, and yours is not a face to be easily forgotten.