One could never tell.
"Matter of fact," went on Ronicky smoothly, lighting a tailor-made cigarette, while his companion rolled one of his own making, "we are looking for a lady who was on one of your trains.

We think you may possibly remember her.

Here's the picture." And, as he passed the snapshot to the Pullman conductor, he went on with the details of the date and the number of the train.
Robert Macklin in the meantime studied the picture carefully.

He had a keen eye for faces, but when it came to pretty faces his memory was a veritable lion.

He had talked a few moments with this very girl, and she had smiled at him.