Powers of Darkness by Fred M. White

Joe Copping spoke from the bottom of his heart. It was exactly as Alice had anticipated.

"There is no occasion to go quite so far as that," she said, with a smile. "What you want is a hundred pounds. Mary must have a sea voyage without delay, and she must not return here. You will also get employment elsewhere, which will not be so difficult as it seems. We will play a game that we all used to be fond of as children--we will play 'Supposing.' Now suppose I ask you to do something for me. It isn't much that I am going to suggest. All I ask you to do is to be blind for a day or two, a week at the outside. We will take it that you have not a good memory for faces--men who are clean-shaven and dressed in that hideous convict garb are very like each other."