The Five Knots by Fred M. White

"But you couldn't identify it," Wilfrid said, speaking as coolly as he could. "You don't mean to tell me that it was the same hand? You couldn't swear to it?"

"Perhaps not," Beatrice admitted. "But to all practical purposes it was the same hand though the arm was hidden in a black sleeve and the whitest of cuffs. But you can imagine how the incident disturbed me. I pressed forward as eagerly as I could, but at that moment somebody had finished singing on the stage and there was a rush of men into the refreshment-room, so that I was prevented from pursuing my investigations. But I am frightened, Wilfrid. The thing seems to have taken my courage out of me. I wish you would try to find out if there is a man here like the one I have described."