They stood upon the roof of a London boarding-house in the neighborhood of Russell Square-one of those grim shelters, the refuge of Transatlantic curiosity and British penury. The girl-she represented the former race was leaning against the frail palisading, with gloomy expression and eyes set as though in fixed contemplation of the uninspiring panorama. The young man-unmistakably, uncompromisingly English-stood with his back to the chimney a few feet away, watching his companion. The silence between them was as yet unbroken, had lasted, indeed, since she had stolen away from the shabby drawing-room below, where a florid lady with a raucous voice had been shouting a music-hall ditty. Close upon her heels, but without speech of any sort, he had followed. They were almost strangers, except for the occasional word or two of greeting which the etiquette of the establishment demanded. Yet she had accepted his espionage without any protest of word or look. He had followed her with a very definite object. Had she surmised it, he wondered? She had not turned her head or vouchsafed even a single question or remark to him since he had pushed his way through the trap-door almost at her heels and stepped out on to the leads. Yet it seemed to him that she must guess.