"That's half water, too; but it cannot hide every clew. You have eyes for the imperceptible; use them, Mr. Harper, use them." "I will; but this is a detective's work. Do not expect too much from me." "I expect nothing. I do not dare to. Let us tread very softly, that is all, and be careful to talk low, if we have anything to say." By this time they had rounded the corner of the house and entered a narrow walk, flagged with brick, which connected the space in front with the rear offices and garden. This walk ran close to the walls which were broken on this side by an ell projecting in the direction of the mill-stream. It was from the roof of this ell that Anitra declared Georgian to have slipped and fallen. Their first care was to glance up at the roof. It was a sloping one and Anitra's story seemed credible enough when they noted how much easier it would be to drop upon it from the little balcony overhead than to traverse the roof itself and reach the ground beneath without slipping. But as they looked longer, each face betrayed doubt. The descent from the balcony was easy enough, but how about the passage from Georgian's window to the balcony? This latter was confined to the one window, and was surrounded by an ornamental balustrade, high enough to offer a decided obstacle to the adventurous person endeavoring to leap upon it from the adjoining window-ledge. However, this leap, made in the dark and under circumstances inducing the utmost recklessness, might look practical enough from the window-ledge itself, and Mr. Harper, making a remark to this effect, proposed that they should examine the ground rather than the house for evidences of Mrs. Ransom's slip and fall as related by Anitra. The only spot where they could hope to find such was in the one short stretch--the width of the ell--underlying the edge of the sloping roof. But this spot was all flagged, as I have already said, and when their eyes strayed beyond it to the untilled fields, stretching between them and the great rock at the verge of the waterfall from which she was supposed to have taken her fatal leap, it was to find them as unproductive of evidence as the brick walk itself. Not one pair of feet but many had passed that way since early morning. The ground showed a mass of impressions of all sizes and shapes, amid which it would have been impossible for them, without the necessary experience, to have followed up the flight of any one person. They had come to their task too late. "Futile," decided the lawyer. "There is no use in our going that way." And he turned to look again at the ground in their immediate vicinity. As he did so, his eye lighted on the triangular spot where the ell met the side of the house under the kitchen windows. Here there was no flagging, the walk taking a diagonal course from the corner of the ell to the kitchen door.