And yet, approaching the truth as I felt myself to be, I had a deep-down feeling that at the same time I was wrong. Carefully I begun to examine the objections to my suddenly-formed theory, and instantly I was impressed by them. In the first place, take an inch board with a five-eighths hole in it, peep through, and see how much, or rather how little, of a field of vision your eye commands. Next, consider the awkwardness of peering through that hole, not in a vertical wall or door, but in horizontal planking some feet above your head. Then, most important of all, weigh the extreme unlikeliness of it that Esdaile, who had merely gone down for a bottle of wine and had no reason whatever to dream that calamity was imminent, should have had his eye at that hole at that particular moment of time. It was preposterous. All had happened so quickly. He would have had to stand on something, probably to pile up furniture; even with a pair of household steps ready in position he would have had to mount them—nay, he would first have had to think of mounting them. I had no means of telling if he had previously known of that hole in his floor, but say that he had: does one, on hearing an unaccountable noise, instantly run over in one's mind every chink and cranny of one's dwelling and select one of them as an observation-post? He could have dashed upstairs again and seen for himself what was the matter in half the time.

No; in the very moment when I thought I had got it, it eluded me again. Those perfectly ordinary considerations, of time, position and common sense, seemed to dispose of my notion completely. Or almost completely. There remained the hole. My conviction that the hole, in one way or another, had something to do with it was shaken, but not destroyed. And, as I was denied access to the cellar, I rose from the chair in order to make a further examination of the studio.

And again, though the roof-plane was no longer there, I seemed to see that circular hole in the middle of its cracked star. I remembered, too, Esdaile's assumption that it was a bullet-hole and his search "high and low" for the bullet that had made it. But was it necessarily a bullet-hole at all? Bullets are not the only things that make holes. When a heavyish mass like two falling men hits something else en plein fouet, can every neighboring scratch or fracture be assigned its proper cause? There was no getting away from the fact that the bullet had been found elsewhere. Might not some object have fallen from a pocket? Or some portion of the plane itself have dropped off? With the pane replaced it seemed useless to speculate.

Nor did my further explorations add much to my knowledge. They consisted of estimating distances and relative positions of things, in an endeavor to arrive at the physical significance of that hole in the floor. It was no longer in the studio at all that I was interested; all my thoughts were in that locked chamber below. I felt as annoyed as Monty himself had been at all this juggling with the key. But I hardly felt myself at liberty to break my friend's doors.

Nor—this too presently occurred to me—was I quite sure what I ought to do with that ring. Merely to put it back where I had found it seemed rather crass, and whether it should be returned to Rooke or to Mrs. Cunningham herself was a niceish sort of point. I ended by putting it into my waistcoat pocket.