When we left him last he had just found on the floor of his host's private library one of the tiny paper pellets which he had dropped purposely from his pocket when blindfolded the previous night. The finding of this pellet he looked on as proof-positive that the entrance to the hiding-place of the Diamond must be in that room. His discovery was an important one. It was his first step towards that goal whither all his hopes and wishes now tended. It placed him at once on a certain vantage ground. Still he was puzzled by the consideration of what his second step ought to be. For some time he could not see his way at all. On the pretence of wanting some particular volume from its shelves he contrived once and again to visit the private library while Platzoff was engaged elsewhere. But he could not visit it without first asking permission, owing to the simple fact of its door being always kept locked. The required permission was grudgingly granted by Platzoff--he could see that, also that it would not be wise to court the privilege too often. Indeed, it was a privilege that proved of little or no service, either Cleon or Jasmin being sent with him to unlock and relock the door, and evidently having secret instructions not to leave the library so long as he was in it. While looking for the required volume he could merely take a few careless glances around, and such glances merely served to show him that the line of book-shelves was unbroken except by the two doorways and the fireplace. He had not, indeed, been sanguine enough to expect that such a casual examination would reveal to him the secret entrance that led to the cavern. But he had half hoped that by some faint sign, by some insignificant token, which to those not in the secret would seem utterly meaningless, he might be able to seize on the first hint of the wished-for clue. But in so far he was doomed to disappointment. No sign nor token of the faintest kind was visible to his quick-searching eyes.