"I let myself down to the ledge, and found that it was impossible to sit on it, except in one particular position. This fact confirmed my preconceived idea, and I proceeded to use the glass. Of course, 'forty-one degrees and thirteen minutes' could refer to nothing but the level above the visible horizon, since the horizontal direction was clearly indicated by the words, 'northeast and by north'. By means of a compass, I at once established this latter direction; then, pointing the telescope at an angle of forty-one degrees as best I could by estimate, I moved it cautiously up and down, until my attention was drawn to a circular opening in the foliage of a large tree in the distance. In the centre of this opening, I saw a white spot, but could not distinguish what it was. Adjusting the focus of the telescope, I looked again, and discerned it to be a human skull.

   "Upon this discovery, I was so hopeful to consider the mystery solved. The phrase, 'main branch, seventh limb, east side' could refer only to the position of the skull on the tree, while 'shoot from the left eye of the death's head' meant to shoot, or drop something, from the left eye of the skull; and that a 'beeline' (or a straight line), drawn from the nearest point of the tree through where 'the shot' fell, would extend a distance of fifty feet. Beneath that point, I thought it possible that a treasure lay hidden."

   "All this," I said, "is exceedingly clear; and, although ingenious, still simple and explicit. When you left the Bishop's Hotel, what then?"

   "Why, having carefully taken the bearings of the tree, I turned homewards. The instant I left 'the devil's seat', however, the circular opening vanished––nor could I get a glimpse of it afterwards. What seems to me the chief ingenuity in this whole business, is the fact that the circular opening is visible from no other point of view than the narrow ledge on the face of the rock.

   "In this journey to the 'Bishop's Hotel', I had been attended by Jupiter. He had no doubt observed my abstraction for some weeks, and took special care not to leave me alone. But, as I got up very early the next day, I gave him the slip and went alone into the hills, in search of the tree. After much effort, I found it. When I came home that night, my servant proposed to give me a whipping. The rest of the adventure, I believe you know it as well as I do myself."

   "I suppose you missed the spot in the first digging," I said, "through Jupiter's stupidity in letting the bug fall through the right eye of the skull, instead of through the left."

   "Precisely. That mistake made a difference of about two and a half inches in 'the shot'––that is to say, in the position of the stick nearest the tree. Had the treasure been beneath the 'shot', the error would have been of little moment; but 'the shot', together with the nearest point of the tree, were only two points for the establishment of a line of direction. Of course the error, however small in the beginning, increased as we proceeded with the line; and, by the time we had gone fifty feet, threw us quite off the chase. If not for my strong belief that a treasure was buried somewhere there, we might have had all our labor in vain."

   "But your grandiloquence, and the way you swung the bug––how excessively odd! I was sure you were mad. And why did you insist on dropping the bug, instead of a bullet, through the skull?"

   "Why, to be frank, I felt somewhat annoyed by your doubts regarding my sanity, and so decided to punish you quietly, in my own way, with a little bit of sober mystification. For this reason, I swung the beetle, and for this reason, I dropped it from the tree. Your observation of its great weight suggested the latter idea."

   "Yes, I see. And now there is only one thing which puzzles me––how do you explain the skeletons found in the hole?"

   "This is a question I can no better answer than yourself. There seems, however, only one plausible way of explaining them, though it is terrible to believe in such atrocity. It is clear that Kidd––if Kidd had indeed buried this treasure––it is clear that he must have had assistance in the labor. Then, when the work was done, perhaps he thought it better to remove all participants in his secret. Two blows, while his men were busy in the pit, may have been sufficient; or perhaps it required more––who can tell?"

                                                      THE END