I was not long about this business. I soon perceived that the back of the empty space was closed in by a large box, and a similar one blocked up the right side. The left was the diagonal edge of the case itself, about twenty inches or two feet in width. But I troubled myself very little either about back, left, or right. It was the ceiling of the little chamber that had the greatest interest for me; for it was in that direction I intended, _if possible_, to continue my tunnel. I knew that I was now far enough in the horizontal direction; for the chief advantage I had gained by the discovery of the empty space was, that it carried me the thickness of the piano-case--about two feet, as I have said--in this course, besides the distance that was open, upwards. Neither forward, then, nor to the right or left, did I wish to go, unless forced to do so by an obstacle. Upward was the echo of my thoughts. _Excelsior_! _excelsior_! Two or three stages more--perhaps less, if no obstacle intervened--and I might be free. My heart beat joyfully as the prospect passed before my mind. It was not without a keen anxiety that I raised my hand to the ceiling of the empty chamber. My fingers trembled as they touched what I well knew to be canvas, and involuntarily they recoiled from it. O, mercy!-- once more that hated fabric--a bale of linen! I was not so sure of this however. I remembered the mistake I had already made in this regard. I must examine farther. I closed my fist, and gave the bottom of the package a smart rap with my knuckles. Ha! it was a pleasant sound that answered to the blow. It was not a bale of linen, then, but a box, covered, like many others, with several folds of coarse cheap canvas. It could not be cloth, either; for instead of the dull report which the cloth-boxes give out when struck, the one in question returned a hollow sound, precisely that of one that was empty! This appeared strange enough. It could not be empty, else why was it there? and yet if not empty, what did it contain? I hammered upon it with the haft of my knife--still the same hollow sound! "Good!" thought I. "If empty, all the better; but if not, surely there is something in it of a light nature--something that may be easily got rid of. Good!" After making this reflection, I resolved to waste no more time in conjectures, but to satisfy myself of the contents of this new box, by making my way into it; and in a trice I had ripped off the canvas that protected its bottom. I found the position in which I stood inconvenient. The triangular space, narrowing acutely towards the bottom, hindered me from standing fairly on my feet; but I soon remedied this defect, by filling the angle with some pieces of cloth and velvet that were near at hand. I then proceeded more comfortably with my work.