The first question to be solved was the location of this hollow. What communication did it have with the surrounding region? Could one only depart from it by a flying-machine? And in what part of the United States were we? Was it not reasonable to estimate, that our flight through the darkness had covered several hundred leagues? There was one very natural hypothesis which deserved to be considered, if not actually accepted. What more natural harbor could there be for the “Terror” than the Great Eyrie? Was it too difficult a flight for our aviator to reach the summit? Could he not soar anywhere that the vultures and the eagles could? Did not that inaccessible Eyrie offer to the Master of the World just such a retreat as our police had been unable to discover, one in which he might well believe himself safe from all attacks? Moreover, the distance between Niagara Falls and this part of the Blueridge Mountains, did not exceed four hundred and fifty miles, a flight which would have been easy for the “Terror.” Yes, this idea more and more took possession of me. It crowded out a hundred other unsupported suggestions. Did not this explain the nature of the bond which existed between the Great Eyrie and the letter which I had received with our commander’s initials? And the threats against me if I renewed the ascent! And the espionage to which I had been subjected! And all the phenomena of which the Great Eyrie had been the theater, were they not to be attributed to this same cause—though what lay behind the phenomena was not yet clear? Yes, the Great Eyrie! The Great Eyrie! But since it had been impossible for me to penetrate here, would it not be equally impossible for me to get out again, except upon the “Terror?” Ah, if the mists would but lift! Perhaps I should recognize the place. What was as yet a mere hypothesis, would become a starting point to act upon. However, since I had freedom to move about, since neither the captain nor his men paid any heed to me, I resolved to explore the hollow. The three of them were all in the grotto toward the north end of the oval. Therefore I would commence my inspection at the southern end. Reaching the rocky wall, I skirted along its base and found it broken by many crevices; above, arose more solid rocks of that feldspar of which the chain of the Alleghanies largely consists. To what height the rock wall rose, or what was the character of its summit, was still impossible to see. I must wait until the sun had scattered the mists. In the meantime, I continued to follow along the base of the cliff. None of its cavities seemed to extend inward to any distance. Several of them contained debris from the hand of man, bits of broken wood, heaps of dried grasses. On the ground were still to be seen the footprints that the captain and his men must have left, perhaps months before, upon the sand.