"We drove up the hill toward the plateau at the top of the island, but as we passed through the village--Fortune's Well I think they call it--my father stopped the carriage at a tobacconist's, and went into the shop. He came out again with some plugs of tobacco--a good many--and got into the carriage. You won't guess why he bought them. I didn't." "Well?" said Chayne, and now he spoke with suspense. Suspense, too, was visible in his quiet attitude. There was a mystery which for Sylvia's sake he wished to unravel. Why did Gabriel Strood now call himself Garratt Skinner? That was the mystery. But he must unravel it without doing any hurt to Sylvia. He could not go too warily--of that he had been sure, ever since Kenyon had refused to speak of it. There might be some hidden thing which for Sylvia's sake must not be brought to light. Therefore he must find out the truth without help from any one. He wondered whether unconsciously Sylvia herself was going to give him the clue. Was she to tell him what she did not know herself--why Gabriel Strood was now Garratt Skinner? "Well?" he repeated. "As we continued up the hill," she resumed, "my father cut up the tobacco into small pieces with his pocket knife. 'Why are you doing that?' I asked, and he laughed and said, 'Wait, you will see.' At the top of the hill we got out of the carriage and walked across the open plateau. In front of us, rising high above a little village, stood out a hideous white building. My father asked if I knew what it was. I said I guessed." "It was the prison," Chayne interrupted, quickly. "Yes." "You went to it?" Upon the answer to the question depended whether or no Chayne was to unravel his mystery, to-day. "No," replied Sylvia, and Chayne drew a breath. Had she answered "Yes," the suspicion which had formed within his mind must needs be set aside, as clearly and finally disproved. Since she answered "No," the suspicion gathered strength. "We went, however, near to it. We went as close to it as the quarries. It was five o'clock in the afternoon, and as we came to the corner of the wall which surrounds the quarries, my father said, 'They have stopped work now.'" "He knew that?" asked Chayne. "Yes. We turned into a street which runs down toward the prison. On one side are small houses, on the other the long wall of the Government quarries. The street was empty; only now and then--very seldom--some one passed along it. On the top of the wall, there were sentry-boxes built at intervals, for the warders to overlook the convicts. But these were empty too. The wall is not high; I suppose--in fact my father said--the quarry was deep on the other side." "Yes," said Chayne, quietly. "And then?"