"Have you any idea?"
He waited a few seconds before replying:
"What puzzles me is this telescope hidden, dropped in that corner, at the last moment. I wonder what it was used for.... From the ground-floor windows you see nothing but the trees in the garden ... and the same, I expect, from all the windows.... We are in a valley, without the least open horizon.... To use the telescope, one would have to go up to the top of the house.... Shall we go up?"
She did not hesitate. The mystery surrounding the whole adventure excited her curiosity so keenly that she could think of nothing but accompanying Rénine and assisting him in his investigations.
They went upstairs accordingly, and, on the second floor, came to a landing where they found the spiral staircase leading to the belvedere.
At the top of this was a platform in the open air, but surrounded by a parapet over six feet high.
"There must have been battlements which have been filled in since," observed Prince Rénine. "Look here, there were loop-holes at one time. They may have been blocked."
"In any case," she said, "the telescope was of no use up here either and we may as well go down again."
"I don't agree," he said. "Logic tells us that there must have been some gap through which the country could be seen and this was the spot where the telescope was used."
He hoisted himself by his wrists to the top of the parapet and then saw that this point of vantage commanded the whole of the valley, including the park, with its tall trees marking the horizon; and, beyond, a depression in a wood surmounting a hill, at a distance of some seven or eight hundred yards, stood another tower, squat and in ruins, covered with ivy from top to bottom.