Gerald, who was an expert with the punt-pole, was taking her up that pretty reach of the Thames which winds between Shepperton and Walton, with the long rows of poplars fringing the river bank. They had lunched at the little riverside inn at Halliford, and were now making their way slowly up-stream. Gerald, in flannels, with coat off and sleeves upturned, placing his pole and withdrawing it without any apparent effort. Since that adventurous night at Bridge Place they had become even closer friends. No day passed but they met. The previous two Sundays Durrant had spent with her, the first at Dorking, where they had wandered over Leith Hill and along the Surrey lanes, and the next Sunday at Brighton. This, the third Sunday, they had decided to spend together on the Thames. As they were passing beneath a long row of trees which overhung the water, the girl, who was in white, raised herself from her couch of cushions and suggested that they should tie up the punt there. "Certainly," he replied, and a few moments later he had secured the punt to a tree root, and, sitting down to rest, he lit his pipe. "Do you know, Gerald, I’ve been thinking again about Mr. Boyne," she said. "I can’t get the man out of my mind." "Well, to tell the truth, Marigold, neither can I," replied the young man. "Ever since that night at Hammersmith I’ve been trying in vain to solve the mystery." "About the person concealed upstairs," remarked the blue-eyed girl reflectively. "Yes, it’s most curious." "It’s more than curious," her companion declared. "Though I haven’t mentioned it to you, I’ve watched the house for several nights, but I must admit that I’ve seen nothing at all suspicious." "Oh! Then you’ve been on the watch!" she cried excitedly. "Yes, on four occasions, and all to no purpose. Last Friday I waited from nine o’clock till one in the morning, and got wet through. He returned about ten, but did not come out again." "He was upstairs with his secret friend, I suppose," said the girl. "No doubt. Whoever may be confined there could not exist without seeing a human face and conversing with him, even for five minutes each day, or he would certainly go mad," said Gerald. "You remember I said that Italians, who have abolished capital punishment for murder, have substituted solitary confinement. It is far more terrible. They confine the assassin in a cell in silence, without sight of a human face. Their food is placed upon a turntable which revolves into the cell, so that the prisoner never sees a face. Such torture was invented long ago in the Bastille, and in every case it drives the guilty one raving mad within five years." "How horrible!" cried the girl. "I admit it is, but surely the punishment is far greater than that of hanging, or even the guillotine. Both are instantaneous, yet in Italy the criminal suffers all the tortures of Dante’s Inferno—and deservedly so." "Then you saw nothing?" asked Marigold.