A clap of wind blew away the reply, if there was any. This time the wind rose steadily. They waited another quarter of an hour, the gale blowing without pause. “This is profitless,” said Professor Eavenden, at length. “We had best go home.” Thankful for the respite, the younger man rose from the little depression where he had crouched for shelter from the wind. With a thrill of surprised delight, he realised that he was healthily sleepy. The quick, hard walk, the unwonted exercise, and the soft, fresh sweetness of the air, had produced an anodyne effect. But was the air so sweet? Colton turned and sniffed up wind. “Do you smell anything peculiar?” he asked his companion. “Unfortunately I am troubled with a catarrh which deadens my sense of smell,” replied the scientist. “There’s a peculiar reek in the air. I caught it with that last shift of wind. It’s like something I’ve come across before. There!” “Can you not describe it?” “Why, it’s—it’s a sickish, acid sort of odour,” said Colton hesitantly. “Where have I—— Oh, well, it’s probably a dead animal up to windward.” As they reached the house, he turned to the other. “What was it you thought you saw?” he asked bluntly. “What are you looking for?” “I am not satisfied that I saw anything,” answered Professor Ravenden evasively. “Imagination is a powerful factor, when the eye must accomplish its search in the instantaneous revelation of a lightning flash. As for what I am seeking, you heard as much as I. I thank you for your help, and, if you will pardon me, I will bid you good-night here, as I wish to make a few notes before retiring.” Leaving the professor busied by candle light at the desk in the main room, Dick Colton cautiously tiptoed up the stairs. At the top he stopped dead. From an open door at the end of the hall issued a shaft of light. In the soft glow stood a girl. Her face was toward Colton. Her eyes met his, but un-seeingly, for he was in the shadow, and her vision was dazzled by the light she had just made. Her face was softly flushed with sleep and her dark eyes were liquid under the heavy lids. She was dressed in some filmy, fluffy