He opened the door of his laboratory and stepped into the hall. He saw nothing of Ned or Mr. Damon approaching and at once became aware of a peculiar odor. At first he could not account for it, thinking, for a moment, that his father might be at work in the chemical laboratory farther down the corridor. But after a second deep breath Tom knew it was no chemical he smelled. “It—it’s—fash!” he murmured. “The peculiar melon fruit that Koku was wishing for. But how in the world could that smell get here? There isn’t any fash within hundreds of miles—yes, even thousands! How Koku could get any——” He paused. There was a dark object on the floor near where the giant had been sitting on guard. Tom switched on a brilliant overhead light. It illuminated the place where Koku had been sitting, but the giant was no longer in his chair. He was sprawled on the floor, an inert lump of flesh, while, not far from him, was one of those peculiar melons, or fash fruits, of which the giants of that far-off, strange land were so fond. “Can I be dreaming?” gasped Tom. “How did this happen? Koku must be drugged! How did he get that fash? And what does it all mean?” As he started forward a noise behind him attracted his attention. CHAPTER XV A SINISTER WARNING LIKE an electrical flash it came into the mind of Tom Swift that there was something wrong here—something terribly and dangerously wrong. The drugged giant—nothing less than a drug could account for the helplessness of Koku—the appearance of that strange fruit, the noise behind—all these were warnings not to be ignored. So, though his first impulse was to hasten to the aid of the giant, when he heard that noise back of him Tom turned. He was only just in time. He had a glimpse of a figure gliding toward him out of the shadows, for that part of the corridor was not brightly lighted. And the figure was that of the man lately discharged—Greenbaum! With uplifted hand, in which was some sort of a weapon Tom could not distinguish, Greenbaum glided toward him. Tom was taken so by surprise and was so off his guard because of what had happened to Koku that he might have fallen a victim to Greenbaum. But at that moment occurred an interruption and a diversion that saved the situation, and perhaps Tom’s life. The door farther down the corridor opened and Mr. Damon and Ned, preceded by Eradicate, who had been serving as guard there, came out. The two performers, receiving no answer to their telephonic signal, had rightly concluded that Tom had finished experimenting for the night. “At the same time I thought something might be wrong when you didn’t answer,” Ned explained later.