"Quickly recocking his pistol, Kaldhein raised it again. I involuntarily shrank back, expecting death; but before he could fire his arm suddenly dropped, and the pistol was discharged into the ground. Then began a strange scene. The man shouted, kicked, and beat up and down with his arms; his pistol fell from his hand, he sprang from side to side, he turned around, he struggled and yelled. "I stood astounded. For an instant I supposed the man had been overtaken by some sort of fit; but in a flash the truth came to me,--Kaldhein was being attacked by my protector, the invisible dog. "Horrified by this conviction, my first impulse was to save the man; and, without knowing what I was going to do, I stepped quickly toward him, but stumbling over something I did not see I fell sprawling. Before I could regain my feet I saw Kaldhein fall backward to the ground, where a scene took place, so terrible that I shall not attempt to describe it. When, with trembling steps, I approached, the man was dead. The invisible dog had almost torn him to pieces. "I could do nothing. I did not remain upon the spot another minute, but hurried home to the castle. As I rapidly walked on I felt the dog beside me, and, putting my hand upon him, I felt that he was panting terribly. For three days I did not leave the house. "About the end of this time I was sitting in an upper room of the castle, reflecting upon the recent dreadful event, when the thought struck me that the invisible dog, who was by my side, apparently asleep, must be of an unusually powerful build to overcome so easily such a strong man as Kaldhein. I felt a desire to know how large the creature really was, and, as I had never touched any portion of his body back of his shoulders, I now passed my hand along his back. I was amazed at his length, and when I had moved my hand at least seven feet from his head it still rested upon his body. And then the form of that body began to change in a manner which terrified me; but impelled by a horrible but irresistible curiosity, my hand moved on. "But I no longer touched the body of a dog; the form beneath my hand was cylindrical, apparently about a foot in diameter. As my hand moved on the diameter diminished, and the skin of the creature became cold and clammy. I was feeling the body of a snake! "I now had reached the open door of the room. The body of the snake extended through it. It went on to the top of the stairs; these I began to descend, my heart beating fast with terror, my face blanched, I am sure, but my hand still moving along the body of the awful creature. I had studied zoology, giving a good deal of attention to reptiles, and I knew that, judged by the ordinary ratio of diminution of the bodies of serpents, this one must extend a long distance down the stairs.