It must have been about an hour before the dawn when we were terrified, beyond all description, by a crash against one of the windows of the _Sirius_, followed by a moan as of pain, so appalling, so unearthly, that our very blood seemed to curdle with horror. Even Doctor Hermann himself was visibly disconcerted. Perhaps it was owing to the highly wrought state of our nerves, but all of us, for the moment, were too terror-stricken to move. In the Doctor's case the alarm was only momentary, and with intrepid courage he rushed to the broken window, firing a couple of shots from his revolver at some dread shape struggling to enter the apartment. The Doctor was a poor hand with such a weapon; both bullets missed their mark; and before a third shot could be fired, the frightful creature had vanished. Moan after moan was heard; now near, then far away in the distance, sounding more like the voices of tortured souls, than of any material being. In a few moments, another of these mysterious creatures appeared, and this time we watched it approach with rapt astonishment, as it floated through the air in the full focus of the rays from our electric lamps. No creature of Earth possesses such means of locomotion. It looked like a huge dark ball, perhaps six feet in diameter; and as it came towards us, we noticed that it was revolving with enormous rapidity, forcing its way through the air, evidently on the same principle as a screw-propeller in the water. Graham had by this time regained his self-possession, and, with his rifle in hand, as this monster approached, he said: "Doctor, shall I fire?" "Yes, Graham, by all means; but be absolutely sure of your aim before doing so." Almost before the Doctor had finished speaking, the crack of Graham's rifle rang out; but the animal continued its course, and came with a crash against the _Sirius_. The shot had told, nevertheless, and we heard its body fall through the reeds, and drop with a heavy thud on the spongy ground. "Well done, Mr. Graham! A splendid shot! He's doon! He's doon!" sang out Sandy at the top of his voice, evidently both pleased and comforted beyond measure, to see that these strange beings we had come amongst were not proof against earthly powder and ball. CHAPTER VIII. A STRANGE WORLD.