By some unfortunate accident, there were neither blinds nor curtains to the windows of the Professor’s room. The previous night he had thought little of this, but tonight there seemed every prospect of a bright moon rising to shine directly on his bed, and probably wake him later on. When he noticed this he was a good deal annoyed, but, with an ingenuity which I can only envy, he succeeded in rigging up, with the help of a railway-rug, some safety-pins, and a stick and umbrella, a screen which, if it only held together, would completely keep the moonlight off his bed. And shortly afterwards he was comfortably in that bed. When he had read a somewhat solid work long enough to produce a decided wish for sleep, he cast a drowsy glance round the room, blew out the candle, and fell back upon the pillow. He must have slept soundly for an hour or more, when a sudden clatter shook him up in a most unwelcome manner. In a moment he realized what had happened: his carefully-constructed screen had given way, and a very bright frosty moon was shining directly on his face. This was highly annoying. Could he possibly get up and reconstruct the screen? or could he manage to sleep if he did not? For some minutes he lay and pondered over the possibilities; then he turned over sharply, and with his eyes open lay breathlessly listening. There had been a movement, he was sure, in the empty bed on the opposite side of the room. Tomorrow he would have it moved, for there must be rats or something playing about in it. It was quiet now. No! the commotion began again. There was a rustling and shaking: surely more than any rat could cause.