"Oh, do let me!" she begged. "It is such a joy for your Granny. And be sure you knock on the wall if you want anything in the night. My bed is just on the other side, and the partition is quite thin. Just give a knock now, as soon as you are ready, so that we shall know where we are." And, sure enough, that evening I gave three knocks--a signal which, the week after, when I was ill, I repeated every morning for several days, because my grandmother wanted me to have some milk early. Then, when I thought that I could hear her stirring, so that she should not be kept waiting but might, the moment she had brought me the milk, go to sleep again, I ventured on three little taps, timidly, faintly, but for all that distinctly, for if I was afraid of disturbing her, supposing that I had been mistaken and that she was still asleep, I should not have wished her either to lie awake listening for a summons which she had not at once caught and which I should not have the courage to repeat. And scarcely had I given my taps than I heard three others, in a different intonation from mine, stamped with a calm authority, repeated twice over so that there should be no mistake, and saying to me plainly: "Don't get excited; I heard you; I shall be with you in a minute!" and shortly afterwards my grandmother appeared. I explained to her that I had been afraid that she would not hear me, or might think that it was some one in the room beyond who was tapping; at which she smiled: "Mistake my poor chick's knocking for anyone else! Why, Granny could tell it among a thousand! Do you suppose there's anyone else in the world who's such a silly-billy, with such feverish little knuckles, so afraid of waking me up and of not making me understand? Even if he just gave the least scratch, Granny could tell her mouse's sound at once, especially such a poor miserable little mouse as mine is. I could hear it just now, trying to make up its mind, and rustling the bedclothes, and going through all its tricks."