though he had played truant so often, he knew one or two things that perhaps you don't know, though you have always been so good and gone to school regularly. for instance, he knew that a drakling is a dragon's baby, and he felt sure that what he had to do was to find the third of the three noises that people used to hear coming from the mountains. of course, the clucking had been the cockatrice, and the big noise like a large gentleman asleep after dinner had been the big dragon. so the smaller rumbling must have been the drakling.