Of course it depended on how many teeth a mammoth had, but the number of a boy’s teeth might be some guide, and David, in the throes of grinding out the weekly letter to his father, passed his tongue round his own teeth, trying to count them by the sensory quality of it. But, losing count, he put an inky forefinger into his mouth instead. There seemed to be fourteen in his lower jaw and thirteen and a half in the upper, for half of a front tooth had been missing ever since, a few weeks ago, he had fallen out of a tree on to his face, and the most industrious scrutiny of that fatal spot had never resulted in his finding it. In any case, then, he had twenty-seven and a half teeth, and it was reasonable to suppose that a mammoth, therefore, unless he had fallen out of a tree (if there were such in the glacial age) had at least twenty-eight. That huge yellow lump of a thing, then, as big as David’s whole head, was only one twenty-eighth of his chewing apparatus. Why, an entire bun could stick to it and be unobserved. A mammoth could have twenty-eight buns in his mouth and really remain unaware of the fact. Fancy having a bun on every tooth and not knowing! How much ought a mammoth’s pocket-money to be if you had to provide on this scale? And when would its mouth be really full? And how . . . David was growing a little sleepy. “Blaize!” said Mr. Dutton’s voice. David sucked his finger. “Yes, sir!” he said. “Have you finished your letter home?” “No, sir,” said David, with engaging candour. “Then I would suggest that you ceased trying to clean your finger and get on with it.” “Rather, sir!” said David.