But nothing would do; for he screamed and cried all day for a water-baby, to come and drive away the monsters; and of course they did not try to find one, because they did not believe in them, and were thinking of nothing but Bumpsterhausen's blue follicles; having, as usual, set the cart before the horse, and taken the effect for the cause. So they were forced at last to let the poor professor ease his mind by writing a great book, exactly contrary to all his old opinions; in which he proved that the moon was made of green cheese, and that all the mites in it (which you may see sometimes quite plain through a telescope, if you will only keep the lens dirty enough, as Mr. Weekes kept his voltaic battery) are nothing in the world but little babies, who are hatching and swarming up there in millions, ready to come down into this world whenever children want a new little brother or sister. Which must be a mistake, for this one reason: that, there being no atmosphere round the moon (though some one or other says there is, at least on the other side, and that he has been round at the back of it to see, and found that the moon was just the shape of a Bath bun, and so wet that the man in the moon went about on Midsummer-day in Macintoshes and Cording's boots, spearing eels and sneezing); that, therefore, I say, there being no atmosphere, there can be no evaporation; and therefore, the dew-point can never fall below 71.5° below zero of Fahrenheit: and, therefore, it cannot be cold enough there about four o'clock in the morning to condense the babies' mesenteric apophthegms into their left ventricles; and, therefore, they can never catch the hooping-cough; and if they do not have hooping-cough, they cannot be babies at all; and, therefore, there are no babies in the moon.--Q.E.D. Which may seem a roundabout reason; and so, perhaps, it is: but you will have heard worse ones in your time, and from better men than you are. But one thing is certain; that, when the good old doctor got his book written, he felt considerably relieved from Bumpsterhausen's blue follicles, and a few things infinitely worse; to wit, from pride and vain-glory, and from blindness and hardness of heart; which are the true causes of Bumpsterhausen's blue follicles, and of a good many other ugly things besides. Whereon the foul flood-water in his brains ran down, and cleared to a fine coffee colour, such as fish like to rise in, till very fine clean fresh-run fish did begin to rise in his brains; and he caught two or three of them (which is exceedingly fine sport, for brain rivers), and anatomised them carefully, and never mentioned what he found out from them, except to little children; and became ever after a sadder and a wiser man; which is a very good thing to become, my dear little boy, even though one has to pay a heavy price for the blessing.