While we were busy making the trench to keep the rain from our hut, another notion came all of a sudden into my mind, which, in a kind of merry sport, I at once made known to Billy. "We will make a moat about our castle, Billy," said I. "What's a moat, and where's our castle?" says he, leaning on his spade, and looking all around. "Why, every Englishman's house is his castle, as they say," I answered, "and as to a moat, you must know, Billy, that in the olden times----" "The times of Robin Hood or Robinson Crusoe?" says he; "for if it is I don't believe a word of it." "This is quite true, I assure you," I said. "In the olden times, I say, when every great lord lived in his castle, there was a great ditch or trench all round it, to keep enemies away, for in those times lord often used to fight lord." "Like rats," says Billy. "Go on, master." "Well, that ditch was called a moat, and it could only be crossed by a drawbridge," I said, "that is, a bridge that was let down over it from the castle gateway; and so, when the bridge was up, and the moat filled with water, no enemy could get into the castle, and the people inside were safe." "And suppose they were," says Billy, "what's the good unless they'd got enough victuals inside to last 'em ever so long? If I was the lord outside I'd stop there till they either starved or came out and had a good fight." [Sidenote: Beginning a Moat] I answered that no doubt that was what they did, and went on to say that if we continued our trench and made it wider and deeper, bringing it close against the walls of our castle, we might add very greatly to the strength of our position if ever the savages came to the island and we had to defend ourselves against them. As to the matter of food, I said that we had in the cavern below the castle as good a storehouse as we could wish for, and I resolved that we would start at once, or at least as soon as we had finished our canoe, to convey a great store of bread-fruit and yams, and salted pork and fish, into the cavern, for which purpose we should have to increase the number of our pots and pans. But since this storehouse would be of little use to us if we were driven out of the castle, Billy consented to help me to dig a moat, though he said it would take us ten years to finish it, if we made it deep enough and wide enough to be of any avail. And, indeed, we were not long in finding out, when we began the work, that it would take us a very great time, if not ten years; for to be of any defensive use the moat must be at least six feet deep and about twice as wide, and we were aghast when, at the end of a day's work with our spades, we saw the exceeding smallness of what we had achieved. I was minded to give up the attempt, though it always vexed me to leave a thing half done, and the partial excavation we had made gave an untidy appearance to the place which displeased me mightily. Moreover, the rains