As soon as tide turned the anchor was hove up and the _Susan_ got under way again. The boys soon learnt the meaning of the word beating, and found that it meant sailing backwards and forwards across the channel, with the wind sometimes on one side of the boat and sometimes on the other. Geoffrey wanted very much to learn why, when the wind was so nearly ahead, the boat advanced instead of drifting backwards or sideways. But this was altogether beyond the power of either Master Lirriper or Joe Chambers to explain. They said every one knew that when the sails were full a vessel went in the direction in which her head pointed. "It's just the same way with yourself, Master Geoffrey. You see, when you look one way that's the way you go. When you turn your head and point another way, of course you go off that way; and it's just the same thing with the ship." "I don't think it's the same thing, Master Lirriper," Geoffrey said puzzled. "In one case the power that makes one go comes from the inside, and so one can go in any direction one likes; in the other it comes from outside, and you would think the ship would have to go any way the wind pushes her. If you stand up and I give you a push, I push you straight away from me. You don't go sideways or come forward in the direction of my shoulder, which is what the ship does." John Lirriper took off his cap and scratched his head. "I suppose it is as you say, Master Geoffrey, though I never thought of it before. There is some reason, no doubt, why the craft moves up against the wind so long as the sails are full, instead of drifting away to leeward; though I never heard tell of it, and never heard anyone ask before. I daresay a learned man could tell why it is; and if you ask your good father when you go back I would wager he can explain it. It always seems to me as if a boat have got some sort of sense, just like a human being or a horse, and when she knows which way you wants her to go she goes. That's how it seems to me--ain't it, Joe?" "Something like that, uncle. Every one knows that a boat's got her humours, and sometimes she sails better than she does others; and each boat's got her own fancies. Some does their best when they are beating, and some are lively in a heavy sea, and seem as if they enjoy it; and others get sulky, and don't seem to take the trouble to lift their bows up when a wave meets them; and they groans and complains if the wind is too hard for them, just like a human being. When you goes to a new vessel you have got to learn her tricks and her ways and what she will do, and what she won't do, and just to humour her as you would a child, I don't say as I think she is actually alive; but every sailor will tell you that there is something about her that her builders never put there."