It was not long before Harry could sail the boat nicely, and the others, by attending closely to Uncle John's lessons, learned almost as much as their young captain. So far as boat-sailing can be taught in fair weather, Harry was carefully and thoroughly taught in six or seven lessons, and could handle the Whitewing beautifully; but the ability to judge of the weather, to tell when it is going to blow, and how the wind will probably shift, can of course be learned only by actual experience.