But memory training is important too; and an index is the best thing in the world for that. Take some subject you're studying in school--mountains, for example--they're always studying such big things as mountains, the work of rivers, and so on; or if they aren't to-day they will be tomorrow. Look at the references _as questions to yourself_ and see how well you can answer them: "How do mountains help make water-gates for the rivers?" and "Why do they have earthquakes in regions where mountains haven't got done with their growing?" Then you can have a lot of fun with these questions at home and with boy friends, after you have read the book together. For instance: Just how _did_ the pebbles help dig the Grand Canyon? And that's a poser for many grown people too--people who've travelled and met the Grand Canyon face to face! Try it on Father. Yes, and Teacher too. There are none of her boys that a teacher is so proud of as the boys that have initiative--_go-aheaditiveness_--and can _ask_ good questions as well as answer them. But, best of all, you can find no end of things to write about for your language work in school and for the little books of your own that I've already suggested in the H. & S. Take the subject of pebbles, for example. Although this whole book has to do with the life and adventures of pebbles, I haven't put the facts together in just the way _you_ will if you follow out the references under the heading "Pebbles" in this index. If you don't happen to remember how pebbles act as bankers for the farmers, how they helped make the Great Lakes, built the Grand Canyon, and so on, look these things up and then, as they thus become digested in your mind, write about them in your own way--the way you'd talk if you were telling somebody about it. Do that and you'll _have_ something! one of those things that mothers show to the neighbors, and that teachers show to visitors. Of course you'll have to have a name for your story and you'll think of plenty: "What One of My Pebbles Told Me," "The Pebbles in the World's Work," "What a Wonderful Thing a Pebble Is!" "Why Common Pebbles are Worth More than Diamonds"; for of course a diamond is a kind of pebble. GETTING ACQUAINTED WITH YOURSELF In all this you will not only find you'll have a good time, but, let me tell you, you'll be getting the best part of your education; you'll be getting acquainted with yourself, your undeveloped powers of memory--reasoning--expression. You'll find before you get so very old that one of the most important elements of success, of doing _your_ part in the world's great work of making itself better all the time, is in _having something worth while to say and being able to say it_. This was the making of the Greeks; and the Greeks, you know, were the most wonderful people that ever were. It all started with old "Know Thyself" Thales of Miletus. That's what did it! INDEX