But remember that in all these changes of scenery--in the crumplings and the foldings, and new rock deposits and the carving by the rivers and the frosts and the winds and the waves of the sea--we have certain similar materials, similarly arranged, stretching over vast areas, and the consequence is a certain uniformity and rhythm in the ups and downs of the landscape and in the changes worked in the walls of stone "where time and storm have set their wild signatures upon them." HIDE AND SEEK IN THE LIBRARY What would you think of seeing the leaves all out and the trees in bloom on Christmas Day? That happens right along, and the people who live in the lands where this occurs don't think anything of it, because this is in the Southern Hemisphere during the vacation season of the sea. One peculiar thing about this spring and summer in the winter time in Africa is that when the leaves first come out they are not green at all. They are brown, red, and pink. Later on they turn green--just as any well-behaved leaf is supposed to do.[50] It's as if they got mixed in their dates and thought at first it was autumn and then woke up and said: "Oh, yes, to be sure, this is spring! What are we thinking about?" [Footnote 50: Livingstone's "Expedition to the Zambesi."] Anyhow they turn from the autumn browns and reds to the appropriate green of spring, and the flowers come out and the birds begin to sing in the very season when our winter winds are loudest and the rock mills of the sea are roaring at their work. In which Hemisphere, the Northern or the Southern, do the sea mills have most land to work on? In Shakespere's "Tempest" you will find a description of a storm at sea that will take your breath away. Almost the whole of Scene 2, Act I, is in that terrible storm. In fact, the whole play, as the title of it indicates, is full of storm. While you are looking for storms in Shakespere see what you can find in "Two Gentlemen of Verona," "Twelfth Night," "Midsummer Night's Dream," and "The Merchant of Venice." Speaking of the sea still being in the Stone Age what do you know about the kind of tools man used in the Stone Age and how he got along?[51] (You'll find that the story of the development of man, as dealt with in connection with the Stone Age, is part of the strangest story of all the strange stories of science. You will get a brief outline of it in this story of mine, in the last chapter.) [Footnote 51: Interesting books on this subject are: Starr's "First Steps in Human Progress" (Chautauqua Reading Course) and Clodd's "Childhood of the World." Osborn's "The Men of the Old Stone Age" is the latest and most comprehensive work on the subject.]