1. Water Power ... 11. Conquistadors ...
2. Drought ... 12. American Indians ...
3. Water and Pollution ... 13. Lewis and Clark ...
4. The Tides ... 14. Yosemite ...
5. Desert Formation ... 15. The Arrival of the Puritans ...
6. Mirages ... 16. Puritan Influence ...
7. Forests ... 17. Thomas Jefferson ...
8. The Dust Bowl ... 18. The American Revolution ...
9. Weather ... 19. The Declaration of Independence ...
10. Earthquakes ... 20. Immigrants ...