Earth's Air

This book is best read by starting with Chapter 3, then Chapters 1 and 2 in order. Chapter 3 is a story about two children who learn to deal with smoky air which has changed their plans for the day.
Earth has a life-supporting air layer which is unique among the planets of our solar system. Appreciating this awesome world is aided by a look into its workings. What is air, how does it support life? These are among the basic questions asked. The two children gain knowledge about the air, whil...