10. Storm Tracks for August for Ten Years 132 11. Storm Tracks for February for Ten Years 134 12. Average Maximum Temperature for July 195 13. Ocean Currents 196 14. Mean Annual Isotherms 200 15. Normal Wind Direction and Velocity for January and February 202 16. Normal Wind Direction and Velocity for July and August 204 17. Map of Climatic Energy 221 18. Density of Population in the United States, 1910 222 THE NEW AIR WORLD CHAPTER I ATMOSPHERES OF THE EARTH, THE SUN, AND THE PLANETS =How Atmospheres Are Formed.= Once there were no such things on the earth as hills and mountains, singing brooks, roaring rivers and vast oceans; and the delicately hued landscape, with its winding roads, hedges, flowers, green fields, and golden grain, had not evolved from the atmosphere. The earth had not yet cooled down to the condition of a solid crust, everything that the eye now sees existed in the form of invisible gases, or as clouds incandescent with white heat. Fiery blasts swirled over the face of the earth. Storms a million times more powerful than the most destructive West Indian hurricane of the present day moved through the indescribably hot atmosphere, throwing down not rain as we understand it, but liquid earth and metal, as their rising clouds ascended and cooled. It is difficult for the human mind to grasp the wonders of this. Small planets cool quicker than large ones and sooner come to the conditions of a crust and to a temperature suitable for the development of the various forms of life. =Atmosphere of the Sun.= To the unaided eye it appears as a smooth, bright, quiescent sphere, but the telescope reveals millions of agitations and hundreds of red flames that shoot outward to distances of hundreds of thousands of miles. One can form no adequate picture of the convulsions of the atmosphere of the sun. During eclipses, when the intense glare of its center is obscured, hydrogen flames may be seen darting outward for as much as a million miles.