Collection of seventeen scientific essays

Part I: The Earth and Away
"Life's Bottleneck" (April 1959)
"No More Ice Ages?" (January 1959)
"Thin Air" (December 1959)
"Catching Up with Newton" (December 1958)
"Of Capture and Escape" (May 1959)

Part II: The Solar System
"Catskills in the Sky" (August 1960)
"Beyond Pluto" (July 1960)
"Steppingstones to the Stars" (October 1960)
"The Planet of the Double Sun" (June 1959)

Part III: The Universe
"Heaven on Earth" (May 1961)
"Our Lonely Planet" (November 1958)
"The Flickering Yardstick" (March 1960)
"The Sight of Home" (February 1960)
"Here It Comes; There It Goes" (January 1961)

Part IV: The Human Mind
"Those Crazy Ideas" (January 1960)
"My Built-in Doubter" (April 1961)
"Battle of the Eggheads" (July 1959)