Originally printed as an Ace Double with the Big time.
I believe the Ace Double edition is the only version to contain all the stories, Try and Change the Past is missing from later editions.
Years ago my window at the University of Chicago overlooked the west stands of Stagg Field. One evening I watched a lightning storm playing over the Loop.
Nature was badly off key that night. The thunder didn’t rumble or roar. It screamed faintly, four seconds after each flash. I remember thinking that if lightning could twang the rails of Chicago’s elevated tracks they might make such a sound. Several other persons heard it and shivered as I did.
Ten years later electronic experts discovered that on rare occasions lightning generates a radio signal which circles the earth and returns to its point of origin as an audible whistle. Maybe that was my scream.
But also ten years later there was built below the west stands of Stagg Field the graphite-dark atomic furnace that first released on earth the energy of the suns. Maybe the molecules felt that coming and screamed a warning.
Either way it’s a weird and wonderful world. Just consider: an infinite universe . . . stars that are living hydrogen bombs . . . trillions of atomic worlds in a grain of dust . . . jungles in a drop of water . . . black gulfs of space around each planet . . . black Freudian forests around each conscious mind—you know, I sometimes think the powers that created the universe were chiefly interested in maximizing its mystery.
That’s why I write science fiction.