First published in 1974 together with Before The Golden Age Volumes I – III in one books, the fourth volume of Asimov’s personal view of sci-fi in the late 1930s contains nine memorable stories – most of which had not been published before – including one by Asimov himself.  In this volume: He Who Shrank, Henry Hasse: A man discovers worlds nested within a universe with apparently endless levels of scale.  The Human Pets of Mars, Leslie Frances Stone: Martians land on a golf course in Washington, D.C., and capture a small group of humans, transporting them back to Mars to be kept as pets. The Brain Stealers Of Mars, John. W. Campbell Jr: Two former atomic workers, now outlawed, flee to Mars with newly developed weapons and discover a telepathic life form that mimics any other life form and is impossible to separate one from other duplicates.  The outlaws want to return to Earth but must eliminate the imposters first. Devolution, Edmond Hamilton: Perfect beings, alien colonists on a pre-biotic Earth, slowly, over time, devolve in lesser beings – less able and less moral…Big Game, Isaac Asimov: A drunk man tries to convince his audience that ten years ago he built a time machine and travelled back to before the extinction of the dinosaurs, where he met an intelligent race of humanoid dinosaurs who communicated with him telepathically. This story was believed lost for many years until a fan discovered it in the archives of the Boston University Library and returned it to Asimov. Other Eyes Watching, John W. Campbell Jr.; Minus Planet, John D. Clark: Two eagle-eyed astronomers discover a massive planetoid is about to hit Earth. Past, Present, and Future, Nat Schachner: Kleon, from Greece two millennia ago and Sam Ward, an American of the mid-twentieth century, enter suspended animation and are awakened after 10,000 years, to find a world transformed. The Men And The Mirror, Ross Rocklynne: Jack Colbie of the Interplanetary Police is in pursuit of interplanetary criminal Edward Deverel  when they inadvertently slip onto the frictionless surface of an enormous concave mirror built by unknown alien beings, and must use the laws of physics to escape. Cover art by Tony Roberts.