Ray Cummings' Explorers into Infinity is a speculative romance of impossible scale, where the universe may be as boundless inward as it is outward. When weary interplanetary mail worker Frank is summoned to the Gryce estate, he finds a quiet household transformed by a secret scientific obsession: Dr. Gryce and his brilliant children have spent years probing the structure of matter, time, and motion, convinced that worlds may exist within atoms just as stars fill the heavens. Their discovery begins with the myrdoscope, a device that reveals an immense outer realm and a startling vision of a beautiful alien girl threatened by grotesque beings and a giant presence. From that revelation comes an even bolder breakthrough: a tiny but fully functional vehicle capable of changing size, position, and time-rate, allowing human explorers not only to observe infinity but to enter it. Frank watches as Brett and Martt vanish into the unknown, then endures days of fear before their scorched craft returns from Mars. Older, changed, and carrying the burden of months spent in another temporal scale, the travelers begin a tale of peril, scientific wonder, and a voyage far beyond the limits of ordinary human perception. This edition has been fully restored with modern typesetting, custom cover design.