What is the mystery centered in Jupiter's famous "Red Spot"? Two fighting Earthmen, caught by the "Pipe-men" like their vanished comrades, soon find out.
When you have an engine with no fuel, and fuel without an engine, and a life-and-death deadline to meet, you have a problem indeed. Unless you are a stubborn Dutchman--and Jan Van Artevelde was the stubbornest Dutchman on Venus.
In one place, a descendant of the Vikings rode a ship such as Lief never dreamed of; from another, one of the descendants of the Caesars, and here an Apache rode a steed such as never roamed the plains. But they were warriors all.
The ultradrive had just one slight drawback: it set up a shock wave that made suns explode. Which made the problem of getting back home a delicate one indeed...
To upset the stable, mighty stream of time would probably take an enormous concentration of energy. And it's not to be expected that a man would get a second chance at life. But an atomic might accomplish both--