Enjoyable novella (1950) about a character that goes forward in time and discovers that he can't return. So he keeps going forward, thinking he'll reach a time where someone will have figured out how to go back. An epic look at time, not unlike he wrote twenty years later in Tau Zero.

Again Saunders thought, what a strange company they were, four humans from the dawn and the dusk of human civilisation, thrown together at the world’s end and walking to greet the last of the gods.

Two scientists have successfully returned from their first trip into the future, but their next trip in the time machine goes badly wrong when it becomes apparent that returning from any further than 30 years in the future is impossible because it takes too much energy. Saunders’ only hope of ever seeing his fiancée again is to keep travelling forward in the hope that future ages will have solved this problem.

I liked this novella, and it had an interesting solution to the time travel problem. ( )