Ah, Qfwfq, you old scoundrel!
A sequence of short stories, with the most minimal framing device ever -- somewhere in the first sentence there is an italicized phrase, said Qfwfq, or its equivalent -- in which Qfwfq takes some scientific snippet and weaves a tall tale about how he had been there when it happened. Marvelous little concoctions of anachronisms, in a charming voice. The tale of how he was the last of the dinosaurs long after the others' extinction ends with him taking a train, for instance.
If the framing device were not clue enough, the science he uses, not to mention the tales he weaves, are not exactly compatible. Both the Steady State and the Big Bang get used, for instance. And his family tree would be very weird indeed to match all his tales. He keeps you reading through sheer verve of his tales.
I believe I read somewhere that he was inspired to write this in order to show how works of fiction could be derived from any inspiration. If so, he proved his case.