This is typical. De Camp's worlds always feel real and thoroughly lived in. When he wrote of things, he knew whereof he spoke. He learned to fence and to ride a horse. He traveled widely all over the world, which helps make his series of historical novels set in classical Greek and Hellenistic times?The Dragon of the Ishtar Gate, The Arrows of Hercules, An Elephant for Aristotle, The Bronze God of Rhodes, and The Golden Wind?uniquely authoritative. Along with the novels of Mary Renault, de Camp's give the modern reader the best feel for what it was like to live in those times.

Trained as an engineer (unlike yours truly, he graduated from the California Institute of Technology), Sprague entered the job market during the Depression, when, essentially, there was no job market. The only time he worked in engineering was during World War II, as a naval officer stationed in Philadelphia, where he, Robert A. Heinlein, and Isaac Asimov fought the war with flashing slide rule, as he was fond of saying.

He used his technical training in his writing, though (to writers, nothing ever goes to waste), both in his fiction and in informative, lively nonfiction on subjects as diverse as engineering in the ancient world, Atlantis, the elephant, American inventions in the nineteenth and twentieth centuries, dinosaurs, and the Scopes monkey trial. He wrote an authoritative biography of H.P. Lovecraft, and another of Robert E. Howard.

I first made his acquaintance more than twenty years ago now, after I had a novelette in Asimov's and George Scithers, who was then editing the magazine, mentioned in the front material my debt to Lest Darkness Fall. Sprague sent George a postcard for forwarding to me, saying he'd liked the story and was pleased he'd had something to do with the shape of my career. I walked on air for days after that. When I published a translation of a Byzantine chronicle a year or so later, I sent him a copy, wondering if he might use incidents from it in fiction of his own (so far as I know, he never did).