Thomas Carlyle was the author of a history of the French Revolution. He completed the first volume and sent it to a pal to read, the philosopher John Stuart Mill. Mill's maid mistook it for trash and used it as a firelighter. Carlyle had no copy. He rewrote the entire MS which, he said , came “direct and flamingly from the heart”.
In “A Moveable Feast”, Hemingway tells of seeing his first wife, Hadley, subject to unbearable suffering. She’d traveled by train to Geneva. When he met her she couldn’t stop crying.
He said no matter what dreadful thing had happened nothing could be that bad. Besides, they’d work it out.
When he heard what it was, he wasn’t so sure. On the way, Hadley had lost all the Nick Adams short stories about Michigan Hemingway had been working on for months. She’d lost not only the MSS but the carbon copies, too.
We have memory sticks. At the end of each day, we can update the memory script in seconds.
I know of one author who did this each evening without fail. But he made a fatal mistake. He forgot to keep the memory stick at a distance from his computer. All his research papers and his copies went up with his computer when a fire destroyed his garden study.