Eclipse Day brings to mind Mark Twain's 1889 novel "A Connecticut Yankee in King Arthur's Court." It gets less attention than "Huckleberry Finn" but is as pertinent to modern times as that anti-racist classic. (And after events earlier this month, we need Huck as much as ever.)
"A Connecticut Yankee" begins as a farce and ends as a bleak modern tragedy. A 19th century practical-minded New Englander, Hank Morgan, finds himself transported back to the days of Camelot, where the strange outsider is immediately condemned to burn at the stake. It just so happens that he knows his astronomical tables, however, and that his execution date coincides with a solar eclipse. So he warns the court that if he's killed, he'll blot out the sun. When he appears to be making good on his threat, he gets a reprieve and he agrees to return the sun.
Much of the book is then taken up by his war against superstition (represented by Merlin) and religious monopoly (the medieval Catholic Church) and in favor of industrial and scientific progress. England gets an industrial revolution centuries ahead of its real one. It all sounds good until an army of knights makes war upon Morgan and his fellow advanced thinkers. Morgan sets up a defense of electrified wires and guns, and any last vestiges of romantic Arthurian escapism in the novel are lost. There's a wholesale slaughter of the knights, supposedly in a good cause, but Morgan and his supporters are ultimately trapped by the heaping, decaying bodies, and it doesn't end well.
The scenario describes uncannily well what would happen a quarter century later with the trench slaughters of World War I. And if anyone doubted the dark side of technological progress, the industrialized genocide of Nazi Germany proved it all too well.
The novel ends with less hope than love. After the pyrrhic victory -- spoiler alert -- Morgan lies dying, muttering calls to his one true love, the medieval lady he nicknamed Sandy.
Twain was an unapologetic skeptic of religion, and is often depicted by secular groups in their pantheon, or, pan-atheon, of heroes. But he also sounded an alarm about unintended consequences.