Some writers wholeheartedly supported the letter but were afraid to sign, Mr. Preston said. A few signed it and then backed out, citing the same reason. The Times ad, which cost $104,000, was paid for by a handful of the more successful writers.
Mr. Preston's longtime writing partner, Lincoln Child, is among those with qualms.
"I am very apprehensive," Mr. Child said. "Not all David and Goliath stories end happily for the little guy. But I think Doug did the right thing."
Amazon supporters point to a rival petition on Change.org. It is a rambling love song to the retailer. Signers sometimes append invective decrying the New York publishers for having the audacity to reject novels. "There is something wrong with a system that picks those who use their elitist ideas of art to choose who is published," reads a comment.
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The petition has 7,650 signatures. By comparison, a 2012 Change.org petition calling on Amazon to ban the sale of whale and dolphin meat drew over 200,000 signatures.
Mr. Preston is not one of those writers who checks his Amazon ranking on a regular basis, or even totes up his sales. He would rather be writing. But he recently thought he should get some numbers from Hachette. They came in the other morning, and they seemed worth sharing with his wife, Christine.
About half his book sales used to come from Amazon. But since the retailer started discouraging orders, his paperback sales are down 61 percent and his e-book sales are down 62 percent. His last novel, written with Mr. Child and published by Hachette in November, was "White Fire." A week before publication, 25,000 Amazon customers had ordered a copy.
Their new novel, "The Lost Island," came out Tuesday. It had only a few thousand pre-orders, all made before Amazon lowered the boom on Hachette and stopped selling forthcoming Hachette books.
Mrs. Preston, a photographer, studied the bleak sheet.
"It's gotten personal," she said. "I knew you were going to take a hit, but I had no idea it would be like this."
"Are you worried?" Mr. Preston asked. "Because you should be. What if Amazon says, 'Why should we sell Doug Preston's books? He's a thorn in our sides.' Guess what? All this goes away."
There is a lot to go. The shack itself is negligible, but the house a few steps away is spacious and splendid. It is set on 300 acres that have been owned by the Preston family for much of the last 100 years. Amazon has tried to use Mr. Preston's success against him, dismissing him as "rich" and thus not in touch with the masses of struggling writers.
"It makes me laugh," he said. "Tech company billionaires are calling a mere writer 'rich.' I think they're rattled."
— By David Streitfeld, The New York Times