This is a quote from the book "Animal Farm" by George Orwell
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By the autumn the animals were tired but happy. They had had a hard year, and after the sale of part of the hay and corn, the stores of food for the winter were none too plentiful, but the windmill compensated for everything. It was almost half built now. After the harvest there was a stretch of clear dry weather, and the animals toiled harder than ever, thinking it well worth while to plod to and fro all day with blocks of stone if by doing so they could raise the walls another foot. Boxer would even come out at nights and work for an hour or two on his own by the light of the harvest moon...

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