
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Cattle Going to Work - Impression of Morning by Constant Troyon (1855)

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Haystack Morning Snow Effect by Claude Monet (1891)
Around 1859, at 19, Claude Monet, with a letter of introduction from the painter Eugène Boudin, met Troyon and supposedly asked to be his student but the self-taught Troyon declined.
Of course, calling it plagiarism is a stretch. One difference is the size. Troyon's painting is huge. 102.25 x157.5 inches. Monet also did large paintings but I think his larger paintings are the water lilies and his more conventional landscapes are of a more conventional size. I could be wrong. The other difference is that Troyon was never as impressionistic as Monet but my first reaction to Cattle Going to Work reproduced in a book was "Ah, a Monet?"