The Chimera eventually moved to the Uffizi, and then again to the National Archaeological Museum of Florence, where it can be seen today, a splendid example of the imaginary turned nearly real.

WSJ: The Imaginary Made Nearly Read | The Chimera of Arezzo | Masterpiece by Judith H. Dobrzynski

There's also a 1936 first edition of the Proceedings of the London Mathematical Society where mathematician Alan Mathison Turing introduces the concept of a "universal machine, " an imaginary computing device.

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