An exclamation on seeing how Eliot’s poems were signed? (2,6)

I believe the answer is:

by george

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'an exclamation' is the definition.
(I've seen this before)

I don't understand how the rest of the clue works.

(Other definitions for by george that I've seen before include "Fancy that" , "planes might be flown thus?" , "the dragon was killed" , "Goodness" , "Anne succeeded so" .)

I've seen this clue in The Times.

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