Rules of the Prairie Shooting Club of Chicago, 1874
Adam Bogardus, Field, Cover, and Trap Shooting, "Pigeon Shooting", 1874
https://books.google.com/books?id=HxRIAAAAIAAJ&pg=PA299

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The Notting Hill Rule No. 1 of 1879
https://books.google.com/books?id=T0U9AAAAYAAJ&pg=PA25&lpg
The gun must not be carried to the shoulder till the shooter has called “Pull." but does not specify the "ready" position

A.B. Frost in “The Illustrated Sporting and Dramatic News” April 6, 1878

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In A.H. Bogardus, Field, Cover, and Trap Shooting, 3rd Edition, 1891 there is no mention of the "ready" position
https://archive.org/stream/fieldcovertrapsh01boga#page/444/mode/2up

Monte Carlo about 1898, before the new clubhouse and walkway. The shooter is using the low gun "ready" position

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1920

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