During the summer of 1915, Ithaca went to the bold floral engraving on their No. 1 1/2 Flues Model.

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By 1920, with the discontinuance of composite iron and steel barrels, Ithaca Gun Co. combined their No. 1 and No. 1 1/2 as the new No. 1 --

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According the the serial number chronology in the second edition of Walter's book, your gun would be of 1923 vintage. Closest I have is the 1924 Ithaca Gun Co. catalog --

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