General Regulations, no. 4, Circular of General Information Regarding Grand Canyon National Park, Arizona (Government Printing Office 1928).

“RULES AND REGULATIONS
(Approved January 16, 1928, to continue in force and effect until otherwise directed by the Secretary of the Interior)
GENERAL REGULATIONS

    …The following rules and regulations for the government of the Grand Canyon National Park are hereby established and made public pursuant to authority conferred by the act of Congress approved August 25, 1916 (39 Stat. 536), as amended June 2, 1920 (41 Stat. 732), and the act of February 26, 1919 (40 Stat. 1175)…

    …4. Hunting.—The park is a sanctuary for wild life of every sort, and hunting, killing, wounding, capturing, or frightening any bird or animal in the park is prohibited.
    The outfits, including guns, traps, teams, horses, or means of transportation used by persons engaged in hunting, killing, trapping, ensnaring, or capturing birds or wild animals, or in possession of game killed on the park lands, shall be taken up by the superintendent and held subject to the order of the Director of the National Park Service, except in cases where it is shown by satisfactory evidence that the outfit is not the property of the person or persons violating this regulation and the actual owner was not a party to such violation. Firearms are prohibited in the park except on written permission of the superintendent. Visitors entering or traveling through the park to places beyond, shall, at entrance, report and surrender all firearms, traps, nets, seines, or explosives in their possession to the first park officer and in proper cases may obtain his written leave to carry them through the park sealed. The Government assumes no responsibilities for loss or damage to any firearms, traps, nets, seines, or other property so surrendered to any park officer, nor are park officers authorized to accept the responsibility of custody of any property for the convenience of visitors…

    …Any person who violates any of the foregoing regulations shall be deemed guilty of a misdemeanor and shall be subject to a fine of not more than $500 or imprisonment not exceeding six months, or both, and be adjudged to pay all costs of the proceedings.”