Wrenches for fire hydrants shall be furnished by the superintendent of waterworks for the use of members of any fire company organized, or which may be organized in the city, and to such other persons as he may deem proper, and it is unlawful for any such person or member having charge of any such wrench to permit the same to be used for any other purpose than that authorized by the superintendent of waterworks. (Prior code § 7-1-6)