No person shall erect, construct or maintain, or cause to be erected, constructed or maintained, any billboard, sign, board or illuminated or other roof sign in such a manner as to be dangerous to the public by falling or being blown down; or constructed of such materials or dimensions as to be dangerous to the public by falling of structures in such a manner as to endanger the life or limb of any person; or in such proximity to buildings as to increase the danger of loss by fire; or to erect or maintain the same so as to obstruct the view of railroad crossings and thus endanger life by accident, or that shall have printed upon them obscene matter or characters tending to demoralize or injure the public morals.
(1955 Code. §985.05)