It is unlawful for any person to build a fire, slack lime, mix mortar, or place any sand or gravel, building material or other substance upon any sidewalk, street or alley in said city without first obtaining a permit to do so from the chief of police. And whenever a fire is built or lime is slacked, or mortar is mixed, or sand or gravel or other like building material is deposited upon any sidewalk or paved street, the same shall be done in such a manner as to prevent injury to such sidewalk or pavement and to prevent the materials from coming in contact therewith or being scattered thereon. (Ord. 18 § 3, 1949).