The provisions contained in Sections 10.78.150 through 10.78.180 shall not apply to any vehicle operated by any officer on employee of the city in the course of performing his duties as such, non shall the provisions contained in Sections 10.78.150 through 10.78.180 apply to any truck or any person or firm delivering supplies or materials for use upon such park. (Ord. 221 § 2, 1958)