For the purpose of inducing industrial enterprises to locate within the city or immediate vicinity thereof, and thus promoting a sound and proper balance between agriculture, commerce and industry and thus enhancing the general welfare of the citizens of the city, it is hereby declared necessary and desirable that the city make and issue its revenue bonds, payable solely out of the income to be derived from the rentals to be received from the leasing or sale of a project or projects to be acquired and owned by the city and that the city irrevocably pledge such income to the payment of such bonds and interest thereon, the proceeds thereof to be used solely for the purpose of acquiring by construction or purchase, or either, or a combination thereof, a project or projects. (Ord. 310, 5-2-1960)