If, in order to maintain sufficient moneys on demand deposit in any fund as provided in Section 3.04.210 of this chapter, it becomes necessary to transfer or sell any securities of such funds, the officers specified in Section 3.04.220 of this chapter may transfer said securities to any other fund or funds in which there are temporarily idle moneys, or shall sell such securities and for such purpose they shall have authority to make any necessary written directions, endorsements or assignments for and on behalf of the city. (Prior code § 1-604)