It is unlawful for any person to expectorate on the floors or walls of any public conveyance, public building or building open to the general public, or on any sidewalk in the City. Every person convicted of a violation of this section shall be punished by a fine of not more than $5.00 or by imprisonment for not more than two days, or by both such fine and imprisonment. [Code 1970 § 9.64.060; Code 1954 § 10-5.116.]