(a) In addition to all the other powers now granted by law, the city council of any city of more than 500,000 inhabitants shall, by ordinance, provide for the payment of a pension from the corporate fund of such city to any city employee who has served the city in an elective capacity for 18 or more years and who subsequently has served such city as an employee for a period of time which when added to the period of his service as an elective official aggregates a total service of 30 or more years, and who is not eligible for participation in any established pension fund or any established annuity and benefit fund, upon such employee reaching age 65 or more and whose service shall be terminated by resignation or otherwise.
     (b) The pension herein authorized under paragraph (a) shall be an annual pension of 60% of the annual salary or compensation paid to such employee during the last year of his service, provided that such annual pension shall not exceed $1800.
     (c) The pension herein authorized to be granted shall be paid to the person entitled in the same manner as his salary was paid during his last period of service by appropriations from moneys in the corporate fund of such city in the annual appropriation bill.