No extra compensation shall be granted or allowed by the Mayor and City Council to any officer, agent, or servant of the corporation, or of any other corporation the expenses of which are borne in whole or in part by the City, after the services have been rendered. Nor shall the salary or compensation of any of said officers, agents, or servants be increased or diminished during the term for which they may be or may have been elected, appointed, or employed. Provided, that should an increase of duties be required by any subsequent ordinance or resolution of the Mayor and City Council, an extra compensation in proportion for the increase of labor, to the original compensation, may be allowed, in the discretion of the said Mayor and City Council. City Code, 1879, art. 1, §47 1893, art. 1, §52 1927, art. 1, §61 1950, art. 1, §10 1966, art. 1, §12 1976/83, art. 1, §15 Ord. 1863-058