The board of chosen freeholders of each county of the first class may appoint for a term of 3 years a warden of the penitentiary, a warden of the county jail, a physician for the penitentiary and a physician for the county jail. The terms of office of all such officers now holding office shall expire on January 1, 1946 and thereafter all appointments shall be made for the term of 3 years. All vacancies in said offices caused by death, resignation or otherwise shall be filled by the board of chosen freeholders for the unexpired terms.
N.J.S. § 30:8-15