The coroner of any county may appoint one or more deputies to be approved by the judge of the circuit or by any circuit judge presiding therein, who shall take and subscribe the oath prescribed by the Constitution prior to entering upon the duties of his appointment. The oath may be administered by any officer authorized to administer oaths in the county. The appointment must be evidenced by a certificate thereof, signed by the coroner, and shall continue during his pleasure. The coroner may take such bond and surety from his deputy as he may deem necessary to secure the faithful discharge of the duties of the appointment, but the coroner shall always be answerable for the neglect of duty or misconduct in office of such deputy. When duly qualified, as herein required, the deputy so appointed may do and perform any or all of the duties appertaining to the office of his principal.