The controller shall appoint a deputy controller and such other clerks as may be necessary, whose salaries shall be fixed by the commissioners and the controller, as provided by section seven of the act of thirty-first of March, one thousand eight hundred and seventy-six. The deputy controller shall, during the necessary or temporary absence of the controller, perform all his duties, and also in case of a vacancy, until a successor is qualified.
16 P.S. § 7354