The director of each department may prescribe regulations, not inconsistent with law, for the government of his department, the conduct of its employes, the performance of its business and the custody, use and preservation of the records, papers, books, documents and property pertaining thereto. * * * * * Sec. 154-14. Each officer whose office is created by sections 154-3, 154-5 and 154-6 of the General Code shall, before entering upon the duties of his office, take and subscribe an oath of office as provided by law and give bond, conditioned according to law, with security to be approved by the governor in such penal sum as shall be fixed by the governor, not less in any case than ten thousand dollars. Such bond and oath shall be filed in the office of the secretary of state. The director of each department may, with the approval of the governor, require any chief of a division created under the authority of this chapter, or any officer or employe in his department, to give like bond in such amount as the governor may prescribe. The premium, if any, on any bond required or authorized by this section may be paid from the state treasury. Sec. 154-15. The director of each department may, with the approval of the governor, establish and appoint advisory boards to aid in the conduct of the work of his department or any division or divisions thereof. Such advisory boards shall exercise no administrative function, and their members shall receive no compensation, but may receive their actual and necessary expenses. Sec. 154-16. Each officer whose office is created by sections 154-3, 154-5 and 154-6 of the General Code shall devote his entire time to the duties of his office, and shall hold no other office or position of profit. In addition to his salary provided by law, each such officer and each member of the boards and commissions in the departments created by this chapter shall be entitled to his actual and necessary expenses incurred in the performance of his official duties. Sec. 154-17. Each department shall maintain a central office in the city of Columbus. The director of each department may, in his discretion and with the approval of the governor, establish and maintain, at places other than the seat of government, branch offices for the conduct of any one or more functions of his department.