Augustus H. Garland, Gordon N. Peay and Dudley E. Jones are hereby constituted a State Board of Supervisors of said election, who shall take an oath faithfully and impartially to discharge the duties of their office; a majority of whom shall be a quorum, and who shall perform the duties herein assigned them. Should a vacancy occur in said Board, by refusal to serve, death, removal, resignation, or otherwise; or if any member should become incapacitated from performing said duties, the remaining members of the Board shall fill the vacancy by appointment. But if all the places on said Board become vacant at the same time, the said vacancies shall be filled by the President of this Convention.