The state treasurer shall be the custodian of the several accounts. He shall furnish the board a bond, the amount to be fixed by the board and approved by the governor. All payments from the said accounts shall be made by him only upon vouchers signed by two (2) persons designated by the board of trustees.
For the purpose of meeting disbursements for state annuities, teacher annuities, and other payments there may be kept available cash, not exceeding ten per cent (10%) of the total amount in the several accounts of the retirement system on deposit with the state treasurer.
T.C.A. § 49-1539