The Board of Finance and Revenue shall determine the amount of money necessary for the payment of interest on the bonds and the principal thereof, if any, for the two fiscal years beginning June first, one thousand nine hundred and thirty-three, and the times and amounts of such payments; and the amount so determined shall be transferred from the Veterans' Compensation Fund to the Veterans' Compensation Sinking Fund, and, for such purpose, as much of the money in the Veterans' Compensation Fund as may be necessary is hereby appropriated. Should the moneys in the Veterans' Compensation Fund for any reason not be available for the payment of interest on the bonds or the principal thereof, if any, the funds necessary for such purpose are hereby appropriated from the General Fund; and whenever any moneys are transferred from the Veterans' Compensation Fund for the payment of said interest on, and principal of, said bonds, and such moneys are needed for the payment of compensation to veterans as provided by law, there is hereby appropriated from the General Fund a sum sufficient to restore to the Veterans' Compensation Fund the moneys so transferred.