Such bonds shall mature in such annual series or installments as the authorities shall provide, except that:
(1) The first maturing bonds shall mature within three years from the date as of which they may be issued;(2) Not less than three per cent of the aggregate of the issue shall mature in any year; and(3) No bond shall mature later than twenty-five years from the date as of which it may be issued.The provisions of this section shall not prevent the authorities from issuing the aggregate of the bonds authorized by the election on one or more occasions as two or more issues.
1951 (47) 759; 1952 Code Section 21-977; 1962 Code Section 21-977.