Section 42.  Appropriations lapse after one year.
   All appropriations shall lapse at the end of the budget year to the extent that they shall not have been expended or lawfully encumbered. Any unexpended and unencumbered funds shall be considered a surplus at the end of the budget year. Any expenditure of such surplus or unbudgeted funds in a subsequent year shall be by amendment to the budget to be adopted in the form of an ordinance.