The board of public education in school districts of the first class may, during any fiscal year, make additional appropriations, or increase the existing appropriations, to meet emergencies such as epidemics, floods, fire or other catastrophes, and to increase the salaries of the employes of the board, the funds therefor to be provided from unexpended balances in existing appropriations, from unappropriated revenues, if any, or from temporary loans. Such additional appropriations, and such temporary loans, shall be authorized by the affirmative vote of two-thirds of all the members of the board.

The board of public education shall have the power to transfer any unencumbered balance, or any portion thereof, from one appropriation to another, or from one spending agency to another, by the affirmative vote of two-thirds of all the members of the board.