EXCLUDING FROM THE OPERATION OF PROCLAMATION NO. 260 DATED JUNE 22, 1951 WHICH ESTABLISHED THE MINDORO AGRICULTURAL SCHOOL SITE RESERVATION SITUATED IN THE MUNICIPALITY OF NAUJAN, PROVINCE OF ORIENTAL MINDORO, ISLAND OF MINDORO, CERTAIN PORTION OF THE LAND EMBRACED THEREIN AND DECLARING THE SAME OPEN TO DISPOSITION UNDER THE PROVISIONS OF THE PUBLIC LAND ACT.