The United States of America may acquire such educational lands, or portions thereof, in subdivisions of not less than forty acres, located within the boundaries of the projects now authorized by the United States of America pursuant to Public Law 848, 76th Congress, entitled An Act Authorizing the Construction of Water Conservation and Utilization Projects in the Great Plains and Arid and Semiarid Areas of the United States, approved August 11, 1939, and all acts supplementary thereto, amendatory thereof, or appropriating funds for the purposes thereof.