The Act of March 4, 1911, (36 Stat. 1253; 43 U.S.C. 961), as amended, authorizes the head of the department having jurisdiction over the lands, under general regulations fixed by him, to grant an easement for rights-of-way for a period not exceeding 50 years, over and across public lands and reservations of the United States, for poles and lines for the transmission and distribution of electrical power, and for poles and lines for communication purposes and for radio, television and other forms of communication transmitting, relay and receiving structures and facilities to the extent of 200 feet on each side of the center line of such lines and poles and not to exceed four hundred feet by four hundred feet for superstructures and facilities to any citizen, association, or corporation of the United States, where it is intended by such to exercise the use permitted under the Act.