P is a corporation of the Commonwealth of Pennsylvania, and is the owner in fee of 'Brunot's Island' in the Ohio River. In 1858, the high and low water lines in the Allegheny, Monongahela and Ohio rivers were determined by statute along with surveys according to the statutory authority. The statute declared that 'the lines so approved shall forever after be deemed, adjudged and taken firm and stable for the purposes aforesaid.' P asserts that all the land, whether or not underwater, inside of the Commissioners' lines became the property of the owners of Brunot's Island. A considerable portion of the shore of the island was washed away from time to time by heavy floods and freshets so that a large part of the upland was slightly submerged, but not to an extent sufficient to permit of navigation. The United States Government caused a dam to be constructed across the Ohio River which increased the depth of water in the channel, and submerged Brunot's Island to a far greater extent and to make the water over the complainant's land navigable 'at certain times and for certain purposes,' where it was not navigable before. In 1895, D, the Secretary of War, claiming to act under the authority of §12 of the act of Congress of September 19, 1890, established a harbor line which ran across P's land within the line of the State Commissioners. P alleges that the submerged land was not ordinarily navigable water and has never constituted, nor does it now constitute a part of the public navigable waters of the United States. P sued D claiming that no authority was conferred by the act of Congress upon D to regulate or interfere with the use of P's land. P claims the right to repair the damage caused by floods and to reclaim the submerged portion by filling in or wharfing, 'keeping at all times within the lines of the part that had been torn away by the violence of the waters.' D, claiming authority under § 11 of the act of Congress of March 3, 1899, changed the harbor line. P now desires to reclaim a part of the land, which had been submerged by establishing a coal wharf on the back channel. D noticed P that it had no right to build upon its land across either of the harbor lines, and he refused to permit P to reclaim its land or to build its wharf. P avers that it is prevented from making use of its property; that D's action constitutes a taking of its property for public use without just compensation; that it is subjected in its endeavor, so long as the harbor line remains unmodified, to a multiplicity of criminal prosecutions; and that the harbor line is a cloud upon its title. D demurred on a number of grounds one of which was it was a suit against the United. States. P appealed an affirmation of the granting of D’s demurrer.