In Wilcox v. Jackson (1839) 38 U.S. 498, the Supreme Court announced the appropriation doctrine in the context of government use of public land. Wilcox involved land within a federal military post, Fort Dearborn in what is now downtown Chicago. The post had been established on public land in 1804. It had been occupied intermittently by federal troops and federal Indian agents until at least 1836. In 1837, a settler acquired from the General Land Office in Chicago a patent for a tract of land within Fort Dearborn. The Supreme Court held that despite the apparently valid patent, the patent holder held no title to the land because the land had been previously "appropriated" for military use. The Court defined "appropriated" as "nothing more nor less than setting apart the thing for some particular use." Id. at 512. According to the Court: "Whensoever a tract of land shall have once been legally appropriated to any purpose, from that moment the land thus appropriated becomes severed from the mass of public lands; and . . . no subsequent law, or proclamation, or sale, would be construed to embrace it, or to operate upon it; although no other reservation were made of it. Id. at 513, . The patent holder therefore "acquired no title whatsoever to the land in question." (Id. at 515.) The Supreme Court explained that a state has an undoubted right to legislate as she may please in regard to the remedies to be prosecuted in her Courts, and to regulate the disposition of the property of her citizens by descent, devise, or alienation. But when the property is part of the public domain of the United States: Congress is invested by the Constitution with the power of disposing of, and making needful rules and regulations respecting it. If a state were able to pass laws that could dispose of federal lands ... the practical result ... would be, by force of state legislation to take from the United States their own land, against their own will, and against their own laws.