indefinite concession requiring survey

where there is a specific tract of land confirmed, according to ascertained boundaries, the confirmee takes a title on which he may sue in ejectment… But where the claim has no certain limits, and the judgment of confirmation carries along with it the condition that the land shall be surveyed, and severed from the public domain and the lands of others, then it is not open to controversy, that the title attaches to no land; nor has a court of justice any authority in law to ascertain and establish its boundaries, this being reserved to the executive department.