Monuments erected by the government surveyor to mark the section corners according to his survey will control, although in conflict with his field notes. If the monuments have been obliterated, but their location can be ascertained from testimony of witnesses who know and testify to the fact, the site thus established will control. If the monuments have been destroyed, and their original location cannot be established by other proof, recourse may be had to the field notes which are to be accepted as presumptively correct, and can only be overcome by clear and satisfactory evidence. State v. Ball, 90 Neb. 307, 133 N.W. 412 (1911). See also Neb. Rev. Statutes §23-1908.