A covenant that there are no incumbrances on the land conveyed; a stipulation against all rights to or interests in the land which may subsist in third persons to the diminution of the value of the estate granted. Bank v. Parisette. 68 Ohio St. 450. 67 N. E. 896: Shearer v. Banger. 22 Pick. (Mass.) 447; Sanford v. Wheelan. 12 Or. 301. 7 Pac. 324.