The court rightly held the tax deed void on its face. The interest of the county was assigned for thirty-seven cents less than the amount necessary to redeem. The statute authorizes an assignment for the amount necessary to redeem, and limits the authority of the officers. They had no authority to assign for a less sum. (Noble v. Cain, 22 Kan. 493; Douglass v. Lowell, 60 Kan. 239, 56 Pac. 13; Manker v. Peck, 71 Kan. 865, 81 Pac. 171.)

There was no error in refusing to permit the county treasurer to explain that he made an error in computation. If such evidence were admissible for any pur*218pose, which is doubtful, it would only emphasize the fact that the assignment was made for a sum less than the law authorized.

The judgment is affirmed.