1. practice: iaxation!°Q ‘ I. The assessed value of the land owned by Adamson in Freedom township, in 1874, was $13,8Q0. The amount exempted from taxation was $20,000. The exemption could not be greater than one-half of the assessed value, unless it could be distributed as the order of the board contemplated. Code, Sec. 799; Chapter 45, Acts of 1874.

The effect of the decree of the court below is that the exemption cannot all be made upon the Freedom township assessment, for it would exempt all of the land owned by Adamson in that township.

In our opinion his rights cannot be determined by this proceeding, and this order of the board of supervisors cannot be reviewed by injunction. Injunction is not the proper remedy, even if the proper parties were before the court. The law constitutes the board of supervisors a special tribunal to equalize the taxes among the several townships, and for the determination of exemptions. It is not competent to ignore their action in the performance of their duties. and institute original pro*27ceedings by injunction. If they err their action must be reviewed upon appeal, or by certiorari. Macklot v. Davenport, 17 Iowa, 379.

The decree will be reversed and cause remanded, with directions to dismiss the proceeding.

Reversed.