1. MisoHAmc’s lien: schoolhouse. — I. In Loring & Co. v. Small et al., 50 Iowa, 271, it was held that public bridges of a county cannot be made liable to a mechanic’s lien under the statutes of this state. The ground of the opinion in that ease is that the bridges are exempt from execution. For the same reason a mechanic’s lien cannot be established against a school-house.

2. —; attachment i wrong-mi release. II. In our opinion the district township is not liable for the value of the lumber, because the sheriff released the levy of the attachment and permitted Biglow to pro-x <-» i ceed with the building. If the district township could be made liable for the unlawful acts of its officers in converting the property of others (a question which we To not determine) such liability would not'arise upon the allegations of this petition. It is averred that the district township well knew the fact that said lumber had been levied upon. This knowledge is not sufficient. For auglit that appears the officers of the defendant may have bad reasonable grounds to believe that the levy on tlie lumber was released by the agreement of the parties to the attachment proceedings. They are, at all events, not presumed to have knowledge that the sheriff, in releasing the levy, was guilty of a wrongful act as a public officer.

Affirmed.