§ 320. Injuries to highways. Whoever shall injure any highway or bridge maintained at the public expense, by obstructing or diverting any creek, water-course or sluice, or by dragging logs or timber on its surface or by drawing or propelling over the same a load of such weight as to injure or destroy the culverts or bridges along the same, or of such weight that will destroy, break or injure the surface of any improved state highway, county road or town highway, or by any other act, or shall injure, deface or destroy any mile-stone or guide-post erected on any highway, shall for every such offense forfeit treble damages.