Add to ORKGPatent for a new and improved washboard. This design consists in "a suitable base-frame, a series of alternately right and left handed spirally-grooved rollers journaled therein, an inclined forked frame straddling and pivoted to the base-frame, a lever for securing the adjustment of said forked frame on its axis, a rubber, and rocking spring-arms journaled in said forked frame and connecting the same and the rubber" (lines 92-100)