EACO Flour Mill and Loon Lake Colored Postcard. 5 1/4" x 3" hand-colored lithographed postcard of Loon Lake, Waseca, Minn; shown is the EACO Flour Mill across the lake, with a train loading or unloading goods beside the building; also visible is the Waseca County Courthouse, left edge; duplicate of another in the collection; see album page 3. EACO Mill.