TC25-98 SCREW-ARM PLOW PLANE. P. A. Gladwin & Co. Unhandled, with boxwood arms and nuts and boxed fence. B1 mark (four stars) with the "P" worn off. Some overall wear but no damage, threads have only a few small chips. There's a hinge-like device that locks the depth stop screw (brass with a patch of corrosion) which we've never seen before. Porter Gladwin was an inventive guy with several patents to his name, so maybe this was his idea, or it could have been added by an ingenious user. Good 100-200