B66-536 JOINTER. Hardt Patent. Louis Hardt of Yuba City, CA, patented this thing in 1893. It featured a nose piece that slides on an inclined plane to adjust the depth of cut. The patent shows a wooden plane, but the very few known examples are all cast iron, and most are smoothing planes. This is the super rare 24" jointer, identical to the one shown in Figure 262 of PTAMPIA I. Like all known examples, it has a marked Sargent cutter and Sargent horseshoe frog, but the lever cap has "Hardt" cast on the underside. Japanning 95%, some some small chips to tote edge and throat but otherwise a very nice example of one of the holy grails of patented plane collectors. Good+ 2000-4000