TC25-255 BEVEL AND SQUARE. Halstead & Ackerman. An example of the first patented square & bevel, patented in 1855 by Halstead & Ackerman. This bevel is marked with the patent date along with maker which is unusual, worn but legible. Brass handle, 7-3/4" steel blade, bevel blade clean. Brass has some scratches and a few light pitting spots on blades. Good 75-150