b61-264 INCLINOMETER. Patent Level Co. Some of the levels with this design are marked as having been made by the Patent Level Co. of Bridgeport, CT, and have a May 8, 1866, patent date. The only level patent on that date was issued to Arthur Vandegrift of Cincinnati, so it has been attributed to him although it doesn't look that much like the patent. However, we have located a drawing of this level in an old Scientific American labelled "Shay's Level." Who was Shay? No idea. In any case, they are rare as hen's teeth. This is the older version with the elaborate eagle casting, marked only "Patent Applied For" (Rosebrook, Figures 13-5 and 13-6), and like most has a dry vial and cracked vial cover. From the collection of Don Rosebrook. Good 1000-2000