Buckle has a securing mechanism patented in 1868 by William Cummings.
Cummings' invention involved three small rings soldered onto the back of the buckle, which kept the prongs from slipping out of place.
His name and the patent date of August 1868, as well as the manufacturer's name, are marked on the back of the chape.
Purchase, Susan and Jon Rotenstreich Gift, 2000 (2000.571).