One of the earliest acanthus patterns. Called Florence or Dresden depending on the escutcheon. Knob shown is the 2 1/2 inch size. Dresden plate is bronze as per the 1895 Corbin catalog page 603. The other plate is in cast iron and slightly different. It must have been made more recently. Knob shown in 1895 Corbin catalog  pages 602 & 603 and 1896 catalog page 290 & 250.