Design patent # D4100, June 7, 1870 by L. Kreuzinger.  Shown in 1875 R&E catalog page 382, 2 1/4, & 2 1/2 inches in diameter. Another triumph by MCCCo and Kreuzinger.  Marked "Made by Russell and Erwin Mfg. Co." Also pictured are bell pull and bell pull plate. Also in 1882 catalog page 299. Click on each photo below to view additional images and information.