Design Patent # D3732 by William Gorman November 2, 1869 and assigned to Russell & Erwin . Made of "Lava" in black, brown & buff. The 1887 Russell & Erwin catalog page 261 noted change in shank size.For additional information on Lava knobs seeThe Doorknob CollectorNumber 141 Click on each photo below to view additional images and information.