Gelatin is a by-product of butchering. It is collagen taken from connective tissues, hides, hooves, and bones. Any gelled meats, such as hams, and all aspics are made from it. So are gelled sweet dishes such as B. Heller’s Jell-Jell.

Label for Jell-Jell

B. Heller and Co. Collection 1896-2003.  Special Collections, University of Chicago Library.