The Glue Industry in the United States. The principal factories sem to have been in the vicinity of Boston, New York, Philadelphia and later on Cincinnati. One of the pioneer factories was at Marblehead, Mass., and probably secured its stock from the tanneries at Salem and Lynn. In most factories the glue liquors, after evaporation and other treatment, are poured into small rectangular galvanized iron pans and allowed to gelatinize, preferably in a chill room. Sometimes the pans are allowed to stand in cold water.
Many European factories have casting tables , which form the glue diredctly into cakes.
None of these have found general widespread use, and several have been tried and abandoned. Some of the European gelatin factories are said to employ such apparatus. If you'd like to learn more about Peter Cooper and his legacy, click here.