Rubber was discovered in the 1700’s. Because it was temperature sensitive, not much was done with it. In 1839, Charles Goodyear accidentally dropped some rubber mixed with sulfur on top of a hot stove. Instead of turning into a gooey mess, the rubber “cured.” It was flexible and remained flexible the next day. He called the process vulcanization, after Vulcan, the Roman god of fire and patented the process is 1844.
Rubber Stamps came into use after the Civil War. They were made with regular printers type pressed into a plaster-of-Paris mold. Since the 1920s, the type was pressed into a piece of heated plastic/bakelite and rubber was pressed into this mold. This process allowed every “Mom and Pop” print shop and office supply store to make rubber stamps in the back room. This Warner Model 46 was popular in the 1960s. Many were built, many are still in use and many are available on eBay. Surprisingly, supplies are still available today. Click on the Drop-Down menu “Manuals” for pdf’s of several rubber stamp manuals.