While browsing eBay, I came across a patent from George Conover, apparently used by Dean Thomas, for his book Round Ball to Rimfire. Part of the sellers description is quoted below.
“An Original 1864 Cartridge Patent Office Document used in research for the Dean Thomas book “Round Ball to Rimfire””
A full view of George Conover’s patent can be found here:
(I thought I would add this thread to our database, as searching for the name “Conover” was not showing up in our search engine)