So here's the newest find of a lithographer firm that issued an advertising note.
H. Gugler & Son, Bank Lithographers
German born Henry Gugler moved to New York to do freelancing as an engraver. He worked for several bank note engraving companies in New York City. In 1863 the National Note Bureau of Engraving and Printing hired him as one of their first vignette engravers. Gugler worked as a bank note engraver in Chicago in 1870. He moved to Milwaukee to join his son, Julius Gugler, who was working with Henry Seifert as a lithographer. The three artists went on to form Seifert, Gugler and Company (a.k.a. Milwaukee Lithographing and Engraving). Gugler and his son formed their own firm, H. Gugler and Son, in Milwaukee in 1878. Upon his death in 1880, Julius took over the business and continued it as the Gugler Lithographing Co. - the oldest lithographic firm in Wisconsin. Gugler & Son produced checks and depression scrip.
While working for NNBE&P in Washington D.C. he did famous engravings of Abraham Lincoln and General Ulysses S. Grant. His life size steel engraving of President Lincoln would be his most important work and was completed in 1869 after two years of work.