P.T. Barnum was the founder of the "Greatest Show on Earth," one of the most impressive circuses in U.S. history, where, according to its histrionic creator, George Washington's 161-year-old former wet nurse also performed, as well as displaying the shiny-tailed Fiji mermaid and the very well-preserved skeleton of Christopher Columbus. A successful author, philanthropist, politician, but also a victim of financial downfalls and resurrections, considered a con man, referred to at the time as the "Shakespeare of advertising," he wrote in 1880 this short manual to illustrate to ordinary mortals how to make money, and especially how to hold on to it with a few simple rules including not following the wrong calling, being systematic, reading newspapers, using the best tools, and preserving one's integrity.