Clifton Woodridge (1854-1933), a Chicago detective in the early 1900s, wrote this popular account of the many arrests he made during his time on the Chicago police force. According to the PBS series History Detectives Wooldridge "was described at the time as 'the incorruptible Sherlock Holmes of America,' and he was on a mission to save Chicago from itself. He considered Chicago the 'wickedest city in the world.' It certainly had the right ingredients. Chicago was seen as the land of opportunity, or at least the gateway to it. People passed through on their way to homesteading further west, the railroad brought folks to the city, in the hopes they would find one of the many possible jobs in this burgeoning city. It became a hotbed for vice and corruption. As a police officer on the beat, Wooldridge saw what was happening. He battled everything: quack doctors, prostitution, gambling, investment swindles, insurance scams, fake banks, clairvoyants and marriage agencies. He associated with the down and out and the richest of the rich. Apparently he would stop at little to learn the ways of the criminal. Wooldridge was adept at disguising himself, and would dress for the part, whether it meant posing as a rube in from the country or even donning black face." (Check out some of Woodridge's disguises.