This .357 Registered Magnum (reg. no. 2127) is one of only 839 S&W manufactured with a 6 inch barrel and was registered by Winnetka, Illinois, Chief of Police W.M. Peterson. The .357 Magnum was the most powerful handgun cartridge at the time, and this “state of the art” handgun quickly gained popularity with law enforcement agencies, including the FBI, looking for a sidearm to deliver more stopping power. "M0659360" is hand marked on the trigger guard. Matching serial numbers are on the butt, right grip panel, cylinder, and ejector shroud. Comes with a correct S&W model box. The accompanying factory letter states the revolver was shipped on April 8, 1937, and delivered to Von Lengerke & Antoine Co., 35 South Wabash Ave., Chicago, Illinois, with a 6 inch barrel, Call gold bead front sight (currently fitted with a Marble no 35F front sight), square notch rear sight, blue finish and checkered walnut Magna grips. The accompanying original registration certificate confirmed the revolver's configuration as listed in the factory letter and indicates that the revolver was registered by W.M. Peterson. Peterson was the chief of police for the City of Winnetka, Illinois. His chief of police business card is included as well as two original photographs of Chief Peterson (one picture shows Peterson as a young man, and the other picture shows him on the job as chief of police at a fire) and the pictorial paperback book "Images of America: Winnetka" that published a City of Winnetka's official photograph of Chief Peterson and the police officers he commanded (page 35). Also included is a collection of signed correspondence between Chief Peterson and notable members of law enforcement such as Director of the Federal Bureau of Investigation J. Edgar Hoover and Public Enemy Number One era FBI agent Melvin Purvis. In one letter Director Hoover congratulated Peterson on winning the election for First Vice President of the Association of Chiefs of Police. In another letter Hoover sent Peterson his remarks he delivered to Congress in April 1940. Letters from Purvis were professional as well as cordial. In one letter Purvis apologized to Peterson for not seeing him when he played golf in Winnetka and hoped to see Peterson soon for "a little chat." The letter was signed "Mel." Other letters are related to FBI investigations into possible Third Reich and communist sympathizers. In a June 1941 letter, for instance, an FBI special agent requested Peterson to investigate three high school students and their families as the students had shown signs of supporting the Third Reich at a school play. At least one student was known for carrying a copy of "Mein Kampf" to which he called his "bible." Provenance: The Dave Ballantyne Collection