The Smith & Wesson company was purchased by the Bangor Punta conglomerate in 1964, and BP also owned one of the early pioneers in police tear gas products, the Lake Erie Chemical Company. Once it had both companies under single ownership, the decision was made to rebrand the tear gas product line as the Smith & Wesson Chemical Company. S&W was obviously a brand with lots of recognition in law enforcement, so this was a good idea. S&W began production of a new model of 37mm tear gas launcher using the N frame revolver clockwork, coupled with a simple break action barrel. The system was available as either a pistol (7.5 inch barrel) or a stocked carbine (14 inch barrel) – and a nautical line-throwing version was also made. This is probably the finest quality tear gas or flare gun ever made, as the clockwork from the revolvers gives it a great single action and double action trigger pull compared to the typical utilitarian flare gun.
A variety of projectiles were made, including short-range, long-range, and barrier penetrating models (see poster below). These were all available loaded with smoke, CS, or CN gas. Production appears to have ceased in 1984, when the Bangor Punta conglomerate was bought out, and Smith & Wesson sold off from it shortly thereafter.
Source of the quote about Roush: