B-7, an enclosed, seven-passenger snowmobile, in 1937, and introduced the B-12, a twelve-passenger model, in 1942. The B-7 had a V-8 flathead engine from Ford Motor Company. The B-12 had a flathead in line six-cylinder engine from Chrysler industrial, and 2,817 units were produced until 1951. It was used in many applications, such as ambulances, Canada Post vehicles, winter "school buses", forestry machines, and even army vehicles in World War II. Bombardier had always dreamed of a smaller version, more like the size of a motor scooter. Brands Early models Numerous people had ideas for a smaller personal snowmobile. In 1914, O. M. Erickson and Art Olsen of the P.N. Bushnell company in Aberdeen, South Dakota, built an open two-seater "motor-bob" out of an Indian motorcycle modified with a cowl-cover, side-by-side seating, and a set of sled-runners fore and aft. While it did not have the tracks of a true snowmobile, its appearance was otherwise similar to the modern version and is one of the earliest examples of a personal motorized snow-vehicle. In 1951 Dr. Fritz Riemerschmid devised what he called a snow scooter. The machine had a track mounted beneath a snowboard like base, on top of which were an enclosed engine with motorcycle like seat and fuel tank. the vehicle was steered via a steering wheel and cables linked to two small skis on outriggers either side of the vehicle. In the mid-1950s, a United States firm built a "snowmobile the arctic area of Alaska that had the drive train reversed of today's snowmobiles with two front wheels—the larger one behind the smaller one—with tires driving an endless loop track". Little is known about this "snowmobile" meant to haul cargo and trade goods to isolated settlements. An odd version of snowmobile is the Swedish Larven, made by the Lenko Company of Östersund, from the 1960s until the end of the 1980s. It was a very small and basic design, with just an engine in the rear and a track. The driver sat on it and steered using skis on his feet. Polaris Edgar and Allen Hetteen and David Johnson of Roseau, Minnesota, invented what we now know as the modern snowmobile in 1955–1956, but the early machines were heavy () and slow (). Their company, Hetteen Hoist & Derrick Co., became Polaris Industries which introduced their first commercial model, the Polaris Sno Traveler in 1957. BRP In 1960,