Screw propulsion is a novel form of vehicular locomotion that is essentially as old as the automobile itself but never quite caught on. Noteworthy examples in America include utility vehicles developed by Jacob Morath (1899) and the Peavey brothers (1907). Perhaps the most well-known application of screw drive was the Armstead Snow Motor system marketed for Fordson tractors in the 1920s, converting the farm vehicles for use in deep snow.
In the early 1960s, Chrysler Defense Engineering worked on amphibious land/water vehicles using twin helical screws, arriving at the vehicle featured in this video, the Chrysler Marsh Screw Amphibian, in 1963-64. Powered by a 225 CID Chrysler Slant Six, this machine could travel on land, swamp, or water with fair speed and impressive maneuverability. As many as 10 units were built, and at least one is still in existence mothballed at the U.S. Army Corps of Engineers Waterways Experiment Station in Vicksburg, Mississippi.