M-209

In cryptography, the M-209, designated CSP-1500 by the United States Navy (C-38 by the manufacturer) is a portable, mechanical cipher machine used by the US military primarily in World War II, though it remained in active use through the Korean War. The M-209 was designed by Swedish cryptographer Boris Hagelin in response to a request for such a portable cipher machine, and was an improvement of an earlier machine, the C-36.

The M-209 is about the size of a lunchbox, in its final form measuring 3.25 by 5.5 by 7 inches (83 mm × 140 mm × 178 mm) and weighing 6 pounds (plus 1 pound for the case). It represented a brilliant achievement for pre-electronic technology. It used a wheel scheme similar to that of a telecipher machine, such as the Lorenz cipher and the Geheimfernschreiber.

Basic operation

Basic operation of the M-209 is relatively straightforward. Six adjustable key wheels on top of the box each display a letter of the alphabet. These six wheels comprise the external key for the machine, providing an initial state, similar to an initialization vector, for the enciphering process.

M-209 (Michigan highway)

M-209 was a state trunkline highway in the lower peninsula of the US state of Michigan. It was located in Leelanau County in the Sleeping Bear Dunes National Lakeshore. Until it was decommissioned, it was Michigan's shortest state highway. M-209 started at M-109 and went 0.543 miles (0.874 km) or just 956 yards (874 m) to Glen Haven. In 1996, M-209's designation was "abandoned", and the road was turned over to the jurisdiction of the Leelanau County Road Commission.

Route description

M-209 was the short connector route from M-109 to the Glen Haven unit of the Sleeping Bear Dunes National Lakeshore west of Glen Arbor. The southern terminus of the highway was at the intersection with M-109 south of Glen Haven, a restored logging village on the shore of Lake Michigan on the Leelanau Peninsula. The roadway ran north from this intersection where M-109 made a 90–degree corner through the south and east legs of a four-way intersection with M-209 and Dune Valley Road. M-209 ran past such attractions as the restored General Store and Blacksmith Shop. Also located in Glen Haven is the former Glen Haven Canning Co. building. This building was first used as a warehouse and later as a cannery for cherries in the 1920s. It has since been restored as the Cannery Boathouse housing historic wooden boats used in the Manitou Passage between Glen Haven, Glen Arbor and the North and South Manitou Islands. The northern terminus of M-209 was located in front of the former U.S. Coast Guard Life Saving Station, now restored as a maritime museum. The museum is located at the intersection of Glen Haven Road and Sleeping Bear Dunes Road. At the time of decommissioning, M-209 was a two-lane, paved road.