The engineer and officer Jakob Chrysostomus Praetorius drafted a construction made of oak wood, in the shape of a fish with sails and mobile rear. Allegedly, the plan was presented in 1762 to William, Count of Schaumburg-Lippe. After an initial rejection it was built in 1772 at the island fortress Wilhelmstein in a reduced version. It is said to have dived in the Steinhuder Meer, a large lake, for 12 minutes. As the lake has a maximum depth of 2.9 metres (9 ft 6 in) this claim is rather dubious.
The range of the 'pike' must have been rather limited. According to a local legend count Wilhelm wanted to sail with it to Portugal. Its military purpose was actually the following: in the event of a siege the 'pike' had to connect the fortification with the allies of Schaumburg-Lippe, especially Britain, Braunschweig-Lüneburg and Prussia.
Today a model and construction plans are exhibited in the military museum Wilhelmstein. The Wilhelmstein, an artificial island and fortress, was the planned base for the 'pike'.
- steinhuder-meer.de (in German) date retrieved 21 August 2016