Model of a submarine, Antoine Lipkens, 1835 - 1840
The 19th century was full of experiments to create underwater vessels. Antoine Lipkens worked on developing a Dutch submarine. From his extensive studies, and trials by Uhlenbeck, this model was made. It incorporates several improvements, such as a centrifugal pump for propulsion. Due to a lack of financing, a full-size version of this model was never built. The first operational submarine entered service in the Royal Netherlands Navy only seventy years later.