نظام الزراعة
By the early 1850s the only Dutch state yards left were those in Vlissingen and Amsterdam. Meanwhile the Dutch state had found a new source of wealth in the Cultivation System implemented in the East Indies. It meant that more money became available for the navy, and investments went to these two establishments. This was just as well, because the invention of screw propulsion had just obsoleted the entire fleet of sail and paddle-steam ships that the Dutch had. The biggest screw ships that the Dutch needed, the steam frigates, were built in Vlissingen because of their draught. The Rijkswerf would built a large number of steam corvettes.