each province exerted itself to trade internally as much as possible, and thus to evade the rules. earnings could only be maintained through smuggling and the confiscation of smuggled goods, a lesson especially learnt by the admiralty in amsterdam. on the river oude rijn there was an outpost of the arnhem office of the amsterdam admiralty. the rhine customs officer, however, whose jurisdiction extended as far as lobith on the border with the holy roman empire (since 1648), was under the authority of the admiralty of rotterdam.