The principles of this system of reciprocity, founded on the law of [1815-03-03], have been since carried into effect with the Kingdoms of the Netherlands, Sweden, Prussia, and with Hamburg, Lubeck, and Oldenburg, with a provision made by subsequent laws in regard to the Netherlands, Prussia, Hamburg, and Bremen that such produce and manufactures as could only be, or most usually were, 1st shipped from the ports of those countries, the same being imported in vessels wholly belonging to their subjects, should be considered and admitted as their own manufactures and productions.