“Article XVII. The obligation shall not be so far extended, as that all friendship and mutual commerce with the enemies of that Ally (that requires the help) shall be taken away; for supposing that one of the confederates should send his auxiliaries, and should not he engaged in the war himself, it shall then be lawful for the subjects to trade and commerce with that enemy of that Ally that is engaged in the war, also directly and safely to merchandise with such enemies, for all goods not expressly forbid and called contraband, as in a special treaty of commerce hereafter shall be appointed.