It shall be decided later on by the Powers, if any, and under what conditions, sanitary control shall be exercised over vessels navigating the river. ARTICLE XXV. The provisions of the present Act of Navigation shall remain in force during times of war. Consequently, the navigation of all nations, neutral and belligerent, shall at all times be free for the purposes of trade on the Congo, its branches, its affluents, and its mouths, as well as on the territorial waters fronting the mouths of the river. The traffic shall likewise remain free, notwithstanding the state of war, on its roads, railways, lakes and canals, as mentioned in Articles XV and XVI. The only exception to this principle shall be in cases in connection with the transport of articles intended for a belligerent, and held in accordance with the law of nations to be contraband of war. All the works and establishments instituted in execution of the present Act, particularly the offices of collection and their funds, the same as the staff permanently attached to the service of such establishments, shall be treated as neutral, and shall be respected and protected by the belligerents. * * * * * CHAPTER V. THE ACT OF NAVIGATION OF THE NIGER. ARTICLE XXVI. The navigation of the Niger, without excepting any of the branches or issues, is, and shall continue free for merchant vessels of all nations, in cargo or ballast, conveying goods or conveying passengers. It shall be conducted in accordance with the provisions of the present Act of Navigation, and with the regulations established in execution of the same Act. In the exercise of that navigation, the subjects and flags of every nation shall be treated, under all circumstances, on a footing of perfect equality, as well in the direct navigation from the open sea to the interior ports of the Niger, and _vice versa_, as for grand and petty coasting, and in boat and river work throughout its course. Consequently throughout the length and mouths of the Niger, there shall be no distinction between the subjects of the riverside States, and those of States not bordering on the river, and there shall be conceded no exclusive privilege of navigation to any society, or corporation or individual. These provisions are recognised by the signatory Powers as henceforth forming part of public international law, ARTICLE XXVII. The navigation of the Niger shall not be subjected to any obstacle nor duty based only on the fact of the navigation. It shall not be subject to any duties for harborage, stoppages, depots, breaking bulk, or putting into port through stress of weather. Throughout the length of the Niger, vessels and goods passing along the stream shall not be subject to any transit dues, whatsoever may be their origin or destination.