Important as is the Meuse to Belgium, her great highway is the Scheldt. To all intents and purposes an arm of the sea, the Scheldt is navigable for ocean-going vessels as far as Antwerp, 55 miles from its mouth. Without it, Belgium becomes practically an inland country, for its 42 miles of North Sea coast have no harbors of value. Yet the lower Scheldt is not Belgian nor even neutral; it belongs to Holland, through whose territories it passes for 45 miles of its course. And it has belonged to Holland since the sixteenth century, when the weakness of Spain and the strength of the Dutch fixed the northern boundary of the Spanish Netherlands. When the treaty of Westphalia (1648) confirmed the northern provinces in the possession of the left bank of the Scheldt, it also gave them the right to close completely the mouths of the river and its tributaries. The purpose of this was to favor Amsterdam and Rotterdam, and in consequence grass grew in the streets of Antwerp. The revival of Belgium’s great port became possible only with the French Revolution, which reopened the river, while the treaty of Vienna declared navigation free on the Scheldt as well as the Meuse. The existing state of affairs on the Scheldt was established by the treaty of 1839, which created “a special regime which is neither that of the sea nor that of ordinary rivers.” The regime created by the treaty of 1839 has never been satisfactory to the Belgians. One of its provisions reads:[15] So far as regards specially the navigation of the Scheldt and of its mouths, it is agreed that the pilotage and the buoying of the channel, as well as the conservation of the channels of the Scheldt below Antwerp, shall be subject to a joint superintendence, and that this joint superintendence shall be exercised by commissioners to be appointed for this purpose by the two parties. Moderate pilotage dues shall be fixed by mutual agreement.