Nevertheless he was wise enough to neglect no precaution to ensure the safety of his travelling tour. It was in no empty, braggart spirit that he made war upon so tough an enemy in so difficult a country. Charles II., in pursuance of the treaty of Dover, declared war upon the Dutch in March, and Louis trusted to him with the assistance of one hundred and twenty French vessels to keep the formidable Ruyter quiet in port, while the great effort was being made by land. Charleroi was chosen as the basis of operations, and large stores of every warlike necessity were collected there by Louvois with the utmost diligence. Further magazines were established at the advanced post of Neuss near Dusseldorf in the electorate of Köln. No longer, as in the days of Wallenstein, was war to support war, but for the first time in modern warfare the army was to be regularly provisioned from its base by means of magazines established along the line of route. In the early spring 176,000 men were massed at Charleroi under the orders of Condé and Turenne. On the 5th of May Louis joined the army and the storm burst upon the devoted Dutch.[4] [Sidenote: =Campaign of 1672.=] Marching down the Meuse valley past Liége and Maestricht, masking the latter fortress as he went, an operation hitherto unconceived of, he turned sharply to the right at Ruremonde and reached his magazines at Neuss on the Rhine safely on the 31st. Having thus gained the Rhine valley he pushed Condé over the river at Kaiserwerth to sweep the right bank and capture Wesel, while Turenne marched down the left bank and made himself master of the smaller fortresses of Orsoy Rhynberg and Bürick. On the 6th of June Turenne rejoined Condé at Wesel, and the whole army poured down the right bank unchecked across the frontier of Guelderland, until it was brought to a stop on the 11th by the little stream of the Yssel, behind which William was posted at the head of all the available Dutch troops. The hesitation was but momentary. Instead of forcing the line of the Yssel in the face of the enemy, always a most hazardous operation, Turenne determined to turn it. On his left flank as he faced William on the Yssel ran the broad but fordable stream of the old Rhine, which, leaving the main branch of the river, called the Waal, in a northerly direction, receives the water of the Yssel a few miles farther down at Arnheim, where, turning again to the west, it flows on to the sea. Half-way between Arnheim and the junction of the Waal and the Rhine is the ford of the Tolhuys. There, on the 12th of June, Condé crossed the old Rhine with his cavalry almost without opposition. On the next day a bridge was thrown across the stream, and the king and the whole army followed. After securing Nimwegen in his rear, Louis marched down the left bank of the old Rhine and crossed it again a little below Arnheim without difficulty. He had thus completely turned William’s position on the Yssel and conquered