The next year he prepared to push his success further. Instructing the Dutch to advance on the right wing into Flanders, capture Antwerp, and seize the line of the Scheldt, he with the left wing pushed down the Rhine, overran the electorate of Köln, and in May 1703 made himself master of Bonn. He was now secure of his communications with north Germany, and was preparing to organise a German army to operate upon the Moselle, and keep up communications between himself and the Emperor, when he was recalled to the Netherlands in hot haste to assist the Dutch. Tired of waiting for the siege train and transport necessary to form the siege of Antwerp, the Dutch had begun to send out detachments into Flanders for pure plundering purposes. One of these under Opdam was suddenly attacked by Boufflers, and completely destroyed in June 1703. Whereupon the Dutch, in the extremity of terror, absolutely refused to undertake the siege of Antwerp at all. On Marlborough’s arrival Boufflers withdrew behind the lines of the Mehaigne, which he had carefully fortified by ramparts and towers. Marlborough, sure of his ability to force the lines, made preparations for the attack, but the Dutch declined to co-operate, and the English general, baffled and dispirited, was obliged to content himself with the capture of a few inferior fortresses. [Sidenote: =Advance of the French upon Vienna, 1703.=] Meanwhile on the upper Rhine things were going badly for the allies. Louis had always intended to make his main attack in this quarter. His plan included a simultaneous advance upon Vienna by the Danube and by Italy, with the help of the duke of Savoy and the elector of Bavaria, while Boufflers in the Netherlands merely kept the English and the Dutch army occupied and entangled amid fortresses and fortifications. The success of prince Eugene in Italy, and his own want of preparation delayed for some time the commencement of this movement, but by the beginning of the year 1703 all was ready. Vendôme was facing prince Eugene upon the Adige ready to attack. The elector of Bavaria had definitely declared himself on the French side and captured Ulm. Accordingly in February 1703 Villars crossed the Rhine at Strasburg, took Kehl by storm, forced the passes of the Black Forest, and joined the elector on the Danube; while Tallard at the head of another army on the Rhine supported his movements, and protected his communications with France. Prince Louis of Baden, and count Stirum, who commanded the allied forces, unable to make head against the enemy, withdrew into the lines of Stolhofen, a little below Kehl, which they had carefully fortified in order to form a base of operations for the imperial armies on the upper Rhine, and there kept Tallard at bay. The Emperor was in terrible straits. The Hungarians had risen under Ragotsky, and were preparing to attack Vienna from the east. Vendôme was pushing prince Eugene slowly before him over the Brenner pass to Innsbruck. The only