 They had little in the way of siege artillery and engineers and the Dutch supplied them to the Prussians.The advance of the Dutch siege lines was too fast for the Prussians and the heavy resistance of the garrison, the need to coordinate the advances, bad weather and the arrival of French troops under Camille d'Hostun, duc de Tallard on west bank of the Rhine forced the Dutch to repeatedly postpone the storming of the fortress throughout May.The trenches were opened on 18 April and the Dutch intended to take the counterscarp after one week, but the storm was launched only on 9 June.