Here, unfortunately, he came to the conclusion that since he had encountered such difficulties in crossing the flat country he should meet with even greater obstacles and delays in ascending the hill in the dark; he therefore took the fatal resolution of remaining where he was until daylight, and accordingly ordered the column to halt. Had he continued his march he would have reached the summit of the Weinberg unopposed, and the fate of the battle on the following day would have been changed. But the Imperialist leaders, Gallas and Cardinal Infanta Don Fernando, had not been unmindful of the commanding position of the hill upon which Horn was marching, and had given orders that it should be occupied before daylight by four hundred Spaniards.

The commander of this force was as over prompt in the execution of his orders as Horn was over cautious. He reached the top of the Weinberg before midnight, and at once set his men to work to intrench themselves strongly. As soon as daybreak enabled Horn to see the fatal consequences which had arisen from his delay he ordered his men to advance. With their usual gallantry the Swedes mounted the hill and rushed at the intrenchment. It was defended with the greatest obstinacy and courage by the Spaniards; but after desperate fighting the Swedes forced their way into the work at two points, and were upon the point of capturing the position when an ammunition wagon accidentally exploded in their midst, killing great numbers and throwing the rest into a temporary disorder, which enabled the Spaniards to drive them out and again occupy the intrenchments.