Gustavus did not let the grass grow under his feet. He set out at once for Saxony with the elector of Brandenburg, effected a junction with the Saxon army, and marching towards Leipsig met the army of Tilly drawn up in battle array on the field of Breitenfeld on September 17th, 1631. Tilly marshalled his men to the number of 32,000 in one long line of battle along rising ground overlooking the little stream of the Loderbach. In the centre were posted as usual the solid squares of pikemen flanked by musketeers, which formed the main battle according to the tactics of the Spanish school. On the right wing was Furstenberg with the horse of the Italian army, while the left was guarded by the fiery Pappenheim and his famous cavalry. Between the wings and the centre were placed the heavy guns, probably between thirty and forty in number. Tilly himself on his well-known white horse put himself among his Walloon fellow-countrymen in the centre. The arrangement adopted by Gustavus was somewhat different. The army was drawn up in two lines, with a reserve of cavalry behind each line, and a final reserve also of cavalry behind the centre of the whole army. The extreme left opposed to Furstenberg was occupied by the Saxon troops under the elector in person. On the right of the Saxons, and in touch with the Swedish centre, was Horn with the Swedish cavalry. Gustavus himself took command of the right wing, opposed to Pappenheim, with the rest of the cavalry; but between each division of cavalry on both wings in the first line was a detachment of two hundred musketeers. The infantry occupied the centre, marshalled in very much smaller squares than those of Tilly, and having a much greater proportion of musketeers to pikemen, while in front of each regiment was the light or field artillery. The heavier guns, in all about one hundred, under the command of Torstenson, were placed in the left centre. In numbers Gustavus was decidedly superior. His own army amounted to some 26,000 men while the Saxons could not be less than 15,000. His guns, too, though not so heavy as those of Tilly, were far more numerous, and could fire three shots to one of the imperialists. The wind and the ground favoured Tilly. The battle began with an artillery duel in which the quick-firing Swedish pieces wrought fearful havoc among the dense masses of the imperialist army. Yet the stubborn old marshal remained immovable amid the hail of the balls. Pappenheim, younger and less disciplined, lost patience. Without orders he suddenly launched his cavalry on the Swedish right, but Gustavus was ready for him. The musketeers received him with a volley which made him reel, and Baner at the head of the reserve cavalry, and Gustavus himself with the right wing, dashed upon him at the moment and drove him fairly off the field. Meanwhile on the extreme imperialist right Furstenberg in his turn threw himself upon the Saxons, drove back their cavalry first on