compare and contrast the sense of battle within this chapter to that found in chapter 16 why is there a difference here

There is a greater sense of aggressiveness, fight and purpose in chapter 19 than in chapter 16. Check out this quote:

"The friend of the youth aroused. Lurching suddenly forward and dropping to his knees, he fired an angry shot at the persistent woods. This action awakened the men. They huddled no more like sheep. They seemed suddenly to bethink themselves of their weapons, and at once commenced firing. Belabored by their officers, they began to move forward. The regiment, involved like a cart involved in mud and muddle, started unevenly with many jolts and jerks. The men stopped now every few paces to fire and load, and in this manner moved slowly on from trees to trees." (Chapter 19)