I attended the lecture at Pea Ridge and it was excellent. He talked about the methods they used and compared battlefield archeaology to a crime scene investigation. They were able to sort out the fighting in one of the fields (don't recall which, but as an example whatever field it was they thought the fighting had been north-south but the archeaological record is showing that the fighting was east west). He showed a map showing artifact recovery and you could see the lines of battle in the field. He showed a picture of a fired minie ball and said they now have a formula that they can use on the bullet and determine how fast it was traveling at impact and knowing muzzle velocities they can pretty much tell you were the soldier was standing that fired it. He talked about finding bar canister which was unexpected and about doing some sort of microscopic analysis on shells and fragments known to be fired by each side to see if they could tell a difference in the quality of the manufacture of the iron and it was exactly the same. They could also tell that the projectiles they looked at had been made during the winter due to the rate of cooling. Just lots of cool stuff.