July 21st 
Made breastworks of logs, and by nine Oclock A.M. the Yanks artillery opened on us from our left, their shell enfalading our lines. They have heard us chopping down trees and building our works and have our range – and the woods are so thick we can’t see them. Their artillery are killing our men very fast – One company just to my left after finishing their works sat down to rest in a little ditch they had dug, when a shell came and took them at one end and killed and crippled every man in the ditch….
My Company had completed their works when as I was lying down resting on my elbow – and another man in about the same position with our heads about two feet apart and our feet in opposite directions, a shell (schrapnell) exploded just between us – blowing me one way and him the other hurting neither one of us but killing three men about 10 ft. from us eating their breakfast.
About the middle of the day the small arms open on us in front of us and as soon as our pickets came in a general fire opens along our line.
There are some dismounted cavalry to our right making our line longer and when the Yanks make the charge the cavalry shoot their guns off as fast as possible, while our pickets are getting in front of them. The pickets could do nothing but lie down and be captured by the Yanks – I lost three thus. As soon as the cavalry discharge their guns they all break and run like good fellow which leaves our right exposed and the Yanks following the cavalry pass by the right end of our line while those in front of us are held back by us.
Our Regt. which is on the right are taken out of the works and form a line at a double quick behind our works and perpendicular to it, which puts the left of the regt at the works – while the fight is the length of the regt. off – We got forward quick time and drive the Yanks out in short order, and swing around and occupy our line again – then we are put in single file so as to cover the ground that had been occupied by the cavalry….
I am put in charge of the Picket line today to bring off the Pickets tonight – Our whole corps (Hardees) will move tonight some where, and the Yanks are so close to us in front that is a dangerous maneuver – requires considerable skill.
Samuel T. Foster, Diary, July 21, 1864 – excerpts and spelling is original
(Source: The Civil War: The Final Year Told by Those Who Lived It; Brooks D. Simpson, Editor, 2013, pages 273-274)
We read about them all the time in military history, so what are pickets? Pickets are the guards for a larger force or for a position. These soldiers posted in a scattered line, usually quite a distance in advance. A picket guard – according to some period sources – was supposed to be formed with forty privates accompanied by four corporals, two sergeants, and a lieutenant.
Now, a picket line is technically differently than a skirmish line, but there are similarities. Specifically, a skirmish line is formed with a body of troops (usually a company in a regimental scenario or regiment for a brigade or division) separated at specified intervals to cover a battle position. A skirmish line is intended to fight, a picket line typically just guards and exchanges occasional shots. Foster recorded in his journal about the pickets from his company who were in front of the lines and often in trouble as Union troops probed or moved against the position.
By mid-July, the Confederate army had fallen back to the defensive lines around Atlanta.
On July 20, 1864, the Battle of Peachtree Creek resulted in another Union victory. The Confederates got a new commander; John B. Hood replaced Joseph E. Johnston.
Hood decided to withdraw part of his army, hoping to draw Sherman into a trap. Meanwhile, he sent Confederate General Hardee’s corps on a march of fifteen miles toward the Union left flank and rear. Ultimately, the planned attacks and maneuvers did not succeed and the Battle of Atlanta ended in another Union victory and with high casualties for Hood’s newest army.
“Woods so thick we can’t see them.” A few weeks ago, I was chatting with some friends about eastern battlefields. One of the friends wondered why the soldiers couldn’t see each other during a particular maneuver. So we had a discussion about natural landscape.
If you live on the east coast or in the south, you’re probably rolling your eyes that this needed discussion, but hang on! California hills and forests are way different. This seems like an easy fact, but we often picture scenes in the forests we know unless the actually land is explained. So if I was talking about the mountain forests of California, you might picture the woods of Tennessee until I explained that I meant redwoods! See the challenge.
This is why “boots on the ground” research is so important and delving into topography/landscape changes in the last decades to understand Civil War battles. If you can’t make the trek to the site, the next best things? Google Maps on satellite view and on site photographs give a better idea of a battle area and why they couldn’t just see the enemy.