This picture was taken in 1863 and shows a group of Black Men working on railroad tracks. If you look at the tracks, they are bent. This would indicate that the track had been sabotaged by Confederate Soldiers, who loved to pull up rails, and then bend them. This made much more of a mess, as the old rails could not simply be relaid, new ones had to be found and brought in. Later in the war, the North figured out ways to straighten the bent rails to speed up the repair process. I thought this was an unusual Civil War image.