The Union and Confederates both used Balloons to spy on each other - though the Union tended to do it more.. The Union did a-lot of balloon launches in Stafford,Virginia along the Rappahannock River and used them in other parts of Stafford after the Battle Of Fredericksburg... the Union was pretty paranoid about the Rebels attacking their camps in Stafford after they lost @ Fredericksburg!! so.. they used them frequently to make sure the Rebels weren't coming and the Confederates used them also, but less frequently.
This photo might be of Kelly's Ford a crossing that the Cavalry used a-lot (Battle of Kelly's Ford was a Cavalry battle) to get from Stafford,Virginia where they were camped, to Fauquier, then over the Rappahannock River into Culpeper,Virginia. Kelly's Ford was used a-lot in 1863, but they may have used it in 1862? There were quite a few crossing points a-long the Rappahannock to get into Spotsylvania/Fredericksburg & Culpeper. Like U.S. Ford which was used in 1863 during Chancellorsville & also for Wilderness & Spostylvania battles. I am not quite sure where this crossing point is along the Rappahannock.. It is somewhere between U.S Ford and Kelly Ford (up river past Fredericksburg) which are just about 2-3 miles a-part of one another in Stafford & Fauquier Counties..