Many of the Union soldiers watching the more than 12,000 Confederates steadily advancing towards them on Cemetery Ridge at the beginning of the PPT Charge later recalled an interesting phenomenon as the Rebels got closer. The long lines of butternut clad men would disappear and then suddenly reappear as though they were coming up out of the ground. This was the result of the long lines passing through the series of deep swales that run between the two ridges. Just looking across the empty field today, the swales are hardly noticeable, however by following the line of an east-west fence line, the depth and frequency of the dips can be more easily discerned. My photograph taken from near the Virginia Monument shows a fence line running towards Cemetery Ridge that clearly demonstrates the point Much of the area between the two ridges inexplicably was turned into Camp Colt, a training base for a tank corps in 1918. Despite the damage undoubtedly done to the terrain, the swales remain, basically unchanged.