History: Four-photograph time-lapse view of Union cavalry crossing a pontoon bridge over the James River in Virginia during the American Civil War, 1864. Link to animated version in comments. [3000x2322]

http://i.imgur.com/JjQinlM.jpg via /r/HistoryPorn http://www.reddit.com/r/HistoryPorn/comments/4f714i/fourphotograph_timelapse_view_of_union_cavalry/