History: Second Battalion of the IX Coast Artillery Corps demonstrating the hollow square formation used in the event of a street riot. New York City, 1918. [1738x1404]

https://i.redd.it/3szh4vt4t7l11.png via /r/HistoryPorn https://www.reddit.com/r/HistoryPorn/comments/9ecyqy/second_battalion_of_the_ix_coast_artillery_corps/?utm_source=ifttt