The April 6, 1862 Battle of Shiloh resulted in 16,000 wounded, and 3,000 dead. As dusk fell, some of the wounded appeared to glow in a mysterious light. These soldiers were later observed to heal more quickly than those that did not. As a result, the protective light was nicknamed "Angel's Glow."
Mr. Martin and Mr. Curtis were able to provide an explanation, with the help of Mr. Martin's mother, a specialist in luminescent bacteria as a microbiologist for the USDA Agricultural Research Service.
LINK: Soniak, Matt (2012), "Why Some Civil War Soldiers Glowed in the Dark," mental_floss, April 5