The top photo shows a battle site strewn with casualties and the dead. We'll assume the surgeon who had the kit below would be a field surgeon, doing what he could for the men as soon as he can reach them.
Antiseptic surgery was largely pioneered by Joseph Lister in the 1860s. We don't know how many Civil War surgeons and doctors practiced it.
It has been estimated that 120,012 men were killed in action during the American Civil War. A further 64,582 died of their wounds. However, the greatest danger facing soldiers during the war was not bullets but disease. For example, 5,177 soldiers in the Union Army died of measles during the war.
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