Hardtack, a dry flour biscuit, earned nicknames such as "tooth-dullers," "worm castles," and "sheet iron crackers" from soldiers. Hardtack made up a large portion of a soldier’s daily ration. Factories in the North baked hundreds of hardtack crackers every day, packed them in wooden crates and shipped them out by wagon or rail. If the hardtack was received soon after leaving the factory, it could be tasty and satisfying. Usually, the hardtack did not get to the soldiers until months after it had been made. By that time, they were too hard to be eaten without first being soaked in water or coffee. Sometimes they were infested with small bugs the soldiers called weevils.
Hardtack could be eaten plain though most men preferred to toast them over a fire, crumble them into soups, or crumble and fry them with their pork and bacon fat in a dish called skillygalee.
The soldiers' rations of hardtack. 2011. Photograph. National Parks Service.https://www.nps.gov/media/photo/gallery-item.htm?id=2F4A5AE3-1DD8-B71C-07F4B90CDE67F47F&gid=2F1E048C-1DD8-B71C-07DE0FCDFFC7AEB0
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