Breastworks are earthen or rock fortifications to protect soldiers factories that manufactured military armaments protective shields for men operating gatling guns armor plating that protects soldiers during battle

Breastworks are temporary fortifications, very often earthworks, which serve to defend soldiers. They are made to be up to the height of their breasts, so that the soldiers are protected in the standing position while shooting at the enemy. In addition to this temporary, there is also a more permanent stone structure, which resembles a masonry or parapet.

The answer is earthen or rock fortifications to protect soldiers.

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