Across
- 4. Flattened enemy fortifications. Helped break the stalemate of trench warfare
- 7. military observation of a region to locate an enemy or their strategic features
- 8. long ditch dug in the ground
- 9. Difficult to detect. New ability to fire on ships without warning
- 10. Lungs filled with fluid
Down
- 1. metal cable with sharp spikes (barbs), used for trench defense
- 2. area between 2 opposing trenches
- 3. Created chemical burns on contact, blisters oozing yellow fluid, blindness
- 5. 1st widespread use of rapid fire, spewed 400-500 rounds/minute
- 6. aerial battles