original_query: What were the two German cloud gas attacks on British troops near the village of Hulluch in 1916?
query: What were the two German cloud gas attacks on British troops near the village of Hulluch in 1916?
answer: The first attack, on April 27th, involved a chlorine and phosgene gas release followed by raiding parties. The second attack, on April 29th, also used gas, but unfavorable winds blew it back on German troops, causing significant casualties.