He soon began experimenting with chlorine gas to be used in trench warfare. Conflicted Jason Kelce Reveals Who He'll Root for in Eagles-Chiefs Super Bowl 12 Strange Places In The United States So ...

In the lead-up to World War II there ... poisonous gas, so by 1938 the government had issued respirators to every man, woman and child in the nation. More than 40 million gas masks were issued.